175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 75 doi:10.2533/chimia.2008.75 CHIMIA 2008, 62, No. 3

Chimia 62 (2008) 75–102 © Schweizerische Chemische Gesellschaft ISSN 0009–4293

150 Years of Chemistry at the University of Zurich#

Conrad Hans Eugster*

Abstract: This article was published in Chimia 1983, 37, to commemorate the 150-year anniversary of Chemistry at the University of Zurich. This excellent historical account displays a depth of information and research that makes it very worthwhile reproducing here. It presents an account of Chemistry at the University of Zurich up to 1983 and has not been changed or updated in any way except translation into English from the original German. Keywords: Chemical Institutes UZH · Karrer, P. · Werner, A.

1. Introduction Laws passed in 28th September 1832, creat- cist, but had been awarded his doctorate in ed and promoted by liberal political forces, chemistry in 1825 with Gmelin in Heidel- Medicine and the sciences were important long years of planning for the establishment berg. He subsequently assisted Mitscherlich subjects in the town of Zurich long before of a University finally came to fruition. On in Berlin and then completed his habilita- the University was founded. Names like 29th April 1833 the University was cer- tion at the University of Heidelberg in 1830 Konrad Gessner, Josias Simmler, Johan- emoniously inaugurated with 159 matricu- with his work on bromine which gained nes von Muralt, Johann Jakob Scheuchzer, lated students. The first vice-chancellor was wide attention.[2] In Zurich he quickly at- Johannes Gessner or Salomon Schinz were Lorenz Oken, Professor for ‘General Natu- tracted many students. It was reported that known far beyond the confines of the town. ral History, Natural Philosophy and Human he lectured very clearly, freely and almost The ‘Naturforschende Gesellschaft Zürich’ Physiology’. With this choice, the Erzie- elegantly. [3] His experiments succeeded ex- (Zurich Society for the Natural Sciences), hungsrat (Cantonal Education Authority) cellently. Löwig’s also lectured on pharma- founded in 1746, also had a significant in- placed a stronger emphasis on the sciences ceutical chemistry and acted as an auditor fluence in disseminating scientific concepts than was apparent at the (much older) Uni- in this subject for the Zurich apothecaries. and reasoning. With the new Education versity of Basel or − one year later − the He soon became more widely known in sci- University of Bern. This was particularly entific circles as a successful author of text- obvious in the weighting that chemistry re- books.[4] Löwig obliging nature made him ceived in the new curriculum from the very many friends, especially in the secondary beginning: a Chair specifically for chemis- schools and amongst his colleagues in the try was created whereas the teaching of as- Faculty of Medicine. His research initially tronomy, botany, mathematics, mechanics, concerned analysis of local mineral waters, mineralogy, physics, zoology and geogra- presumably due to the available instrumen- phy (in the second semester) was done by tation and his own scientific background.[6] senior lecturers (Privatdozenten). The new However he soon turned to organic and chemistry professor was also provided with physiological problems after acquiring new a laboratory in the ‘Carolinum’ (Fig. 1)[1] improved laboratory equipment and certain- and a small annual budget for equipment, ly at the suggestion of colleagues at the Fac- and after a short time he was even given a laboratory technician. It was fortunate the first occupant of the Chair in Chemistry was a chemist who not only taught but also un- dertook experimental research which ena- bled a flourishing school to develop.

* Correspondence: Prof. C. H. Eugster Institute of Organic Chemistry 2. Early Times and the First University of Zurich Highlights: The Carolinum and Winterthurerstr. 190 CH-8057 Zurich Rämistrasse 59; Professors Löwig, Schweizer, Städeler and Wislicenus # Translated by Dr. G. Harvey CHIMIA Technische Redaktion The first occupant of the Chair in Chem- Pestalozzistr. 34 CH-8032 Zurich istry was Carl Jacob Löwig (Fig.2), who was Fig. 1. The ‘Carolinum’ (Zwingliplatz to the front, E-mail: [email protected] 30 at the time. He was originally a pharma- back left Kirchgasse, back right Grossmünster) 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 76 CHIMIA 2008, 62, No. 3

Fig. 2. Carl Jacob Löwig Fig. 4. Laboratory at Rämistrasse 59 (no. 1 C. J. Löwig, no. 2 M. E. Schweizer, no. 8, H. H. Landolt, no. 13 C. Heusser, from ref. [28] ulty of Medicine (principally Schönlein and try with certain improvements until 1887. tion had hoped to attract Adolf Strecker, a Kölliker). His discovery that cellulose made Matthias Eduard Schweizer moved into the talented student of Liebig’s, to Zurich but up the outer sheath of tunicates attrached ‘Kantonsschule’ with Löwig. Previously this was unsuccessful. wide interest. Until that time cellulose was in Germany he had trained in chemical The authorities were very farsighted considered as a typical plant material. More technology and in metallurgy and mining. in their appointment of Städeler: in teach- extensive investigations were devoted to the Where and when he completed his disserta- ing he showed great merit in introducing a synthesis of aliphatic mercaptanes and sul- tion is not known. Schweizer was initially systematic curriculum with written instruc- fonic acids, mustard oils and novel reactions a lecturer at the Industrial School but com- tions for practical sessions[9] and by produc- of antimony, lead and tin with alkylhaloge- pleted his habilitation in chemistry and met- tive research in organic chemistry. Subjects nides. The latter reactions can be considered allurgy in 1841. In 1852 the ‘Regierungsrat’ included amino acids, allantoin, creatine, as highly significant from a historical view- (the Cantonal government) promoted him chitin, fibroin, dyes from egg yolk etc. point since, as we now know, Löwig was to associate professor. Schweizer’s most Städeler determined the correct empirical able to synthesize for the first time triethyl significant achievement was the discovery formula of lactose, xanthine, scyllitol etc. stibane, tetraethyl lead (!) and alkyl stannane that cellulose could be dissolved in tetram- and synthesized pinacones from ketones by and to characterize these as organometallic mine copper solution (1857). The so-called means of reduction with metal/acid. compounds. Löwig’s method, the reaction Schweizer’s reagent formed the basis much When the ‘Eidgenössische Polytech- of Na/Pb- and K/Sb-alloys with ethyl iodide later for the industrial production of fibres nische Schule’ (Federal Polytechnical etc. is in principle still used today for the in- from precipitated cellulose (cuprammo- School)[10] opened on October 15, 1855, dustrial synthesis of tetraethyl lead. nium silk or Kupferseide). Städeler was named Professor of Theoreti- Löwig’s success at teaching resulting in Löwig left Zurich in 1853 to take up a cal Chemistry but also retained the title of an increased number of students and soon professorship at the University of Breslau Professor at the University. [11] He initially made increases to the available space nec- as the successor to Robert Bunsen. He not carried on using the laboratories in the essary. New laboratories were occupied in only left a painful vacancy behind in Zu- ‘Kantonsschule’. He moved into the chem- the ‘Neue Kantonsschule’[7] (Fig. 3, Fig. 4) rich, even more significant was that he took istry building at Rämistrasse 45 (later 85) that had been built according to Löwig’s his talented student Hans Heinrich Landolt [12] in 1861, which had been built according design. At the time they were considered with him. Landolt is recognized today as the Städeler’s and Bolley’s plans.[13] exemplary. They were used by Chemis- founder of physical chemistry in Germany. The position of associate professor left His name lives on in the unique collection vacant by death of Schweizer in 1860 re- ‘Landolt-Börnstein’. Löwig’s new appoint- mained unfilled for some time until the ar- ment confirmed the reputation that he had rival of Johannes Wislicenus in 1864, who at that time. Despite this one cannot nowa- was only 29 at the time. This appointment days count him as one of the great chemists allowed the University to take on a first- of his time. Löwig tolerated the limitations class organic chemist. In his 12-year career in Zurich and made the best out of them for as a chemist, Wislicenus had made a signifi- himself and the University. He created the cant contribution to Kekülé’s new and at the foundations for a successful development time revolutionary structure theory. [14] of the School of Chemistry. [3,8] After an eventful and difficult youth, The successor to Löwig was Georg Wislicenus completed his dissertation in Städeler, a Wöhler student from Hannover. 1860 under the supervision of Städeler. In He had been working as an associate pro- the same year he made his habilitation in fessor in Göttingen since 1851. In winter ‘pure, applied and physical’ chemistry at the Fig. 3. Rämistrasse 59 (photo taken from the semester 1853/54 he took up his position University and the Polytechnic.[15] After his direction of Heimplatz) in Zurich. Originally the Erziehungsdirek- appointment to associate professor and head 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 77 CHIMIA 2008, 62, No. 3 of the chemistry laboratory at the ‘Kantons- schule’ (also known as University Laborato- ry II) Wislicenus began to lecture alternately on inorganic and organic chemistry.After his promotion (1867) the University had for a short time two full professors for chemistry although Städeler only lectured at the Poly- technic and announced his courses in the university course book. Under the leader- ship of Wislicenus the University Laborato- Fig. 5. Rämistrasse 45 ry II developed to extraordinary levels, with (later 85; photo experiments that no longer concentrated on taken from physiological-chemical problems but rather Schmelzbergstrasse) the new structural chemistry. Despite the modest demands lack of space became ever more problematic. At the same time the left Zurich and took up a position at the were the energy carriers rather than pro- activities of Städeler’s group at the Poly- University of Würzburg.[16] teins, received wide-spread recognition. technic slowed, caused in part by Städeler’s Many of the scientific achievements In Zurich Wislicenus founded the ‘Che- increasing chest and heart problems. that Wislicenus produced in Zurich are to- mische Harmonika’, a scientific associa- New rooms were found when the Labo- day textbook knowledge, for example his tion for the discussion of new discoveries ratory for Veterinary Medicine and the ‘Kan- work on the composition and synthesis of in chemistry. This was the immediate tonsschule’ moved into the chemistry build- lactic acid and homologues and his mo- predecessor to the ‘Zürcher Chemische ing at Rämistrasse 45 (Fig. 5). Wislicenus mentous interpretation of the isomerization Gesellschaft’ (Zurich Chemical Society) declined the honour of a professorship at the phenomenon of lactic acid of a ‘different which was founded in 1870. University of Basel. His students celebrated distribution of atoms in space’. Wislicenus’ After Wislicenus’ departure, the agree- his decision with a torchlight procession. interpretation was the forerunner of the tet- ment between the University and the Poly- When Städeler retired in 1870, Wislicenus rahedron theory of Van’t Hoff and Le Bel. technic regarding a shared Chair in chemis- became his successor. His investigations on the ‘origin of muscle try was discontinued. The chemistry lectur- He left the Kantonsschule and moved to force’ that he undertook in collaboration ers had already left the laboratory on the the Rämistrasse. In 1871 the Bundesrat (the with the physiologist A. Fick and the ther- Rämistrasse in 1870 and used the largely Swiss government) appointed him Director modynamic chemist R. Clausius in which antiquated laboratories in the Kantons- of the Polytechnic. Only one year later he they were able to show that sugar and fats schule until 1887. The long-term interde-

7DEOH  )XOO DQG DVVRFLDWH SURIHVVRUV RI FKHPLVWU\ IURP /|ZLJWR.DUUHU VKDUHG Table 2. The buildings occupied by Chemistry at the University SURIHVVRUVKLS Carolinum (today Kirchgasse9) 3URIHVVRU )XOO 3URIHVVRU $VVRFLDWH 1833 3RO\WHFKQLF 8QLYHUVLW\ 3URIHVVRU 8QLYHUVLW\ Löwig /|ZLJ 1842   Neue (Rämistrasse 59) /|ZLJ Kantonsschule Löwig    Städeler 1861 Altes Univ. Lab. I 6WlGHOHU 6FKZHL]HU Chemiegebäude (formally Rämistrasse   ‚ 85,demolished in    1912) 6WlGHOHU Schweizer 1861    Univ.Lab. II Wislicenus Uni+Poly+other labs :LVOLFHQXV Merz (Städeler,sharedProf. 1855 1870)    (Wislicenus, sharedProf. :LVOLFHQXV 1870 1872)   1870 :LVOLFHQXV WeithoP lytechniconly Polytechnic   1887 1887 Universitätstrasse 6 0HU]   Merz 0HU] Abeljanz,Werner 1909   Rämistrasse76 :HLWK 1967 Schönleinstrasse 2   " $ b HOMDQ] 1978    WKHQ Winterthurerstrasse 190 IXOO SURI :HUQHU   VXFFHVVRUWR0HU] :HUQHU   .DUUHU  .DUUHU   175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 78 CHIMIA 2008, 62, No. 3 pendence of chemistry between the Univer- ing with Städeler after a disagreement and from his teaching position. Merz and Weith sity and the Polytechnic had brought many joined the group of Wislicenus at the Uni- published many of their results together. disadvantages for the University. [6] The versity Laboratory II. During this time he The publications are characteristic of the complicated personal and accommodation got to know Weith, with whom he enjoyed a time in which the main emphasis was on the relationships are shown in Tables 1 and 2. friendly and productive collaboration until discovery of new reactions, i.e. the transfor- Weith’s death. mation of functional groups. In Zurich the Weith, born in 1846 in Homburg (Prus- main interest was aromatic chemistry. As a 3. The Team of Viktor Merz and sia), also studied chemistry at the Polytech- reminder: in 1858 Peter Griess discovered Wilhelm Weith nic but then went to Bunsen in Heidelberg. the aryl diazonium salts, in 1865 Kekülé In 1865 he completed his dissertation at the presented the formula of benzene and in The names of these two chemists are no University of Zurich. Merz and Weith com- 1866 Erlenmeyer that of naphthalene. In longer familiar to today’s chemists; they are pleted their habilitations at almost the same 1868 Caro and Graebe and Liebermann si- not commemorated by any ‘named’reaction time at both the Polytechnic and the Uni- multaneously synthesized alizarin. nor are they associated with any significant versity. Their research was carried out at the Analysis of the publications of Merz discovery. There are various and partly rath- University however. Merz was appointed as yields a strange picture: 18 were written er odd reasons for this that bear explana- associate professor in 1869 and full profes- alone, 68 with Weith and other colleagues, tion. The reason that Merz and Weith merit sor and successor to Wislicenus in 1871. whereas about 100 were written by him but a Section of their own here is partly due to At the same time Weith was appointed as- published solely under the name of the re- the fact that they were able to attract a large sociate professor. During the appointment spective student! It is for this reason that a number of students for chemistry and gave procedure to select Wislicenus’ successor, large number of significant discoveries are chemistry as a subject considerable weight- the retention of the shared professorship not associated with the name of Merz (or ing during a difficult time so that it was able at the University and Polytechnic was ex- Weith).[21] to persist despite the glittering activities of amined closely by the University Commis- Many syntheses were concerned with Viktor Meyer, Wislicenus’ successor at the sion and at the same time the qualities of mustard oils and their derivatives in com- Polytechnic. This was also despite the much the two candidates were compared: Merz’ petition with the much more well-known more primitive working conditions that had teaching style was less vigorous whereas A. W. Hofmann. Werz and Weith succeeded to be endured compared to their colleagues Weith spoke more fluently and eloquently in 1879 with the first synthesis and at the at the purpose-built and well-equipped lab- although without the scientific thorough- same time the correct structure determi- oratories of the Polytechnic. ness of his colleague. The two men com- nation of diarylcarbodiimide ( 1 ) and they Viktor Merz[18] (Fig. 6) was born in plemented each other excellently both in investigated many addition reactions of 1 1839 in Odessa, Russia, to Swiss parents character and scientifically. [19] with alcohols and amines. The isatine and originally from Appenzell. When he was 13 This assessment was certainly shared by indigo syntheses performed much later byT. he was sent to Zurich to attend school. He their contemporaries: Merz was described Sandmeyer (1899) relied on their research. is reported as saying that his teacher, Prof. as tenacious, persevering and purposeful The synthesis of isonitrile ( 2 ) from mustard Schweizer, inspired his interest in chem- with a large capacity for work but also shy oil followed by rearrangement into nitrile is istry. He began his studies in chemistry and taciturn whereas Weith was perceived a good example of the widely studied ‘de- at the Polytechnic with Städeler, but then as a lively, extravert blond northerner with sulfurization’ reaction (Scheme 1). For the transferred to the University in summer se- an engaging character that won him many first time it was possible to transform aryl- mester 1860. After studying in Munich with friends. Merz was only interested in chem- amines into aryl carboxylic acids. Liebig, he returned to Zurich to complete istry whereas Weith also showed an inter- Examination of the many publications his dissertation in 1864 with Städeler. After est in botany, geology, zoology and Swiss and lecture reports from the Zurich ‘Univer- his habilitation in 1866 he stopped work- culture. He learnt the Zurich dialect eas- sity Laboratory’ reveal a picture of empiri- ily; “He managed to find his way quickly cal sampling of the reactivity of aromatic through the unusual and for a foreigner, compounds with experimental conditions difficult to understand, political situation in that are no longer used today. For example Switzerland”.[14] syntheses of unsymmetrical arylketones The ascetic Merz often worked in the were performed by condensation of carbox- lab together with the physically weaker ylic acids with aromatic hydrocarbons and but stimulating and clever Weith until he P 2 O 5 in a sealed tube. Later, in 1873, Merz (Weith) was overcome with complete ex- discovered that the reaction of carboxylic haustion. After the early death of his friend, halides in the presence of metallic zinc pro- Merz became an increasingly withdrawn ceeded with high yields. The more efficient and lonely eccentric.[20] In 1893 he retired catalyst, aluminium chloride, was not intro-

Scheme 1. Desulfurization Fig. 6. Viktor Merz reactions 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 79 CHIMIA 2008, 62, No. 3 duced until 1877 by Friedel and Crafts and R. Bindschedler, founder of a chemical fac- organic Chemistry’, ‘Comparative Organic therefore this textbook reaction carries their tory in Basel (predecessor to Ciba) and A. Chemistry’ and ‘Stereochemistry’. It is names and not Merz’. Extensive substitu- Bischler (later a director of Ciba). obvious that Werner had an encyclopaedic tion reactions were carried out on the read- In 1886 the Polytechnic chemists moved knowledge of chemistry even during these ily accessible sulfonic acids and halides to into their impressive new chemistry build- early years. At the same time he gained the introduce other functional groups leading to ing on Universitätsstrasse 6, which in an ex- reputation of an excellent lecturer with great the discovery that perhalogenated aromat- tended form is still in use today. Its excellent charisma. The election to associate profes- ics easily underwent nucleophilic substitu- practical design was achieved thanks to the sor was not without controversy. [27] tion of the hydroxyl group by phenols ( e.g. planning of Georg Lunge and Victor Meyer. After the matter was settled in favour of 3 (Scheme 2)) and that in the naphthalene At the time the chemistry building on Rämis- Werner, he took over the Section A (chem- series amines occupy the position adjacent trasse 45 (and 85) became free. Instead of ists) whereas Abeljanz took over Section B to the leaving group ( 4 Š 5 ). a new construction the authorities made do (medicalstudents,teachingcandidates,food with a meagre renovation of the completely chemists). At first Werner was only permit- outdated building and moved in not only ted to lecture on basic organic chemistry. [30] the Chemical Institute but also the Hygiene His lecture course was well constructed Laboratory, the Laboratory of the Cantonal and he lectured with great conviction. The Chemist, Pharmacology and the Kantons- students rush to hear him! The 130-seat schule(!). The institutes took up residence in lecture theatre soon had to accommodate 1887. The successor of Weith in 1884 was H. 200 to 250 students. “The students sat on Abeljanz who originated from Armenia. He the window sills and aisles, and crowded had completed his dissertation under the su- around the laboratory bench”.[28] Only af- pervision of Wislicenus in 1872, was the first ter intervention by the Faculty and a decree Cantonal Chemist of the Canton of Zurich by the authorities was Werner permitted to from 1877− 1884 and produced much good take over the inorganic chemistry lecture work while in this office.[23] course in 1902.[31] Scheme 2. Nucleophilic substitution of For a long time Werner was in doubt aromatics whether to join the great enthusiasm for 4. The Werner Era organic structural chemistry or whether he This last reaction, which could not be in- should turn his attention to the neglected terpreted at the time, was also not published After the retirement of Merz in 1893, the confusing diversity that defined inorganic by Merz but by his assistant O. Kym. 27-year oldAlfredWerner (born 12.12.1866 chemistry. In fact in addition to his inves- Diarylethers were synthesized for the Mulhouse, died 15.11.1919 Zurich) was tigations on the stereochemistry of oxi- first time from phenols; also the first syn- named as his successor, initially as associ- mes and hydrazone (see below) Werner thesis of triphenyl amine from aniline and ate professor (in addition to Abeljanz, who had undertaken a great deal of research bromobenzene with potassium(!). Much was elected full professor in 1890). He be- on phenanthrene and its substitution effort was put into ring halogenations with gan lecturing in winter semester 1893/94. products, the Beckmann rearrangement Cl2 /SbCl5 . This resulted in the first synthe- He was promoted to full professor two (in connection with the structure deter- sis of perchlorobiphenyl (PCB) (G. Ruoff, years later. Werner had studied chemistry mination of stereoisomeric oximes), the 1876); the widespread use of this compound at the Polytechnic since the winter semes- synthesis of hydrocarbons with Mg orga- for industrial purposes has led to serious ter 1886/87 and completed his degree under nyls and other typically organic chemis- environmental problems today. The trans- the supervision of Lunge in technical chem- try projects. For example there was his formation of phenols into arylamines with istry in 1889.[24] After working as an assist- discovery of the ‘Beckmann rearrange- the help of tetraammine zinc salts was also ant to Lunge he completed his dissertation ment type II’ which is classified today as perfected. The substitution of aromatics under the supervision of Hantzsch which the fragmentation of an oxime with the with elementary sulfur or sulfonyl chloride he submitted to the University of Zurich production of a nitrile. He resolved trans- yielded diarylsulfide. and where he also undertook his doctor- cyclohexan-1,2-dicarboxylic acid into its Weith was often ill and therefore forced ate exam.[25] Hantzsch advised him to go to enantiomers for the first time and dem- to abandon his lab work, which however Marcellin Berthelot for one semester at the onstrated that the cis-isomer could not be is not reflected in the number of publica- Collège de France in Paris.[26] resolved. Werner also regularly published tions. During a period of convalescence in Upon his return Werner made his ha- reports on new discoveries in fields such Corsica in 1881 he died of a lung haemor- bilitation at the Polytechnic in chemistry as the alkaloids, sugars, organometallics, rhage at the age of 35.[22] Merz was deeply and lectured for three semesters (summer natural dyes and terpenes. It appears that affected by the death of his friend. Despite semester 1892 − summer semester 1893) Bischler was able to convince him after this, many noteworthy results continued to on ‘Atom Theory’, ‘Selected Aspects of In- many discussions[28] that he should con- be published, usually under the names of his students. For example the first synthesis of phena- zine ( 6 ) and 5-phenyl-oxazole ( 7 ) (Scheme 3) were performed; reactions that are well known in heterocyclic chemistry but, for the above-mentioned reasons, not associ- ated with the name of Merz. After completion of their studies nearly all of the numerous doctoral students of Merz and Weith took up positions in indus- try, reflecting their empirical and experi- Scheme 3. Synthesis mental training. Well-known names include of heterocycles 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 80 CHIMIA 2008, 62, No. 3

staircases. They were only removed com- pletely in the time of H. Schmid.[38]

Werner as a Person[39]

Werner (Fig. 9) was described by his bi- ographers, particularly in his younger years, as cheerful and sociable and as someone who sought contact with similarly thinking people. From an early age he tended to put on weight. His straightforward character and his direct and blunt manner were also mentioned, which sometimes resulted in rejection in others of a different character. Fig. 7. Laboratories in the basement of To most people he appeared, especially in Rämistrasse 45 (the his middle and later years, as a powerful, catacombs) and intellectual, almost superhuman be- ing with an unbelievable work ethic. Some were afraid of him, since he despised half- centrate on inorganic chemistry. Publica- a new building for the Cantonal Technical measures and was not easily prepared to tions on organic chemistry continued to School in Winterthur, 65,000 sFr. for reno- compromise. But it is also clear from many appear occasionally up to 1900, after that vation and improvement of the former Kan- accounts that he was honoured by most as a they ceased. tonsschule building[37] and 1,400,000 sFr. research scientist and teacher. The students The conditions under which Werner’s for the construction of the new building at called him ‘der Alte’(the Boss). Werner can monumental research was performed were Rämistrasse 74 and 76 (Fig. 8). Due to de- be described as a hard worker who followed primitive (Fig. 7).Although it must be recog- lays in the construction work, the buildings his own objectives with unbelievable tenac- nised that apart from correct mixing, skilful were not accessible until summer semester ity and always put work before personal crystallisation and careful analysis,[32] there 1909. The pride of the students and profes- matters. were no exceptional experimental demands. sors was immense.[29] To commemorate the Asaresulttheworkplaceofadoctoralstudent opening, some chemistry students, whose was equipped simpler than that of a beginner names are no longer known, prepared a today in a subsidiary practical course. document extensively describing the former The large number of doctoral students working conditions.[6] and assistants meant that every corner of One peculiarity of the new building that the institute had to be utilised: “Laboratory had been designed entirely according to benches were installed in former cellars and the wishes of Werner should be mentioned: wooden containers, in rooms in which there Werner had direct access to all the rooms was insufficient daylight even on the sun- in his wing by means of connecting doors niest day, making the use of artificial light without having to use the corridor; to the unavoidable. There was no question of small lecture theatre, the private laboratory, ventilation and the heating pipes carrying the microlab, the library and a room for steam, installed at head height, contrasted doctoral students. In addition, by climbing rather unpleasantly with the cold cement small iron spiral staircases directly from floors that provided cooling.” [6] The stu- his office, he came to the practical labora- dents named these rooms the ‘catacombs’. tory below or to the preparation room of That chemistry at the University flourished the large lecture theatre on the floor above. despite such dreadful conditions is thanks Later, Karrer also made good use of these to the genius of Werner. One should recall the excellent equipment that the students at the Polytechnic were provided with and the generous capacity that the chemistry lectur- ers had access to.[33,34] After many applications to the authori- Fig. 9. Alfred Werner ties, visits by commission members and in the face of the threat that Werner really Kauffmann[29] named the following at- intended to take up an offer from another tributes in his analysis of Werner’s com- university, [36] the Regierungsrat decided to plex personality, which naturally were submit the plans for a new building to the more or less pronounced depending on the Cantonal parliament, which was accepted circumstances: high natural intelligence, on 25.6.1905 in a referendum with a very sensitive, creative, intuitive, imaginative, goodresult.Thesumof2,790,000sFr,avery ambitious, undaunted, impulsive to ag- large amount for those days, was made up gressive, egocentric. One could add: ex- from various sources: 500,000 sFr. one-off cellent three-dimensional visualisation, payment from the town of Zurich, 225,000 extraordinary memory, systematic work- sFr. book value for the land (transferred ing methods, Werner was said to be the to non-realisable assets), 600,000 sFr. for Fig. 8. Rämistrasse 76 first in the laboratory in the morning and 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 81 CHIMIA 2008, 62, No. 3 usually the last to leave at night. He and rer, his biographer, who knew Werner ex- of molecular structure. The current theories his assistants also worked on Saturdays. tremely well, remarked in his dry manner: of acidity, basicity, amphoterism and hy- Werner also spent Sunday mornings in the “His exceptional qualities were innate: in drolysis grew directly from it, and…”[50] institute unless he went hunting in Canton his work, in the fulfilment of his duties and “…in attempting to clarify the funda- Aargau with colleagues. also in his social life.” mental ideas of valence, there is no work to Werner was very attached to four sci- His ability to supervise simultaneously which I feel so much personal indebtedness entific societies; he attended the society a large number of doctoral students is well- as to this of Werner’s” (G. N. Lewis[52]). events regularly, in which he lectured him- known (Fig. 10). During his daily rounds “Werner’s work has, indeed, been of self and he served on their committees. The he was informed about every small detail. the greatest importance for the develop- venerable ‘Naturforschende Gesellschaft Many reports attest to his excellent experi- ment of chemistry. It is remarkable that a Zürich’ (for which he served in various of- mental skills: On his laboratory bench were man with only an elementary knowledge of fices between 1894 and 1910), the ‘Schwei- a microburner, microfilter, a platinum spat- mathematics and physics should have been zerische Naturforschende Gesellschaft’ ula, countless watch glasses, a porcelain able to discover the principles according (Swiss Society for Natural Sciences), the plate and many reagents. He could perform to which atoms combine, especially dur- ‘Zürcher Chemische Gesellschaft’ (Zurich ligand exchange reactions on the micro- ing a time when it had become fashionable Chemical Society) and the ‘Schweizerische scale perfectly and was able to conclude, to doubt the very existence of atoms (Wil- Chemische Gesellschaft’ (Swiss Chemical according to the colour change, the nature helm Ostwald). It was Werner’s remarkable Society) (he was a founding member and of the new complex before the analysis re- ingenuity and powers of intuition that en- its first president). His imposing figure with sults were available. abled him to deduce these principles from the ever-present cigar was a familiar sight In his early years Werner organised dis- a study of chemical phenomena alone” at the meetings. He also helped to establish cussion evenings on new issues in chem- (G. Schwarzenbach[48]). the society journal, the Helvetica Chimica istry. They appear to have been difficult In the following three areas of research Acta. The very first publication was from for the participants to follow due to the have been selected to demonstrate the high Werner himself. demanding level of understanding required regard for Werner evident in the above quo- In his early years Werner enjoyed sport. and particularly because Werner preferred tations; the pure organic chemistry research His physical strength enabled him to under- not to use the blackboard for explanations. that has been mentioned above should not take strenuous hiking and mountaineering Werner became a Swiss citizen when be underestimated. trips, he enjoyed bicycle riding, ice skat- he married (1.10.1894) Emma Wilhelmine ing and rowing. He was a member of the Giesker (14.12.1872− 15.4.1962). He loved Oxime and Hydrazone Isomerism ‘Seeclub Zürich’. Another aspect to his this country and its democratic institutions. In his dissertation in 1890, Werner tack- character was his love of games. He was In 1898 he had a house built for his family led the controversial subject of the struc- a passionate ‘Jasser’, he enjoyed bowling at Freiestrasse 111, close to the institute. ture of the isomeric oximes; see [46,53,54] and billiards. For a time he concentrated on His son Alfred (22.7.1897− 18.12.1954) and the formulations of Meyer and Auwers chess. He was a member and later honorary became a doctor. His daughter Charlotte (1888) (Scheme 4). member of the Chess Society of Zurich. He (16.4.1902− 19.1.1980) donated the gener- This comparison reveals the uncertainty also collected stamps and owned a valuable ous ‘Alfred Werner Legacy’ to the Chemi- that prevailed with respect to basic stereo- collection. cal Institutes. chemistry in the minds of the great chemists His fondness for good food and wine is of the day and shows brilliantly the impar- generally well known. With increasing age tiality and genius of Werner’s reasoning. he indulged increasingly in alcohol until Werner’s Scientific Achievements[45] Every new chemistry student is able after he eventually became addicted. Apparently two semesters to determine the number of − but only apparently − the excessive al- “Werner’s coordination theory has been possible isomers without problem. It is no cohol had no influence on his strong body. a guiding principle in inorganic chemistry surprise therefore that Hantzsch’ and Wern- The big parties that he celebrated with the and in the theory of valence since its publi- er’s formulation was not accepted unques- chemists at Christmas or during institute cation sixty years ago. Indeed, it might have tioningly[29] because the geometric reason- outings have gone down in history. Kar- been said to underline our modern concepts ing of Werner was too novel.

a)

b)

Fig. 10. Alfred Werner with doctoral students (from the left Paul Karrer, Scheme 4. a) Four benzil dioxime isomers according to the theory of V. to the right of Werner, Hedwig Kuh, Sophie Matissen, far right, Chana Meyer and K. Auwers (1888); b) The three isomers according to the theory Weizmann, sister of the fi rst President of the State of Israel) of A. Werner and A. Hantzsch (1890) 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 82 CHIMIA 2008, 62, No. 3

The Periodic System gen atom attached to the nitrogen can be the interpretation of the cis/ trans isomeri- Werner was the first to recognise that the easily exchanged helped the formulism to zation in planar quadratic Pt(II) complexes periods in the periodic table could have dif- be accepted. From his experience in organic ( 11 and 12, Scheme 7) in 1896. The cis/ ferent lengths: after two short periods with chemistry Werner must have been troubled trans violeo salts 1 3 and 14 that were so eight elements each he placed two periods by the formulism of a chain of ‘pentava- important for Werner’s theory, were not each with 18 elements. These conclusions lent nitrogen atoms’ (hydrazine was first synthesized until 1907. Finally Jörgensen were confirmed brilliantly and unexpect- prepared in 1899 by Curtius; triazine, his accepted the octahedral structure. The high- edly ten years later by the new atom model NH2 homologue, has never been isolated). point was achieved by Werner in 1911 when from Rutherford-Bohr and the Pauli Princi- Werner never worked in this field himself. his American PhD student Victor L. King ple. Further predications that Werner made But apparently he knew the relevant litera- succeeded in separating the enantiomers 2+ − about the existence of new elements have ture down to the last detail and included the of [CoClNH3 (NH2 CH2 CH2 NH2 ) 2 ] .2X however turned out to be incorrect. known examples of isomerism into his rea- predicted by his theory with the help of soning. The possible arrangements of the diastereomeric bromocamphersulfonates The Coordination Theory six ligands around a central atom shown in (enantiomers of 15 and 16) (Scheme 8). Werner is known principally as the Scheme 6 allow in the case of [MeB2 A 4 ] The resolution was easily performed author of the coordination theory and the three isomers for 8 and 9 but only two for and the facile racemisation initially feared related valence theory. At the beginning 10. The (sparse) experimental evidence by Werner did not occur. [56] The result there was a break with tradition and a new had never produced more than two isomers stunned the world of chemistry and beyond concept for the structure of metal-ammine for [MeA2 B 4 ]. Since only one isomer was and made Werner world-famous. This reac- complexes. It was extended later by experi- known for [MeAB5 ], a symmetrical ar- tion may seem extreme from our point of ments that confirmed the theory and held rangement must be present ( 8 or 9 or 10). view today since the resolution in principle Werner’s attention for the rest of his life. The elegant formalisms of Werner[55] only proved the octahedral arrangement of It was here that he showed himself to be were vehemently rejected by Jörgensen, ligands around a Co(II) atom. But the reac- a tenacious and single-minded scientist, an the recognised expert of the time. As a con- tion to this result revealed much more than industrious and systematic collector so that sequence Werner was forced to synthesise was obvious at first sight. Many chemists at the end a new scientific field of incredible time and time again examples of suitable still clung to the semi-mystical belief that order and systematic had been created. complexes to prove his theory. ‘optical activity’ could only be associ- If we compare the generally accepted A series of complexes with complex ated with ‘life’ and ‘asymmetric carbon’ formulism of metalammines at the time charges ranging from 3 + , 2 + , 1 + , 0, 1 − , although optically active quartz and other from S. M. Jörgensen with that of Werner, 2 − , 3 − , synthesised with Arturo Miolati minerals had been known for a long time. the break with the unitarian valence scheme attracted much attention. The complexes Werner dismissed any final doubts when he going back to Kekülé becomes obvious were prepared by stepwise replacement of succeeded in 1914 in resolving the tetranu- (Scheme 5). neutral ligands with charged ligands and clear cobalt complex 17 (Scheme 9) into its The use of a ‘trivalent cobalt atom’and a the charge was determined by conductiv- enantiomers. ‘pentavalent nitrogen atom’ and the not un- ity measurements. Jörgensen countered The number of complexes of Co, Cr, Fe, reasonable assumption that only the halo- with new formulations. He also rejected Rh and Ir that Werner and his coworkers

Scheme 6. Planar, prismatic and octahedral

formulation of type MeA6

Scheme 7. Planar Pt(II) complexes, cis/ trans Co(III) complexes

Scheme 5. Formulation of metal ammine complexes Scheme 8. Enantiomeric cobalt complexes 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 83 CHIMIA 2008, 62, No. 3

by G. B. Kauffmann[29] was also published strength for a comprehensive and signifi- on Werner’s 100th birthday. cant idea.

The Tragic End 5. Paul Pfeiffer and other Lecturers at the Institute of Chemistry Werner was ill long before it became obvious to others. He suffered from strong A large group of lecturers soon began headaches lasting days. Excessive work- to gather around Werner. They extended load, cigarettes, alcohol abuse and demands and supplemented the range of lecture from all sides destroyed even his strong con- courses on offer, for example:[62] Roland stitution. From 1915 onwards his physical Scholl* (summer semester 1893− winter decay was obvious even to outsiders.[59] To- semester 1895/96) later in Karlsruhe, Graz wards the end of the summer semester 1915, and Dresden; August Bischler (winter se- Werner asked for his first leave of absence mester 1893/94− summer semester 1899), from the authorities. In the winter semester whose name is known in the literature 1915/16 his lectures had to be held at times through his isoquinoline synthesis; Franz Scheme 9. The optically active carbon-free by Prof. Pfeiffer (who replaced him entirely Feist* (summer semester 1984− winter cobalt complex in summer semester 1916); and in the fol- semester 1900/01), later went to Kiel, he lowing semester by his assistant Agthe. In was responsible for the well-known rear- February 1917 Werner took another leave of rangement of a pyrone to so-called ‘Feist succeeded in resolving into their enantio- absence; in summer semester 1917 he was acid’; Karl Kippenberger* (winter semes- mers is very large. ‘Rotate and resolve’ also unable to lecture. Abeljanz took over ter 1895/96), later in Jena, Cairo, Königs- were common terms in the institute.[57] the temporary directorship of Department berg, Bonn; Walter Dilthey* (winter se- When the first X-ray structure analy- A. In the winter semester 1917/18 Werner mester 1904/05− winter semester 1907/8), ses were published in 1914 by Bragg and tried to hold his lectures again and to run his later in Cairo, Erlangen, Bonn, he was a Bragg, P. Pfeiffer and P. Niggli recognised department. It was to be his last return. His well-known dye chemist and the teacher immediately that the crystal structures cor- memory had become erratic, he often for- of Robert Wiziger, Adolf Grün (winter se- responded perfectly with Werner’s coordi- got the names of his doctoral students and mester 1907/08− summer semester 1912), nation theory. Further developments, with although he prepared his lectures sentence a lipid chemist who was the first to syn- the exception of a passing mention of the by sentence with the help of his assistant, thesise a cephalin and a lecithin; Gustav modern textile dyes with chelated Cr(III) they were often barely comprehensible.[60] Jantsch (summer semester 1911− winter se- and Co(III) central atoms and the anti-cancer In the summer semester 1918 some of the mester 1919/20) later in Karlsruhe, Bonn, platinum complexes, will not be discussed Werner’s students sent a petition to the Er- Graz; Israel Lifschitz (winter semester here. Werner’s concepts have become part ziehungsrat asking for the ‘untenable situa- 1914/15− summer semester 1921) a physi- of everyday chemical knowledge to such tion’ to be resolved.[61] Werner was sent on cal chemist and spectroscopist; Jan Vaclav an extent that some modern textbooks in leave again. For winter semester 1918/19 Dubsky (winter semester 1914/15− winter General Chemistry no longer even mention the newly elected associate professor Paul semester 1919/20) later went to Groningen, his name. Karrer took on the lecture courses and the Brno; David Reichinstein (winter semester directorship. With a letter to the Erzie- 1911/12− summer semester 1916); Oskar hungsdirektion from 6th May, 1919, Frau Baudisch (summer semester 1912− summer The Great Honours Prof. E. Werner requested that her husband semester 1916), discoverer of copperon. be released from his position. Werner’s res- The only lecturer that will be discussed On 11th December, 1913 Alfred Werner ignation became official on 15th October, at length here is Paul Pfeiffer (21.4.1875 was awarded the Nobel Prize for Chemis- 1919. He died in the Burghölzli clinic on Elberfeld − 4.3.1951 Bonn) (Fig. 11). He try as the 14th chemist and the first Swiss. 15th November 1919. completed his dissertation under the su- Werner’s Nobel lecture can be read in ref. Dissertations on Werner’s projects con- pervision of Werner in 1898 on ‘Molecu- [58]. In Zurich he was honoured by the tinued to appear until 1922 (the last was in lar Compounds of the Halogenides with authorities, colleagues and especially the 1929). They were supervised by younger Tetravalent Tin and Tin alkyls’, worked as students with an enthusiasm that demon- colleagues. It is probable that many results a post-doc with Ostwald in Leipzig in 1899 strated in a wonderful manner the pride in from the final years were never published, and with Hantzsch in Würzburg in 1900. In Werner and effusive belief in science that particularly those with spectroscopic and the winter semester 1901/02 he completed that generation had. The Swiss Chemical chiroptic measurements. his habilitation at the University of Zurich. Society held a symposium in the name of When one considers that the publica- Werner valued him as an assistant and later its most prominent member on 2nd May, tions of Werner do not contain a single as a colleague. The pair, deep in discussion 1914 in Neuchatel, the Werner medal was patent, and that his research did not make as they walked through the corridors, be- created and the Werner Prize for young sci- any claim to practical application, one came a familiar sight: entists. The long list of honours that Werner could ask why so many talented students “Es geht der Alte durch’s Labor received during his lifetime is presented in came to work with him in his early years. gefolgt von Doktor Pfeiffer ref. [29]. Werner’s 100th birthday on 3rd They would not learn any novel laboratory Es schweigen alle Gesänge bald, September, 1966 was marked in Zurich by techniques that would be of direct use in Es regt sich ries’ger Eifer” the Swiss Chemical Society with a sympo- their later careers apart from exact obser- (from the Bierzeitung[29]). sium and another from 5th− 9th September vation and careful analysis. I tend today to in St. Moritz. assume that Werner’s attraction stemmed (The Boss walks through the lab Werner was also commemorated in from the fact that everyone close to him Followed by Doctor Pfeiffer 1966 by the American Chemical Society. [51] understood that this scientist was devoted All songs quickly fade away The interesting and informative biography to pure research and that he gave all his To be replaced by great fervour) 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 84 CHIMIA 2008, 62, No. 3

6. Female Students of Chemistry

The University of Zurich had allowed individual women to study from 1840; see refs [3,35]. A fundamental decision was not made until Nadeshda Suslowa from Peters- burg applied for admission to the Medical School. The liberal ruling caused a great amount of attention and her dissertation in 1867 must be regarded as a pioneering act by the University. The first woman to study chemistry at the University and to be awarded her Dr. phil. was Lydia Sesemann from Wiborg, Finland. Her dissertation, made under the supervision of Merz and Weith, was entitled ‘Dibenzylacetic Acid and New Syntheses of Homotoluic Acid’. Geuther had discovered acetoacetic ester in 1865 and later its use in synthesis by metallation and reaction with alkylhalides became well known. Lydia Sesemann suc- cessfully transferred this technique to ethyl Fig. 12. Doctoral students ( ca. 1916): left Jeanne Fig. 11. Paul Pfeiffer Schwyzer, Lina Lang, Fritz Fröhlich (seated in the acetate. middle), Natalie Zaremba (?) In 1887 Rachel Lloyd from Philadelphia Pfeiffer’s research concentrated ini- completed her dissertation in English (!) on on Wislicenus. The founding members in- tially on complex chemistry involving tin the synthesis of ring-substituted anilines cluded Bolley and Kenngott (Polytechnic), compounds. Handling alkyl-tin compounds from homologous phenols, supervised by Merz, Weith and Wislicenus (University). led to poisoning which nearly cost him his Merz. Whether Ira Moore (1890) is a man Fifty-seven members were registered for sight. or woman cannot be ascertained from the the opening meeting on 4th July 1870. For dissertation. many years, eight to twelve meetings were Somewhat later Pfeiffer took up new From 1900 many women completed their held per year in various restaurants in the topics, e.g . the determination of cis/ trans doctorates in Werner’s group. For example town. Topics of discussion were always cur- isomerisation in stilbenes and cinnamic Edith Humphrey from London (1901); An- rent research. The desire to report appeared acids, halochromism, light reactions of o - na Dorn from Naundorf near Dresden who to be so great that it became necessary to nitrostilbenes, complexes of nitroaromat- studied the conductivity of many carboxy- introduce a rule that no new lecture should ics and alkenes (now known as charge- lic acids (1905); Dora Stern from Göttingen be started after 10 o’clock in the evening. transfer complexes). He strove to become who worked on nitrophenanthrenquinones; Transcripts were written for almost independent and to gradually move away Cornelia Geissler from Neumarkt, Gali- from the overwhelming influence of every meeting, up to 1948. From then on cia (1907); Chana Weizmann from Pinsk, they have either been lost or were no long- Werner. There do not seem to have been Russia, the sister of the first President of Is- disagreements, however, since Pfeiffer’s er recorded. Well-known names such as R. rael (1912) (Fig. 10). The first Swiss woman Gnehm, W. D. Treadwell, E. Berl, W. Kuhn, respect for his former teacher was too was Jeanne Schwyzer, born in 1891 in New F. Ebel, T. Reichstein, M. Furter, K. Bern- great. A serious estrangement occurred at York (Fig. 12). She studied at the Bryn Mawr hard, O. Gübeli, H. Schmid can be found the outbreak of the First World War how- College and then moved to Switzerland with under the transcript writers. ever: Werner was inclined towards France her parents in 1911, where she took the Eid- whereas Pfeiffer remained loyal to the genössische Maturität and started to study In 1920 the committee decided to in- German Empire. At a time when Werner medicine. Then apparently impressed by vite external speakers. On 11th May 1923 was already ill, Pfeiffer left the Institute of the lectures of Werner, she transferred to the for example, Heinrich Wieland spoke on Chemistry in the winter semester 1916/17 Philosophical Faculty II and began her studies ‘The Chemistry of Bile Acids’, on 1st May and took up a professorship at the Uni- in chemistry. Her dissertation (1919) was on 1925, Robert Emmanuel Schmidt reported versity of Rostock.[63] After the end of the optically active chelate complexes of cobalt. on ‘The Field of Anthraquinone Dyes’ and war he moved to the Technical University In 1920 Jeanne Schwyzer married the well- on 28th May 1925 Hans Fischer on ‘Blood Karlsruhe (1919) and subsequently as the known Professor of Pharmacy at the ETH, Pigments and Porphyrines’. successor to R. Anschütz at the University Robert Eder. From 1920, in addition to the Guild of Bonn in 1922, where he became Rector Many women have undertaken research houses ‘Zur Zimmerleuten’, ‘Zur Waag’, in 1931/32. He retired in 1947. It is not in chemistry at the University since then, etc. the lecture theatres of the ETH and Uni- possible to discuss here the many publi- but they were always in the minority com- versity were used for meetings. For many cations that originated from his time in pared to their male colleagues and therefore years lecture theatres at the University and Germany.[64] Looking through his book on unsurprisingly often at the centre of atten- ETH have been used alternately. molecular compounds,[65] which was very tion in the laboratory. The Zurich Chemical Society was vital popular at the time, one is amazed how as a meeting point between the colleagues strong Werner’s influence was in inspir- of the ETH and the University and as a sym- ing him to attempt to bring a similar order 7. The Zurich Chemical Society bol of the scientific activities undertaken in to the field of ‘molecular compounds’. Zurich. However its significance has been Ultimately Pfeiffer failed in his attempt The ‘Chemische Harmonika’, the pre- gradually eroded by the many activities of because he tried to unite too many uncon- decessor to the Zurich Chemical Society, the individual institutes holding their own nected aspects. has already been mentioned in the Section colloquia and invited lectures. 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 85 CHIMIA 2008, 62, No. 3

8. The Karrer Era mary school in Möriken, secondary school the ETH (where he had lectured for seven Election and New Orientation in Lenzburg and then grammar school in semesters) took over responsibility for Aarau. In 1908 he began his studies in chem- modern qualitative analysis, food science In his recollections of Prof. Werner, istry at the University of Zurich, which he went to Dr. Baragiola, Cantonal Chemist, Karrer wrote:[28] “It was the time of the First had already completed by 1911 with a dis- who lectured in the subject for six semes- World War. This had far-reaching conse- sertation entitled ‘The Valence Isomerisa- ters, and for synthetic organic chemistry quences also for the Institute of Chemistry. tion of Cobalt’.[71] After three semesters as a and terpene chemistry Karrer was able to The many foreign students, particularly the teaching assistant to Werner, he transferred persuade Dr. Leopold Ruzicka to leave the Russians and Poles, departed like a swarm to Dr. Paul Ehrlich at the Georg-Speyer ETH. Ruzicka completed his habilitation in of bees and attempted to reach their home- Haus in Frankfurt a.M. He was promoted winter semester 1920/21 and lectured for lands. Most of few Swiss chemistry stu- to head of the chemical department already nine semesters at the University. The great dents had to report for duty at their military by 1915. Prof. M. Freund, Director of the respect that Karrer had for Ruzicka and the units. The lecture theatres and the labora- Chemistry Laboratory of the University of friendly relationship that they shared in the tories emptied; there was a feeling of de- Frankfurt, was so impressed by Karrer that early years is reflected in the recommenda- pression throughout the building. This in- he invited him to submit his habilitation to tion that Karrer wrote for Ruzicka for the creased when Prof. Pfeiffer was appointed the Science Faculty. It is not known why Faculty in July 1920. to the Chair in Chemistry at the University Karrer did not take up this offer. In addition to the above-mentioned lec- of Rostock and announced that he intended When Werner retired in 1919, finding turers, Jantsch, Lifschitz (lectured on phys- to take it up. When the writer (Paul Karrer) a successor for the most important Chair ical chemistry I and II, electrochemistry, entered the Institute as associate professor of the Faculty posed a big problem. Kar- photochemistry), Dubsky and Agthe were in spring 1918, there were only five doctor- rer was put forward as a candidate but the members of the teaching staff. Several of ate students left.” proposal only received eight votes, whilst these however were frequently on leave and Paul Karrer was appointed as associate Pfeiffer and Karrer as a team received four soon left the Institute permanently. After a professor and successor to Pfeiffer on 15th votes with Pfeiffer as the direct successor short time Karrer appointed more staff, who April 1918, with the obligation to lecture to Werner. [72] In an almost unbelievable will be described below. for 6 − 8 hours a week and a basic salary of manner the minority on the Faculty sought A microanalytical laboratory for the 5,000 sFr. [66] At the same time his former further recommendations[73] and in doing so institute was installed very quickly, since ‘Lehrauftrag’, which was entitled ‘Physical directly confronted the Erziehungsdirektion Karrer was well aware of the time delay and Theoretical Chemistry’, was altered to and the majority of the Faculty who were and fluctuating reliability when the com- ‘Aromatic and Special Fields of Organic of the opinion that Karrer was more ver- pounds were analysed by the person who Chemistry’. Specifically mentioned were: satile and more scientifically capable than had synthesised them. Many of the chem- dyes, alkaloids and heterocycles, terpe- Pfeiffer. The Hochschulkommission then ists from that time will remember Dr. Ger- nes and camphor, proteins, glucosides and stated in a careful comparison of the two trud Bussmann who ran the microlab for sugar, stereochemistry. It is astonishing candidates and with remarkable clarity that many years. and unexplained why three semesters after if Pfeiffer had not left Zurich three years It is clear that the reorientation of the Pfeiffer’s departure passed before a succes- earlier he would undoubtedly have been ap- research and the systematic improvement of sor was named. Particularly because the pointed Werner’s successor. The possibility the Institute infrastructure were some of the decision to appoint Karrer was unanimous of three chemistry professorships was also most important decisions that Karrer made in both the Faculty and the University Com- considered ( i.e. including Abeljanz, who at this early stage. They formed the basis mission. would not retire until 15.4.1921). However upon which the Institute prospered. In fact The request to appoint Karrer was based there were strong reservations due to the at the time no-one had been able to break literally in part on the extensive recom- close similarity in the research fields of Kar- free of Werner’s areas of expertise. This only mendation from Werner dated 28th January rer and Pfeiffer and because such a decision 1918,[60] in which he analysed the situation would delay the introduction of new and with clarity and vision and in which he as- important areas such as physical chemistry sessed the possible candidates Adolf Grün, for many years. Finally the Hochschulkom- Ernst Berl, Paul Karrer, Adolf Kaufmann mission found out from Pfeiffer that he was and Julius Schmidlin. Werner wrote about willing to return to Zurich but only under Karrer, whom he had unhesitatingly placed the condition that he would take over the at the top of the list of candidates: “... his directorship of the institute with no restric- research demonstrates a versatility that tions whatsoever. This and the recognition indicates a fundamental treatment of the that Karrer’s clear tendency towards a phys- problems.....and shows that Dr. Karrer iological basis in organic chemistry “which works with a clear vision and particularly for a teacher with many medical students” with excellent technical skills in the diverse give him a clear advantage in this respect, areas of physiological and therapeutically led to a decision: the Hochschulkommis- significant chemical compounds....I am sion voted Karrer unanimously as “Head convinced that these qualities ensure that of the Chemical Institute”; the Cantonal Dr. Karrer will become a very successful Government confirmed the appointment on scientist....” 16th October 1919. Paul Karrer[67] was born as a citizen of From that moment Karrer (Fig. 13) ex- Teufenthal AG on 21st April 1889 in Mos- ecuted with care and utmost sensitivity the cow to Dr. Paul Karrer, a dentist, and his decisive reorientation of the Institute:[74] wife Julie (nee Lerch). In 1892 the family The Department of Physical Chemistry returned to Switzerland and lived for three was created on 15th October 1920 and Vic- years in Erlenbach on the lake of Zurich tor Henri was appointed as professor (see before settling in Wildegg. He went to pri- Section 10). Prof. W. D. Treadwell from Fig. 13. Paul Karrer 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 86 CHIMIA 2008, 62, No. 3 became possible later once the theoretical was able to find the key to the molecule This overview can only show a few of foundation of atomic structure was cre- structure of the polysaccharides. This was the highlights of Karrer’s research. They ated. From today’s point of view it can be achieved by Hermann Staudinger (ETH), result from incredibly intensive research considered good fortune that Pfeiffer, the whose fundamental new concept of the activities and active collaboration with ‘natural’ successor to Werner was not ap- covalent bonding of monomeric units to talented doctoral students and assistants, pointed. build a macromolecular chain ultimately demonstrated by the number of publica- triumphed over all other theories. tions produced: 35 articles in 1934 fol- Karrer’s Scientific Achievements Karrer and his group made great lowed by 39 the next year! Some of the During the extraordinarily long time progress in the new field of the configu- results were obtained in competition with span of 47-years academic research as a ration of proteinogenic amino acids: With other research groups. The last extensive Professor and Director, in addition to six early ORD comparisons he was able to research topic, the investigation of curare productive years as an assistant and almost derive the uniform configuration of the alkaloids, began in 1945 and ultimately ten years as an active emeritus Professor, amino-substituted carbon atom and demon- continued in close collaboration with H. Karrer produced a truly impressive body strated the same configuration in alkaloids, Schmid and a large number of assistants of work, which due to its range and vari- e.g. in nicotine. The investigations into the and reached a new highpoint in scientific ation through many very different fields synthesis of amino-alcohols by reduction of knowledge and at the same time mod- can only be described here fleetingly. amino-carboxylic acids and their use in the ernisation of laboratory techniques at the Karrer’s biography contains 1042 original production of local anaesthetics e.g. ‘Pan- Institute. This field was continued far publications in scientific journals, includ- thesin’ (patents 1920 and 1922) directly beyond Karrer’s retirement and brought ing review articles and conference reports. evolved from the above research. stimulating new ideas for the entire field In addition he authored 78 patents. The The most comprehensive series of in- of alkaloid chemistry. The same can be ‘Textbook of Organic Chemistry’ that was vestigations with a common theme was the said for other areas of research that Kar- published in 14 editions between 1927 and ‘plant dyes’. This work began in 1927 and rer undertook or initiated. In 1932 George 1963 and translated into seven languages formally ended in 1935 with the 63rd pub- Wald, a postdoc, isolated vitamin A for should not be forgotten as well as the lication. At the beginning were the inves- the first time from the retina of oxen and monograph ‘The Carotenoids’ which he tigations into anthocyanine, the red water- thereby started the structural research into cowrote with E. Jucker. Karrer revised his soluble dye contained in many flowers and retinal pigments. When, in 1946 the first textbook incessantly and − with respect to fruits. Improved separation techniques and results into the composition of the mysteri- content − adapted it to reflect new results. degradation methods enabled Karrer and ous glucoside aucubine (with H. Schmid) It is internationally one of the most suc- his coworkers to determine the structures and verbenaline (with H. Salomon) were cessful textbooks in chemistry ever. of many anthocyanines. Together with Ri- published, none of the collaborators could The topics of the publications of Kar- chard Willstätter and Robert Robinson, have imagined that they had laid the foun- rer and his group between 1912 and 1925 Karrer was one of the recognised creators dations for a new chemistry of the group reflect the influence of P. Ehrlich’s intro- of classic anthocyanine research. of iridoids. duction of modern chemotherapy and the Polyene dyes of the terpene series were Palustrine, the toxic alkaloid extracted impressive work on natural products by investigated at the same time. The first from march horsetail, was the first spermi- the great Emil Fischer. Much later Kar- publication (1927) concerned the saffron dine alkaloid to be isolated in pure form rer spoke to me of Fischer with great re- dyes crocin and crocetin. From there Kar- in 1948. In 1951 fuerstion the first plant spect. Initially research on physiologically rer progressed to become the internation- dye with a diterpene structure followed. active arsenic and bismuth compounds ally recognised master of natural product To conclude the pteridines are mentioned, dominated. This was directly connected chemistry in only a few years: that were later further developed by the to ‘Salvarsan’ (Ehrlich, 1910), the correct Viscontini group and were to become a structure was however only determined 1928 Correct symmetrical formula of significant group of therapeutic potential many years later. At the same time Karrer crocetin that even today has not been fully over- worked on the structure elucidation of al- 1929 cis/ trans-Isomers of bixines viewed. kaloids (emetine and sanguinarin groups). 1930 Structures of lycopene, β -carotene, Synthesis of arylketones, partially in con- luteine, zeaxanthine, squalene, Honours and Activities nection with vermicidal filicic compounds chromatographic separations Karrer was honoured many times for followed. Synthesis of glycosides were ex- 1931 Isolation and structure his pioneering research. He was awarded tensively investigated in addition to more determination of vitamin A the highest scientific prize in Switzerland, tentative examination of quinic acid, quer- (axerophthol) the Marcel Benoist Prize, in 1923, this citol, glycyrrhetinic acid, tanning agents, 1935 Synthesis of vitamin B 2 was followed by the Cannizzaro Prize of amyloses, inuline, suberine (cork fat), and (riboflavine); carotenes in the Italian Chemical Society in 1935 and, chitin. Despite some encouraging results photosynthetic bacteria the high point, the Nobel Prize in 1937. In (in addition to some wrong conclusions) 1938 Synthesis of vitamin E 1947 Karrer was elected as ‘Foreign Mem- these publications do not make a lasting (tocopherol) ber of the Royal Society’ and in 1954 ‘Of- impression on the reader, disregarding 1939 Isolation of vitamin K 1 ficier de la Legion d’Honneur’. No fewer subsequent developments, since the work (phylloquinone) than 15 Universities awarded him honor- tended to be fragmentary and did not pro- 1942 Structure of NAD + ary doctorates and an even larger number vide any new insights. (‘codehydrogenase’) ofAcademies and scientific societies made One of the first specialities was Karrer’s 1945 Discovery of carotene epoxides; him an honorary member. Despite all publications on polysaccharides ( ca. 50 ar- partial synthesis these honours Karrer remained the same ticles between 1920 and 1930 on starch, 1950 Synthesis of β -carotene reserved and modest scientist, although he cellulose, inuline, glycogen, lichenine, 1955 Pterines from Drosophila was happy to accept the honours awarded chitin, xylan). These articles brought him 1958 Structure of toxiferine to him. Karrer was an active participant in international recognition − but neither (curare alkaloid), synthesis of many committees; president of the Swiss Karrer nor any other specialists in the field canthaxanthine Chemical Society (1924− 1926), the Zurich 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 87 CHIMIA 2008, 62, No. 3

Society for Natural Sciences (1928− 1930), for prospective school teachers, by Ernst B. acid) and the synthesis of sulfonamides with the Stipendienfonds of the Swiss Chemi- H. Waser. Gränacher was a former student pyridine substituents.[77] cal Industry (1944− 1967), member of the of Dubsky, who then worked as an assistant Gerold Schwarzenbach followed Grä- editorial committee of Helvetica Chimica for Werner and Karrer and taught part-time nacher as section head (winter semester Acta (1924− 1971), Dean of the Philosophi- at the secondary school in Rafz and at the 1930/31). His research interests are de- cal Faculty II (1928− 1930), Rector of the Zurich grammar school. In winter semester scribed in Section 12. University (1950− 1952) and president and 1920/21 he completed his habilitation in Robert Wizinger was appointed in sum- organiser of the International Union of Pure organic chemistry. Gränacher’s scientific mer semester 1938 as senior lecturer and and Applied Science Congress which took work was concerned with improvements in titular professor. He was awarded his doc- place in 1955 in Zurich. Pregl’s microanalysis of halogen-, sulfur-, torate at the University of Bonn in 1924 Since 1959 a foundation created by and nitro-containing compounds. His ma- under the supervision of Prof. Pfeiffer and leading companies of the Swiss chemical jor area of research later was investigations completed his habilitation in 1934. Shortly industry has kept alive the memory of this into the oxidation of paraffins to fatty acids after being promoted to associate professor great research scientist at the University and the reaction of rhodanin with a range of in Bonn he was dismissed for political rea- with the ‘Paul Karrer Lecture’.[75] electrophiles to form dyes. When the Erzie- sons and arrived as a penniless refugee with It is difficult, if not impossible, to com- hungsdirektion turned down the proposal of his family in Switzerland. The appointment pare Karrer’s lifelong achievements with the Faculty to elect him associate professor as section head and a new habilitation for those of his teacher Werner. The differences in 1928, he transferred to Ciba where he the field of ‘organic chemistry and organic in personal and scientific respects are too soon made an impressive career. technology’ enabled him to continue with large. Despite that it is clear that Karrer took Ernst Waser completed his doctorate his academic career. In summer semester over much more from Werner than is gener- with Willstätter at the ETH on the synthe- 1943 he was elected associate professor. ally supposed. However the difference lies sis of cyclooctene derivatives from pseu- Wizinger hesitated for a long time whether in the fundamental nature of the topics that dopelletierine and after working as an as- he should take up the offer of the Chair in the two scientists chose to work on. Werner sistant to H. Wieland (Munich) and Cloetta the newly created Institute for Dye Chem- developed very early on a comprehensive (pharmacology, University of Zurich) took istry at the University of Basel, particularly concept for the structural understanding of a position as chemist at the ‘Allgemeine because Karrer and the Faculty were at- a large but neglected field of chemistry and Maggi-Gesellschaft’ in Kempthal. He com- tempting to improve his research facilities. built upon this basis a lifelong with tenacity. pleted his habilitation in winter semester In 1947 Wizinger accepted the position in It is difficult to imagine inorganic chemis- 1921/22 in organic chemistry and was then Basel and left Zurich. try today without the influence of Werner’s appointed as part-time lecturer for the prac- Wizinger brought a new style of work- reasoning. Economic considerations were tical course for teacher training candidates, ing to Zurich, which differed greatly in obviously not what drove Werner and he did before being promoted to department head. its casual manner to the strictly organised not seek practical application of his work. Waser also lectured on food chemistry at the Karrer. However many PhD projects under The so-called ‘relevance’ of Karrer’s ETH. The appointment as Cantonal Chem- his supervision dragged out so much that it achievements is obvious; in his bigger and ist (1928) and the part-time professorship became difficult for some to bear. Wizinger more sensational research it was always the for food chemistry (1930) enabled him to also had a tendency to publish the results of proven or proposed biological activity of satisfy his desire for a responsible position his students very late or sometimes not at target compounds that inspired him to in- in public office and his preference towards all. As a lecturer he filled us with enthusi- vestigate. For this reason the influence of university teaching simultaneously. asm with his lectures on aromatic chemistry Karrer’s research on the development of the Waser lectured at the University on a thatwerepepperedwithhumoroushistorical chemical industry is evident. wide range of subjects (technology, dyes and reminiscences. The Monday evening tutori- Who could decide which fundamental pigments, alkaloids, food chemistry, protein als on synthetic chemistry were also very quality for a university professor is the more chemistry, synthesis of pharmaceuticals, het- popular. These were continued, in a differ- significant or perhaps more far-reaching? erocycles, water- and wastewater purifica- ent format, by H. Schmid and are today part Both Werner and Karrer, each in his own tion, and a course on dyeing techniques). His of the advanced chemistry programme. time, made his field flourish, both were ac- research concerned principally hydrogena- Wizinger’s scientific interests were knowledged experts of their respective spe- tion, decarboxylation and synthesis of aro- mainly focussed on dyes: mechanism of cialities and both offered research topics that matic amino carboxylic acids. His premature azo-coupling, synthesis of formazans, tri- held great attraction for young chemists. death in 1941 left behind a great void.[76] arylmethanes, flavylium salts, cyanine and The successor to Waser for the position hemicyanine dyes. He was the first to de- of section head was Karl Wilhelm Nägeli. scribe correctly the ionic mechanism of 9. Professors at the Institute of He began his dissertation in Werner’s group bromo addition to olefins. Chemistry at the Time of Karrer and completed it with Karrer in 1921. After Robert Schwyzer obtained his doctor- a position as Ramsay-Memorial Fellow at ate with Karrer in 1948 and his habilita- After the departure of the last lecturers the University of Oxford and research on tion in summer semester 1951 for special that had habilitated under Werner, and after physical chemistry topics under the supervi- fields of organic chemistry. His successful the retirement ofAbeljanz, the path was free sion of Prof. Lambert he returned to the Uni- teaching and research activities were not for the creation of a Chair in the Depart- versity of Zurich and made his habilitation interrupted by his move to Ciba in March ment of Physical Chemistry (Henri’s ap- in chemistry in winter semester of 1925/26. 1952. Schwyzer introduced the new and pointment had already been confirmed at an Nägeli wrote a short textbook of chemistry pioneering field of peptide synthesis to the earlier date) and the Sections A and B were for medical students in which he attempted research spectrum of the Organic Chemis- united under a single Institute Director. Two to introduce modern electron theory of the try Institute. When he was elected Professor positions as departmental heads were creat- English School (R. Robinson, Lapworth for Molecular Biology at the ETH in winter ed from the associate professorships for, the etc.) into the German language. His sci- semester 1963/64 he discontinued his lec- one hand, the practical teaching for medi- entific interests were aimed at the Curtius tures at the University. cal students and this post was occupied by degradation and its application to structural The research of Prof. Hans Eduard Charles Gränacher in 1924 and the other, problems (perhydronorbixin, chaulmoogric Schmid is described in Section 13. 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 88 CHIMIA 2008, 62, No. 3

10. Physical Chemistry from Victor in 1897. Whilst working as an assistant at up to serve in the ‘Recherche scientifiques Henri onwards the Sorbonne with the physiologist Dastre appliquées à la défense nationale’ and took he began to turn increasingly to aspects of over a laboratory at the ‘Ecole de Physique Background physical chemistry. After the outbreak of et Chimie’ in Paris. After the French front When Pfeiffer was appointed as associ- war he was sent to Russia in 1915 on an collapsed, the laboratory received the order ate professor at the beginning of the summer official mission to help rebuild the chemi- (12.6.1940) to move to Toulouse. Behind semester 1908, his contract specified teach- cal industry. The Russian revolution caused the retreating army, Henri, who was by now ing ‘physical and theoretical chemistry’.Af- him to abandon this mission and he returned seriously ill, reached La Rochelle with his ter his departure this area was initially left to France. From then on he concentrated on family after much difficulty and died there vacant. From winter semester 1914/15 Dr. photochemistry and quickly gained interna- on 21st June 1940. Israel Lifschitz began to lecture on topics tional recognition for his research. His contempories described Henri as an of physical chemistry principally in courses In Zurich Henri began by lecturing on artistic type with irresistible charm, who that Karrer had newly defined. ‘General Physical Chemistry’ and ‘Appli- did not take the normal concerns of every- On 5th January 1920, the Erziehungs- cations of Physical Chemistry in Biology, day life as seriously as was expected by oth- direktor Mousson asked the Philosophical Catalysis and Fermentation Reactions’. He ers: invoices were thrown unpaid into the Faculty II to make proposals for the suc- also organised practical courses in physical wastepaper bin and he often did not bother cessor to Abeljanz (see [74]). The Faculty chemistry for chemists and biologists. Un- to answer letters, despite this, no-one could tried initially, without success, to attract der his supervision around 20 dissertations manage to get seriously angry with him. Dr. Arthur Stoll, head of the pharmaceu- were completed that were almost all con- One of the early students of Henri was tical department of Sandoz in Basel[78] cerned with his photochemical research. Werner Kuhn (1899− 1963) who was award- (organic chemistry!) and then applied to Henri extended the quantitative methods ed his doctorate in 1926 with a dissertation not appoint anyone for the time being and for molecular spectroscopy. Many absorp- entitled ‘L’équilibre chimique thermique au to amalgamate Sections A and B to a sin- tion spectra in the liquid and gas phases point de vue cinétique et photochimique’. gle one under Karrer. At the same time were measured. With time proven concepts He spent the years 1924 to 1926 with Niels an extensive reorientation of the teaching on the correlation between structure and Bohr in Copenhagen on a Rockefeller Fel- of physical chemistry at other Swiss uni- electronic spectra were developed, known lowship. After his return he completed versities was being undertaken.[79] Kar- today as chromophores. This research was his habilitation in physical chemistry in rer emphasised in an expert opinion the greatly significant for the organic chem- summer semester 1927. He lectured on necessity of creating a Chair in Physical ists who had started in the middle of the ‘Absorption and Dispersion and their Re- Chemistry. The following candidates were 1920s to tackle the structure of polyenes (P. lationship to Chemical Structure’. He did considered: J. E. C. Timmermans, Brus- Karrer, R. Kuhn). Henri discovered inde- not lecture further because he was sent on sels; E. Briner, Geneva; A. L. Bernoulli, pendently from Bodenstein that there were leave. In 1928 he made his habilitation at Basel; and E. H. Büchner, Amsterdam. photochemical reactions in which a large the University of Heidelberg and worked as Büchner was put forward by the Fac- number of molecules reacted per quantum assistant to Freudenberg who at that time ulty for the Chair but was turned down of absorbed light. Today these are classified was working intensively on the empirical by Mousson after a personal interview. as chain reactions. Henri also discovered treatment of optical activity for the assign- On 28th May, Mousson put forward the the phenomenon of ‘predissociation’in mo- ment of configuration. Many publications name of Victor Henri and requested the lecular spectra, which showed a continuous on ORD and CD measurements originate Faculty to discuss his suggestion. Henri transition from line to band spectra. from this period. Later Kuhn became asso- had been proposed to him by the Coro- At the beginning of 1927, Henri was a ciate professor at the Technical University ner, Prof. Zangger. Recommendations for guest lecturer at MIT, Cambridge, USA. In Karlsruhe (1930) and then full professor Henri were written by Pierre Weiss (Stras- 1930 he resigned his professorship and be- at the University of Kiel (1936) and Basel burg), Jean Perrin (Sorbonne) and Pierre came the director of an industrial research (1939).[83] Langevin (Collège de France).[80] On 30th institute in Berre (South of France). After a When Henri resigned in Zurich, Kuhn July 1920, the Faculty put forward a pro- short time he moved to a professorship at the was discussed as a possible successor; posal for primo loco Dr. W. Treadwell, University of Lüttich. In 1939 he was called however his name was not put forward Professor at the ETH, and secundo loco by the Faculty. Hans Ritter von Halban[84] Dr. Victor Henri, Paris. Since Treadwell (1877− 1947) (Fig. 15), a physical chem- declined the Chair, Henri was appointed ist who originally came from inorganic associate professor for physical chemis- chemistry was appointed instead. His dis- try on 15th October 1920 and at the same sertation, under the supervision of Werner time given two assistant positions and a in 1902, was on complex chemistry and respectable budget for equipment.[81] entitled ‘Investigations of Chromium Am- monium Compounds’. Von Halban then Victor Henri[82] worked for five years with W. Ostwald With this bold appointment, the Univer- and M. Le Blanc in Leipzig. He made his sity gained an open-minded and versatile habilitation in 1909 at the University of scientist who founded a school of spec- Würzburg in physical chemistry. When war troscopy in Zurich that can be considered broke out, as an Austrian, he was called up amongst the best in the world (Fig. 14). to serve as an artillery officer initially at the The son of a French man and a Russian front and then after sustaining serious in- woman, he spoke both languages fluently. jury, in the ‘Scientific Committee for War He grew up in Marseille, Sebastopol, Riga Economy’ in Vienna. In 1919 he returned and Petersburg. With 15 he moved to Paris. to the University of Würzburg where he had He studied physiology under Binet at the been appointed associate professor in 1915. Sorbonne, was awarded his doctorate with In 1925 he became the head of research at a dissertation on physiology in Göttingen Fig. 14. Victor Henri the ‘Metallgesellschaft Frankfurt a.M.’; in 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 89 CHIMIA 2008, 62, No. 3

1924 he turned down a professorship at the number of his students who subsequently low-temperature physics. In Leiden he dis- University of Bonn but he was happy to ac- became university lecturers is astonishing covered the lambda point of liquid helium. cept the position of Henri’s successor (win- high: L. Ebert, J. Eisenbrand, K. Rast, G. In 1930 he made his habilitation at the Uni- ter semester 1930/31). With the appoint- Kortüm, B. Szigeti, K. Wieland. versity of Göttingen, was appointed as as- ment of von Halban the Institute of Physical In summer semester 1935 Felix Almasy sociate professor in 1934 at the University Chemistry as an independent institute was made his habilitation in ‘physical chemi- of Würzburg and full professor in 1936 at established. In contrast to his predecessor cal biology’ at the Faculty of Veterinary the University of Munich as the successor his talents lay less in the discovery of new Medicine with a laboratory in the Physical to Kasimir Fajans. effects as in the perfection of measurement Chemistry Institute. He was a student of Clusius’ scientific work comprises ap- techniques and the careful interpretation of Henri’s and had been awarded his doctor- prox. 300 publications. The contents can measured data. ate in 1933. His interests were in absorp- only be summarised briefly here: low- Von Halban’s research concentrated tion, fluorescence and Raman spectroscopy temperature calorimetry, proof of the free on: optical precision methods to determine of biologically important molecules. Karl rotation of a molecule in a solid, kinetics of the concentration of weak electrolytes; im- Wieland made his habilitation in summer chain reactions, thermodynamic measure- provement of quantitative spectrophoto- semester 1941. He was originally an ex- ments on D 2 and HD, determination of the metry by the introduction of noble-gas perimental physicist who established by nuclear spin 1 for D, phase transitions in filled light-sensitive alkali cells; investi- spectroscopy the existence of radicals in solid CH4 , CH3 D, CD4 , PH3 , SiH4 , GeH4 , gation of the dissociation equilibria and gas equilibria at 800− 1200 °C. He also in- H 2 S, D 2 S, H 2 Se, D 2 Se etc. Clusius became determination of dissociation constants of vestigated extensively the thermal transfor- known for the invention of the thermodif- weak electrolytes (phenols); investigation mation of azulene into naphthalene. fusion column (Trennrohr) with which gas of the phenomena of ion pair formation Klaus Clusius (1903 − 1963) (Fig. 16) mixtures could be separated, and in the in- and ion association by means of spectros- was appointed as the successor to von Hal- genious apparatus, thermodiffusion could copy; kinetics of rapid reactions in the liq- ban in winter semester 1947/48.[87] With be multiplied to such an extent that the pure uid phase with a flow method; influence of this appointment the University gained an isotopes could be separated (Fig. 17). The solvents on reaction kinetics and on equi- internationally recognised expert in ther- first experiment and the one that brought libria; polarography of organic substances. modynamics and kinetics, who gave the Clusius international recognition was the He worked for almost 40 years on the pho- somewhat sleepy Physical Chemistry Insti- separation of H 35Cl and H 37Cl. Further toreaction of 1,1,2,2-tetrabenzoylethene, tute new impetus and quickly made it into separations of 20Ne/21Ne/22Ne, 84Kr/86Kr, ultimately together with H. Schmid, who an active and stimulating centre for modern 18O, 15N, 36A/38A, 13C followed. Some of had made substantial contributions to the physical chemistry research. The changes, these separations were enormously time- structure determinations of individual as is often the case, were not easy for the consuming and took years. The pure iso- products and received an introduction to organic chemists and I still remember the topes were not only used for precise ther- photochemistry. [85] slight unease, as a former student of von modynamic measurements but were also To us students H. von Halban was a Halban, with which I approached the ex- available for general use, e.g. 86Kr was friendly but rather reserved person with a amination in physical chemistry with Clu- used as a new unit length measurement and noble behaviour. In later years he lectured sius whom I barely knew at the time. to determine the age of minerals. No fewer sitting down due to a heart problem. He Clusius gained his doctorate under the than 40 publications were written on the 15 died one week before his official retire- supervision of A. Eucken in Breslau in production of N 2 and its derivatives. The ment. During his time only twelve disser- 1928, and then went as a Rockefeller Fel- tations were completed; organic chemistry low to C. N. Hinshelwood in Oxford and under Karrer proved to be so attractive that later to W. H. Keesom in the Kammerlingh- very few students chose physical chemistry Onnes Laboratory at the University of Lei- as their specialist subject. Despite this the den where he first came in contact with

Fig. 17. Thermal diffusion columns for the Fig. 15. Hans von Halban Fig. 16. Klaus Clusius separation of isotopic gases 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 90 CHIMIA 2008, 62, No. 3 thermodiffusion columns were used to pro- Hannover and honorary member of many 15 15 15 duce NH3 , H NO3 , H NO2 and these scientific academies. reagents were applied for the first time for Shortly after the death of Clusius, his the determination of structures and reac- coworker of many years, Kuno Schleich, tion mechanisms. The following examples completed his habilitation in the summer give an overview: semester 1964. He took on the interim di- − In the Fischer indole synthesis from rectorship of the Institute. His research in- arylhydrazone ( 19), the hydrazone-N terests were the low-temperature separation was cleaved as ammonia. of isotopes, and calorimetry and thermo- − The diazotisation of phenylhydrazine analysis of isotopic gases. He left the Uni- ( 21) to produce the isotopomeric phe- versity the same year and took up a post in nylazides ( 22 and 23). For the interpre- industry. tation a protonated three-ring derivative Heinrich Labhart (1919− 1977) (Fig. (triazane) was proposed. 18) was appointed as the successor to Clu- − Alinearpentazene( 25)andaphenylpen- sius in winter semester 1964/65.[88] He was tazole ( 26) were postulated as interme- originally a solid-state physicist and had diates in the synthesis of phenylazide completed his dissertation under the super- from phenyldiazonium salt ( 24) and vision of G. Busch and P. Scherrer at ETH azide ions; these were later isolated. in 1947. Then he took a scientific post at − The linear structure of arylazides, dia- the Medical Clinic of the University Hospi- zomethane and diazoacetic ester was tal of the Canton of Basel where he worked proven. on the improvement of electrophoretic − In the synthesis of azides from sodium separation of proteins, amongst other top- Fig. 18. Heinrich Labhart amide and N 2 O, the isotopomeric azides ics. From 1951 he worked in the physics ( 28 and 29) were formed, possibly via a department of Ciba in Basel. Besides that symmetrical intermediate (Scheme 10). he made his habilitation at the ETH (SS soon gave the Institute a new direction. This Clusius was a stimulating teacher and 1952) and in 1954 also at the University of was a reorientation in modern spectrosco- excellent speaker with great charisma. In Basel. In 1958 he was appointed part-time py, which was not greeted with joy from the short time that he worked in Zurich, 35 associate professor at the University of Ba- all participants. Research concentrated on: students were awarded their doctorates. His sel. He held lectures on solid-state physics electrochromic phenomena, determination excellent experimental skills enabled the and quantum chemistry. A research visit in of dipole moments of excited molecular construction of complicated apparatus such 1956 of several months at the University of states, the σ , π interaction and the calcula- as in his famous experimental lectures with Chicago brought him into contact with the- tion of the charge distribution in heterocy- flames or liquid hydrogen. As a discussion oretical chemists such as Robert Mulliken cles. Labhart’s interests moved increasingly partnerheimpressedwithhisgreatscientific and John Platt. In 1960 he took over a new towards the investigation of primary photo- knowledge and his broad knowledge of his- group at Ciba for dye molecular physics. chemical processes and the complex paths tory. His opinion carried great weight in the His work on the optical behaviour of mol- that electronically excited molecules return Faculty. As Dean he played a decisive role ecules in electric fields, which gained him to the ground state. Also photoreactions on in the appointment of the successor to Kar- wide recognition, originated from this time. aromatic heterocycles were investigated in rer and the reorientation of the Institute of He was also interested in the developments a close collaboration with the photochem- Chemistry. Clusius received many honours: in quantum chemistry. In 1964 he received istry group of Hans Schmid. he was awarded the Cannizzaro Prize, the almost simultaneously offers from the Labhart fulfilled his duties very consci- Marcel-Benoist Prize, the Dechema Prize Polytechnic of the University of Lausanne entiously. His five-volume ‘Introduction to and the Mario Giacomo Levi Prize. He was (EPUL) and the University of Zurich. He Physical Chemistry’ is a sign of his teach- elected Dr. h.c. of the Technical University decided in favour of Zurich. In Zurich he ing skills. To outsiders he always appeared reserved; he was never intrusive. His deeply friendly and cheerful nature and his well- balanced judgement in all scientific ques- tions made him a respected and liked col- league and teacher. It is tragic that he did not live to experience the new Physical Chemistry Institute that he had planned so intensively. But Labhart had organised the Institute in such a way that his death did not leave such a vacuum that earlier premature deaths or retirements had done.

11. Rämistrasse 76 and the Expansion

In Section 4 the construction of the Chemical Institute building was described. It sufficed until the beginning of the 1930s when the number of students began to in- crease steadily; from then on renovations Scheme 10. proceeded at ever-decreasing intervals: 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 91 CHIMIA 2008, 62, No. 3

search in NewYork as a Rockefeller Fellow 1931 Storey added for a laboratory to work with L. Michaelis and then to L. for medical students. Pauling in Pasadena. This stay in America 1946 Another storey added to had a great influence on the development extend the Physical Chemistry of Schwarzenbach’s scientific interests. Institute. Further positions followed: 1943 associate 1956 Wing of the ‘Oberrealschule’ professor for analytical chemistry and 1947 (Rämistrasse 74) taken over; full professor for ‘Analytical Chemistry and extension of the library. Special Fields of Inorganic Chemistry’. 1957/58 Renovation of the basement, Schwarzenbach resigned on 31st March construction of an intermediate 1955 to take up the position as Treadwell’s floor, construction of successor at the ETH. new workshops and labs During his 25-year activities at the Uni- for chromatography, N 2 versity, his reputation as a scientist and condensation etc. teacher steadily increased. Despite this he 1965 Rebuilding of the inner only had contact with the students during courtyard with the construction Fig. 19. Schönleinstrasse 2 practicals and special lectures since Karrer of two underground floors. held the main lecture course on inorganic 1966 Take-over of further parts chemistry until his retirement. In addition of the ‘Oberrealschule’, Faculties:[89] the German Seminar, the Insti- most of the students were well aware that in particular for mass tute for Medical Genetics, the Institute for Karrer did not tend to ask questions in in- spectrometry labs. Mathematics and Applied Mathematics, organic chemistry, neither in the written 1966/67 Take-over of a further wing Northern Philology, Pedagogic Institute, nor the oral final exams. This odd situation of the ‘Oberrealschule’, for the language lab, television services and caused great unease both within and outside the extension of the Physical the audiovisual department of the Univer- the Institute but there was no-one with the Chemistry Institute and the sity. The parts of the Biochemical Institute authority to persuade Karrer otherwise. Kar- library. that occupied the former ‘Oberrealschule’ rer − and not only he − did not seem to have Extension of the house on moved together with rest of biochemistry recognised the objectives that Schwarzen- Schönleinstrasse 2 (Fig. 19) to the Irchel. bach was following with his extensive acid- for the solid-state lab of the The building on Schönleinstrasse 2 is ity measurements, since it appeared to be Inorganic Chemistry Institute now used by the Dentistry Institute. no more than a special method of physical and later for the organometallic chemistry which, even if different, had al- and complex chemistry group ready been done by von Halban. Although of Prof. H. Werner. 12. Inorganic Chemistry from Schwarzenbach’s textbook of ‘General and 1969 Renovation of a further wing Gerold Schwarzenbach onwards Inorganic Chemistry’ (1st edition in 1941) of the ‘Oberrealschule’ on the wasgreatlyappreciatedbythestudentssince 3rd floor for practical sessions For chemists of the current genera- it put general concepts before extensive in the Organic Chemistry tion as well those at the time the name of facts, it was criticised heavily by specialists Institute and for the Medical Schwarzenbach is so closely associated for obvious and perceived errors. It should Laboratory. with the renaissance of inorganic chemistry be remembered that Schwarzenbach only 1973/74 New living space for the in the German-speaking countries that many became known to wider circle of chemists janitor, the Pedagogic Institute, readers will react with disbelief to find out from 1945 onwards. If Schwarzenbach had the Linguistic Department that during the entire time that Schwarzen- had the patience to wait for Karrer’s retire- of the German Seminar, the bach was at the Institute, there was no in- language lab, the Biochemical dependent Institute of Inorganic Chemistry. Institute and the external It has already been mentioned in Sections 8 station of the Computing and 9 how the lecture courses were divided Centre. amongst the professors in the Department 1979 Assignment of new rooms for of Physical Chemistry and the two positions the Biochemical Institute. of section head. After Gränacher’s resigna- tion, Gerold Schwarzenbach[90] (Fig. 20) This short chronological summary omits was appointed as his successor (1.1.1931). the many small renovations and alterations. He had been awarded his doctorate under It shows how generously the authorities the supervision of W. D. Treadwell at the reacted to the growing number of students ETH in 1928 with a dissertation entitled and the growing research requirements of ‘Studies of the Salt Formation of Mordant the Chemical Institutes. Even when the Dyes’ and then worked with W. Bradley in internal planning for the new chemistry R. Robinson’s group in Manchester and building started, necessary alterations were London on the synthesis of flavones and authorised and implemented. anthocyanidines. His habilitation in win- After the Chemical Institutes moved out ter semester 1930/31 concerned ‘the entire in summer 1978, the entire building was field of chemistry’. He published only one fundamentally altered. The large lecture article with Karrer on the specific acidity theatre no longer exists and a former stu- and the structure of vitamin C. A sabbati- dent would barely find his way around. The cal during the winter semester 1937/8 and total floor space of 7760 m 2 is now shared summer semester 1938 allowed him to go by one seminar and six institutes from four to the Rockefeller Institute of Medical Re- Fig. 20. Gerold Schwarzenbach 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 92 CHIMIA 2008, 62, No. 3 ment, he would have certainly gained his oped a special analytical procedure for me. als and then worked as Oberassistent and independent Institute of Inorganic Chemis- His tutorials in analytical chemistry were lecturer and took over the X-ray department try − and would probably been the succes- also popular. His dry and sometimes sarcas- and the electron microscopy lab. He worked sor to Karrer as well. tic comments were never insulting because as a postdoc at the Cavendish Laboratory, Schwarzenbach’s research encom- one felt that an superior brain was behind Cambridge, England, and in America. His passed many aspects: At the beginning he it all. habilitation in summer semester 1965 was attempted to produce a modern concept for In addition to his research in current on ‘Inorganic Chemistry and in particular the nature of acids and bases, with contri- scientific concepts Schwarzenbach later Solid-state Chemistry’. Crystal structure butions on substituent effects. Measure- became interested in the history of the de- analyses of hydroxide salts, chromium(II) ments of keto-enol equilibria with a sim- velopment of concepts in chemistry, e.g. the chloride, manganese oxide and research on ple flow apparatus yielded values that are acid− base concept and valence theory. He topotactic reactions of hydroxide-contain- still cited today. A new direction was taken received many honours: the Werner Prize ing phases of copper, manganese, and zinc when he discovered that cations can have of the Swiss Chemical Society (1936), the brought him wide recognition. a significant influence on the equilibrium Marcel Benoist Prize (1964) and many In Bern Oswald left behind a very well- in an investigation of a series of dyes in a medals; the Universities of Bern (1971) equipped laboratory and in Zurich not wide pH range, and that nitrolic triacetic and Fribourg (1974) elected him Doctor only had to rewrite the lecture courses in acid and ethylene diamine-tetraacetic acid honoris causa. inorganic and analytical chemistry but also showed a decrease in the pH when alkali When Schwarzenbach resigned from the had to plan and procure the necessary in- earth cations were added. This led to inves- University, his former student W. Schneider frastructure for his research. Many young tigations on metal complexes by means of took on the interim leadership of the analyti- chemists and technicians who had joined potentiometric measurements. A practical cal department, and E. Schumacher became him from Bern were an invaluable help in analytical technique was developed with section head. Schumacher had completed this undertaking. In Zurich the emphasis the discovery of specific metal indicators, his doctorate under the supervision of Clu- was placed on the new field of ‘solid-state e.g . eriochrome black T.[91] sius but then made his habilitation in ana- chemistry’, in particular the elucidation of At this time synthetic investigations lytical and inorganic chemistry in summer relationships between structure, morphol- also began to clarify the structural basis semester 1956. After Karrer’s retirement, ogy and reactivity. At first the structural for the ‘chelate effect’ in addition to many Schumacher was appointed as full profes- chemistry of hydroxide compounds domi- measurements of complex formation con- sor and the first director of the newly cre- nated but this soon broadened to include a stants. The results had a great influence on ated Institute of Inorganic Chemistry (win- whole spectrum of topics, different meth- biological, biochemical, limnological and ter semester 1959/60). Under his dynamic odology and investigated compound classes other concepts. leadership, research was oriented towards through to solid metal complexes. New pos- Schwarzenbach did not usually attempt physical-inorganic problems and there was sibilities were opened up by the installation to isolate the generally labile complexes. an impressive increase in the instrumenta- of modern thermoanalytical techniques for Despite this, to demonstrate a connection tion. This included rapid analysis of metal the quantitative study of energetics, kinet- with the research of A. Werner, the struc- ions by means of focussed ion exchange ics and mechanism of reactions in the solid ture of the chiral (!) EDTA-Ca2+-complex in an electric field, construction of a mass state. X-ray techniques and electromicros- 30 was determined (Scheme 11). spectrometer for many applications, geo- copy were also improved. After Schwarzenbach’s move to the chemical research on age-determination of The extra space that had been needed ETH, biological chelates such as ATP, meteorites, fluorine chemistry and the pro- for so long was finally provided by taking phosphoglycerinic acid and iron-complex- duction of noble gas fluorides. Schumacher over Schönleinstrasse 2 (see Section 11). At ing antibiotics were studied. Research on was the first at the University of Zurich to the same time planning began for the new protonation and deprotonation processes, use eidophor television projection of ex- institute building on the Strickhof site. An salt cryoscopy and polynuclear complexes periments into the large lecture theatre. His important personnel and scientific improve- of Cr(III), Co(III) etc., metal sufides and good connections to chemistry teachers at ment was achieved with the appointment of aromatic complexes with Hg was also per- schools and his great didactic skills helped Hermut Werner as assistant professor for formed. to modernise the introductory lectures. the beginning of winter semester 1968/69. Schwarzenbach was very popular It was a great loss for the new Inorganic He had gained his doctorate under the su- amongst the students. From my own time Chemistry Institute when Schumacher, dis- pervision of E.O. Fischer at the Technical as a student, I remember well his extensive appointed by the delays to his wishes for University Munich in 1961, and took a personal discussions on analytical prob- expansion, accepted an offer to become the postdoc position at the California Institute lems. As I was interested at the time in the head of research of photochemistry at Ciba of Technology, Pasadena, followed by ha- composition of an armoured steel, he devel- (1964).[92] In addition the appointment of bilitation at the TU Munich. his successor took so long that the further Werner began a successful series of in- development of the Inorganic Chemistry vestigations on the preparative synthesis of Institute came to a complete halt. The ad- complexes of transition metals, in particular ministrative duties and the introductory lec- those with sandwich structures, the kinetics ture course were performed in the interim and mechanism of substitution reactions of period by Dr. W. Ludwig (senior lecturer organometallic complexes, reactivity of since winter semester 1967/68) and other complexes with electron-rich metal ions lecturers from the Organic Chemistry In- and insertion reactions of metal-hydride, stitute. aryl and alkyl complexes. In a certain sense In 1966 Hans Rudolf Oswald was ap- this research could be considered a contem- pointed as the successor to Schumacher. He porary continuation of the early complex received his doctorate in 1960 at the Univer- chemistry of A. Werner. H. Werner was pro- sity of Bern under the supervision of Prof. moted to full professor already in 1970. He W. Feitknecht with the structural chemistry was active in the restructuring of the lecture Scheme 11. of hydroxide salts of the 3d transition met- courses. In winter semester 1975/76, to the 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 93 CHIMIA 2008, 62, No. 3 great regret of colleagues and the Faculty, chemistry at the II. Chemical Institute of the duction of modern spectrometry, he never he took up the offer of a professorship at the University of Vienna in 1941 with a disser- made the effort to learn to use the instru- University of Würzburg. tation under supervision of E. Späth on the ments so that he could measure a spectrum In summer semester 1970 A. Wytten- structure determination of natural cumarins himself. He always left the measurements bach completed his habilitation in radio- and dimeric aldol. His teachers were F. to his coworkers. chemistry and a year later R. Grauer com- Feigl, C. Mayr, F. v. Wessely, H. Mark and Schmid was a talented but not con- pleted his in inorganic chemistry. Both took E. Späth. After returning to Switzerland in ventionally brilliant lecturer. His lectures over lecture courses as external lecturers. 1942 he became assistant and then senior were impressive due to their content, clear They were followed by J. R. Günter (win- research assistant to Karrer. In winter se- structure and the conviction with which he ter semester 1976/77), E. Dubler (summer mester 1944/45 he completed his habilita- conveyed the material to his students. The semester 1977), S. Veptek (winter semester tion which was entitled ‘The Current State lectures never became routine, Schmid 1977/78); all three in inorganic chemistry of Biotin Research and Synthetic Experi- continually incorporated new results and and working full time at the Institute. ments in the Biotin Series’. modern concepts. During the entire time of J. H. Ammeter was appointed successor Impressed by the rapid expansion of his professorship he worked on improving to H. Werner in winter semester 1978/79. organic chemistry since the end of the Sec- his lecturing techniques and the content − He is a representative of theoretical-coordi- ond World War and the greatly increased and in doing so gained many PhD students nation chemistry and spectroscopy. In win- number of students, Karrer decided to from the undergraduates attending his lec- ter semester 1982/83 A. Salzer completed expand the small number of lecturers: H. tures. In the specialist lecture courses and his habilitation in coordination chemistry. Schmid and M. Viscontini were appointed later in the postgraduate courses assigned simultaneously as associate professors and to him, Schmid used the courses as an op- section leaders. portunity to read into a new field of study, 13. Organic Chemistry under the A research visit to M. Calvin in Berke- in which he quickly succeeded thank to his Leadership of Hans Schmid ley (1949), who was working at the time on ability to rapidly understand and assimilate CO2 -fixation in algae, introduced Schmid new material. I consider it a great honour to After Karrer’s retirement and after the to the 14C-technique. Later back in Zurich have been invited to share the introductory ‘division’ of the Institute of Chemistry, he developed the technique to a success- lecture course with him. Schmid’s ability Hans Eduard Schmid (1917− 1976) became ful method for the investigation of reaction to encourage the scientific development of the first Director of the Institute of Organic mechanism and biogenesis sequencing. his coworkers and to motivate them to high Chemistry in winter semester 1959/60. At Many of his former students in this field performances was always admired by his this time Schmid already had his own ac- were influential in introducing isotope lab- colleagues. His research group was known tive group of doctoral students. In addition oratories in many chemical companies. for its strong and cohesive work ethic. to Schmid, also with their own research When Schmid succeeded Karrer in Or- Schmid initially concentrated on the groups, were M. Viscontini (associate pro- ganic Chemistry, [94] he was able to calm isolation and structure of complex natural fessor since winter semester 1947/48), R. and settle the unavoidable tensions that had products, both from preference and as a re- Schwyzer, A. S. Dreiding and C. H. Eugster arisen with such a far-reaching change. He sult of his training in Vienna − disregarding (both senior lecturers since summer semes- often sought advice from his colleagues and the unsuccessful attempts to synthesise bi- ter 1955). their agreement in important reforms. He otin. He was barely interested in the organ- H. Schmid (Fig. 21) was born in Hend- attempted consciously to replace the aura isms that produced the substances. For many schiken AG, [93] but moved with his parents of respect that had surrounded Karrer with years Schmid carried out experiments him- at nine years of age to Vienna and went to a more natural approach to colleagues and self. In doing so he became an absolute ex- school there. He completed his studies in students. He also worked with great success pert. Many structures that were determined to improve the somewhat strained relation- at the time principally from interpretation ship between Chemistry at the ETH and the of clever degradation experiments can be University. considered as some of the best natural prod- Further improvements were made to the uct chemistry. They required, in addition to organisation and structure of the teaching; observational skill and experimental ability, theSaturdayseminarwasintroducedandthe a great deal of hard work on behalf of the colloquia were reactivated. In the research chemist involved. Schmid therefore was al- fields a careful and gradual expansion was ways careful to staff his research group with targeted, which was strongly tailored to motivated people. For this reason he never continuity and which showed no break gave up control over the teaching courses with the past. Schmid also modernised the that allowed him to judge the qualities of instrumentation and supervised many reno- up-and-coming students. These courses vations on the building and broadened the were, in particular, the preparative organic technical services. practical and the distribution of the Lite- Before his appointment as director, raturpräparat (which were often connected Schmid had already done much to improve with a particular problem of one of his as- the general laboratory skills in the Institute sistants) and the Hausprüfung that every and e.g. had brought along a valuable bulb practical student had to perform for him tube distillation method from Vienna and once he had satisfactorily completed one or improved it in Zurich. He had good skills more trial exams for a coworker. Schmid in microtechniques for isolation and puri- also retained responsibility for distributing fication of compounds and he often in later the assistant positions. For many years the years demonstrated his experimental abili- budget was used almost exclusively in his ties in laboratory courses. In this connec- own research group, and it required en- tion it is surprising to learn that although he ergetic intervention by the disadvantaged Fig. 21. Hans Eduard Schmid was one of the main initiators of the intro- lecturers to the Erziehungsdirektion to 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 94 CHIMIA 2008, 62, No. 3 change this situation somewhat to their exact determination of the process of mo- member and president of the Swiss Chemi- advantage. lecular transformation. They have become cal Society, president of the Swiss Commit- In later years Schmid’s research inter- significant for theoretical chemistry but tee for Chemistry etc. ests turned more and more to demanding are not easily explained in a brief review. Schmid loved to give lectures in other mechanistic concepts although the experi- Schmid used the 14C-labelling technique to countries; however the preparations and the mental work was never neglected. All the tag the migrating groups of atoms, which inclusion of the most recent results in the work that came out of his group is under- of course required a careful synthesis and lectures caused considerable agitation in standable down to the last detail. degradation plan. Key points of this re- himself and others so that he frequently re- The scientific work is contained in ap- search were: Proof of the intramolecular turned from such congresses both exhaust- prox. 480 publications. These show not nature of the Claisen rearrangement of al- ed and stimulated. Schmid was a popular only a wide range of topics but also a high lyl phenyl ethers; proof of the existence of discussion partner for the many visiting sci- information content. Schmid enjoyed fol- reactive intermediates by trapping reac- entists at the Institute. When the planning lowing different aims simultaneously and tions; explanation of the mechanism of the began for the new building on the Irchel he independently. The main interests were: anomalous Claisen rearrangement; discov- came under additional pressure that he was natural dyes, mechanistic studies, and pho- ery of the sigmatropic [3s,4s] and [5s,5s] able to reduce by delegation of individual tochemistry. Here only a brief description rearrangement; intramolecular Diels-Alder tasks to colleagues so that the deadlines is possible.[95] cycloadditions with rearrangement of aryl were able to be kept. The suggestion to work on the curare al- propargyl ethers and their acid-catalysed He was also depressed by the continually kaloids, particularly the so-called calebasse rearrangement to give tropylium salts. increasing number of publications in many type, came from Karrer. In an impressive The photochemical research originated different fields of chemistry that he wanted series of articles, which continued after in a collaboration with von Halban on the to follow in detail − no one from that time Schmid’s death, this chemistry developed photochemistry of tetrabenzoyl ethene (see can forget how he left the Institute every into an excellent example of what natural Section 10). Later it was shown that some evening with a briefcase filled with work. product chemistry was capable of at that curare alkaloids were photolabile and trans- He became increasingly concerned by time.[96] The curare project was started as a formed to other compounds that could also the declining number of chemistry students one-man project, but expanded continually be isolated from calebasses. Closer examina- and he was always occupied with finding until it occupied one of the biggest research tion revealed that irradiation of heterocycles measures to counter this phenomenon. groups in the Institute in which some of the with C − N double bonds not only resulted The final fatal heart attack on 19th most capable chemists worked. One should in oxidation but also reduction or that they December 1976 struck a scientist and col- not forget the background work that made bound to solvent molecules, e.g . methanol. league who had not yet reached the peak of this success at all possible: the acquisition This opened up a new field for Schmid of his abilities. of the many curare samples from South photochemical reactions in organic chemis- Hans Schmid left behind 35 cowork- America, the construction of suitable chro- try. Soon his research group had discovered ers whose personal, scientific and financial matographic systems[97] and continuous im- reciprocal rearrangement of heterocycles problems were dealt with care, patience and provement of the spectroscopic methods. In with two hetero-atoms under irradiation, not inconsiderable additional work by the 1956 it was shown that C 40 alkaloids, i.e. such as the transformation of pyrazoles into remaining colleagues and in collaboration dimers were present. In 1958 the relation- imidazoles, or isoxazoles into oxazoles etc. with Prof. Hansen (Fribourg). ship with indoles and in particular with Also the strained small-ring systems such After his death a collective Directorship strychnine was demonstrated.[98] Subse- as the azirines, whose multiple ground-state was created and the section leader positions quently one structure after another was pre- reactions were investigated principally by H. were discontinued. sented. One of the particularly impressive Heimgartner,becameaccessiblethroughnew results was the determination of the struc- and surprising photoreactions. They could be ture of the alkaloid villalstonine by means transformed into highly reactive ring-opened 14. Winterthurerstrasse 190 of degradation reactions and spectroscopy nitrile ylides which readily underwent addi- (1965). However almost simultaneously the tion to double bonds. This opened the way to The construction and the operational Americans Nordman and Kumra were able new five-ring heterocycles. design of the former ‘Chemical Institute’ to determine the complete stereostructure In 1964 Hans Schmid suffered his first on the Rämistrasse 76 were based on a low by means of X-ray structure analysis. heart attack, from which he rapidly recov- degree of specialisation, which was appro- Less spectacular but for many natural ered. Although he gave up his heavy smok- priate for the level of experimental chemis- product chemists no less significant were ing completely, his work rate could not be try of the time. With the increase in instru- the structure determinations of fluvoplum- curbed. To others it became clear that af- mentation, more and more dedicated rooms ierine (1953) and plumieride (1958). They ter this time he became more irritable and were required. In addition there were an were the first examples of structures from distrustful of some things which were not increased number of chemistry majors and a large group of substances known today immediately in connection with his own particularly students studying chemistry as as the iridoids. Later it became clear that interests. His restlessness increased and a subsidiary subject and the increasingly the glucosides aucubine and verbenaline, the remark “No time! No time!” was often urgent requirements of the Institute of In- that had been investigated much earlier but heard when he wanted to avoid a problem organic Chemistry for a modern laboratory. not particularly successfully by Karrer and that did not suit him. He also pointed out Section 11 describes how the authorities re- Salomon, also belonged to this group. The that he had to slow down when he wanted acted to the wishes of the lecturers for im- biogenetic relationship between the iridoids to protect himself from demands that he did proved working space. However it became and the indole alkaloids was shown by R. not want to accept. He must have suspected increasingly obvious that the University Thomas (1961), E. Wenkert (1962) and oth- that his time was limited. Despite this he had to undergo a fundamental expansion. ers. It is strange that the Zurich group, hav- did not reduce his workload even outside In spring 1960, the space requirements ing investigated both basis units, failed to his research group: He remained director of of Chemistry were clarified under order of recognise that they belonged together. the property Rämistrasse 74/76, president the Erziehungsdirektion. These formed the The mechanistic research of Schmid of the Widows, Orphans and Pension Fund basis of an internal report to the Cantonal and coworkers concerned principally the of the University Professors, committee Government on the expansion of the Uni- 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 95 CHIMIA 2008, 62, No. 3 versity. The government invited the Erzie- was at all possible; but Erziehungsdirektor ernised. The total amount spent on the first hungsdirektion to produce a general space- Dr. A. Gilgen adhered single-mindedly to stage of the University relocation was about requirement plan. The corresponding order the timetable. The relocation of the large 250 million sFr. [102] to the Institute directors from Erziehungs- instruments began directly after the end of Without doubt, the new building on the direktor Dr. W. König is dated 13th March the winter semester 1977/78; the summer Irchel site provides Chemistry with a mate- 1961. He demanded unequivocally that the semester 1978 was spent under reduced rial foundation upon which it can develop work be accelerated. In the same year the working conditions in Rämistrasse 76 and for the good of our country and for the ben- governmental Planning Committee started then the Institutes moved one after another efit of science. work. They came to the conclusion, as is according to a internal plan for the individ- It was therefore with concern that the well known, that the only suitable loca- ual research groups. Punctually for the start lecturers have observed over many years tion for the new buildings was the site of of the new semester, the lectures began in the decline in the number of students choos- the ‘Strickhof Agricultural College’ in the the new lecture theatres, but not without a ing chemistry as their major subject. There Oberstrasse quarter. It is less than three great deal of agitation for the lecturers in- are many factors to this and these have been kilometres from the main University build- volved. In contrast to the occupation of the discussed frequently.The teaching staff take ings and directly neighbouring to the Fac- new institute on Rämistrasse 76 (see p. 80) any well-grounded criticism seriously and ulty of Veterinary Medicine. A competition the professors, coworkers and students took attempt to improve the teaching and to offer for ideas was launched for architects both in over their new laboratories in a matter-of- new research fields. Chemistry as a science Switzerland and abroad in July 1965.[99] fact manner and without any sort of celebra- has always been associated with the inves- The referendum of 14th March 1971, in tions. The reasons for this sober behaviour tigation of the material basis of life and will which the partial relocation of the University were probably a result of many factors: two remain part of our culture and civilisation. together with a budget of 600 million sFr. was professors who had put great effort into the We hope that the recovery that has already voted on, resulted in an unexpectedly high planning of the new institute (H. Schmid occurred in other countries, will also reach number of votes in favour. It was the second and H. Labhart) had died in the past two our country soon. Cantonal referendum in which the women of years; the Zeitgeist and the lack of a student Zurich had been able to participate. chemistry society that identified itself with Then followed a period of intensive chemistry as closely as in earlier times; the 15. Looking Back and Forwards planning, in which all lecturers and senior modern purpose-built architecture and the research assistants were involved. The suc- new operational concept that replaced the The Chemistry Institute on the cessful planning was thanks to a large ex- old definition of an institution with clearly Threshold of the 150th Anniversary tent to the efforts of Dr. W. Frei, a former defined sections. In his retrospective[103] on the occasion senior research assistant. Objectively, it must be said that chemis- of the 200th anniversary of the Naturfor- Delays in the completion of the unu- try has gained excellently equipped rooms schende Gesellschaft in Zurich in 1946, P. sually large construction project (Fig. 22 for teaching and research; there are more Karrer stated: “In the last century and partic- and 23) resulted from the late relocation than 20,000 m 2 of space available, not ularly the past 60 years, chemical research of the Agricultural College, which forced counting the lecture theatres and the pub- in Zurich has reached a level and demon- a mirroring of the location of the Institute lic areas. The increase in the number of re- strated achievements that far exceeds what buildings along the main axis. The founda- search places compared to the old building could be expected for a medium-sized Uni- tion stone was laid for the first stage on 7th varies: in the Institute of Organic Chem- versity town. Fundamental discoveries in December 1973. A backlog in construction istry there is not much difference. Much our science will always be associated with due to the economic crisis and additional improved are number of dedicated rooms the name of our town… The high standard changes to the occupation plan of the In- for specialist use and the vast improvement of chemical research from the two academic stitute buildings[101] made those involved in infrastructure. Generous equipment bud- institutions in our town forms a significant doubt whether the proposed date for moving gets allowed the instrumentation to be mod- part of the foundation upon which a success-

Fig. 22. Winterthurerstrasse 190; part of buildings 32 (left) and 11 (right)

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Head 1963, 1963, 1968 1968 1960 1955 dir 1938, y) y) xtraord 959 section section TP Ap AP TP TP Ass. Ass. 1959 1969, 1973, tr 1947, dept. ETH str SL head (E s P1 us AP AP 925, ad nd 959, 955, 955, 951, 959, 966, 963, ) ,F nd 1930, and indu 1947; head he 1969) 1969) Pa 63 74 47 di L1 L1 D1 L1 L1 L1 L1 L1 ection fessor (locations, FP on 1980) (s (S (S (TP (P (S (S (PD (S (S FP 19 FP an 19 and (A (S 1966, 19 1969, 1983) ti dept. pro ec (SL te 1833 os and er tw tn enbach ing 6) cher AP directorship) rz zer of uer gster gar ssocia since ma 197 uli na Naegli on im zinger Eu Dreid 944, re ;† ti =a von Viscontini Hesse Ber He S. St Schwa lective H. W. Schwy Wi Schu ea 59 L1 ol AP Zurich (S 19 A. M. C. K. R. E. Cr W. Philipsborn M. R. H. G. C. H. 981) (c of P1 (A rius); te gster tu Philipsborn istry ti reiding Eu sella Ins .D Hesse von Schmid H. Va University (Ordina Chem H. W. M.Viscontini A.S C. M. A. stry the Institute mi at ganic ofessor 24 Or Che pr 19 1977 1978 ull er =f Chemistry 190 thur 3. FP 925 sse y: nter 59 .1 ble ra 19 ca Ke st Wi Ta 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 98 CHIMIA 2008, 62, No. 3 ful Swiss chemical industry could be built, Institute of Inorganic Chemistry E. Dubler and that is something that also benefits Solid-state chemistry aspects of bioor- society.” With this statement he was think- H. R. Oswald ganic chemistry: Using the experimental ing of the achievements of both Chemistry Research in solid-state chemistry with methods of solid-state chemistry (X-ray Institutes at the University and the ETH. emphasis on the relationship between the analysis, thermal analysis, electron micro- But it is also obvious in his speech that the crystal structure and the morphology scopy) substances in pathological biogenic contribution of the University is anything of solid materials on the one hand and solids such as gall stones, kidney stones but minor. However today we can expand chemical reactivity on the other. This re- or joint depositions are investigated. Tem- Karrer’s viewpoint somewhat: Since the quires the combined use of precise X-ray perature-dependent phase transformations, establishment of a ‘Chemistry Laboratory’ structure determination, light and elec- which occur for example in cholesterol more than 1200 dissertations in chemistry tron microscopy, and in particular highly have been observed and the proof of orient- have been completed, the first in 1847. sensitive quantitative thermoanalysis and ed growth of individual crystalline phases [104,105] Without doubt many of the gradu- mass spectrometry. This enables kinetic on other biogenic crystals (epitaxis). ates have entered various chemical indus- reaction processes in small crystals and In addition metal complexes with bio- tries, but also a considerable number have powders to be observed and mechanistic logically significant ligands such as uric sought other fields of work, for example: interpretations on the atomic level to be acid or sulfur-containing amino acids are patent law, food control, hygiene, medi- proposed. In addition to the ‘classical’ synthesised and characterised. cal laboratory, international organisations, solid-state systems ( e.g. hydrate salts, trade, schools etc. [106] During the time of hydroxides) coordination compounds of S. Veprek Werner and Karrer, teacher training was metals are investigated. The research par- Plasma chemistry, in particular solid- relatively neglected. It has been strongly tially presents models but also depends gas reactions in electric discharges; plasma encouraged since then. on the requirements of applied chemistry, chemical evaporation and deposition; sur- Let us also not forget the international e.g. thermochromism or improvement of face chemistry, preparation and characteri- collaborations, not only through the media the production of catalysts from suitable sation of amorphous semiconductors and of publications and congresses, but also by precursors. dielectrics. Restoration of antique metallic visiting foreign students that have spent one Further interests include crystal growth objects. or two years as postdocs in the Chemistry of substances for other research using a Photoelectron spectroscopy, mass spec- Institutes. Many of these have returned to range of methods and the study of certain trometry, thermogravimetric analysis. their homes as our friends. The textbooks solid-solid phase transformations (coopera- written by our lecturers have contributed tive Jahn-Teller effect in oxide systems and A. Salzer much to the transfer of knowledge. Let us complexes). Investigation of the structure and dy- also not forget the influence that chemis- namics of binuclear metal complexes with try has in other areas of University life: the J. H. Ammeter organic bridging ligands. Study of nucleo- training of apprentice laboratory techni- Description and rationalisation of rear- philic and electrophilic addition reactions, cians who carry out their training working rangements on the electronic level and the in particular stereo- and regiospecific C − C together with assistants and PhD students; measurement of the electronic structure of bonding on metal-coordinated di- and oli- many of these young people were inspired electronically and stereochemically labile goolefins. to further their studies at a polytechnic. metal complexes with modern spectroscop- The number of services that the members ic techniques and quantum chemical model of the Chemistry Institutes provide to the calculations. Institute of Organic Chemistry [107] programmes in medicine, biochemistry, biology, teacher training, etc. is also sig- W. Ludwig M. Viscontini nificant. So many structural and analytical Preparation and investigation of com- Metabolism of microorganisms (bio- chemistry concepts have been integrated plexes. In addition to preparative work and genesis of proferrorosamine from Pseu- into the fields of medicine and science that spectroscopic structure investigations, the domonas roseus fluorescens and a blue dye a basic chemistry training remains a neces- identification of the lowest electronic states from Bacillus mesenterius niger); synthesis sity. in inorganic chromophores is a major field of pyrrolizidin alkaloids; pteridine chemis- When we, on the threshold of the 150th of research in the group. try: synthesis of L -biopterine, tetrahydro- anniversary, think back with great pleasure L -biopterine, tetrahydro-L -folic acid and and justifiable pride over the achievements J. R. Günter derivatives. Tetrahydro-L -biopterine is the of the Chemistry Institute of the Univer- Topotaxis; chemical electron micro- coenzyme of the enzymatic hydroxylation sity since its foundation, we also have to scopy. At the heart of this research is the of the phenyl ring in L -tyrosine, L -DOPA acknowledge how much was due to the relationship between reagent and final etc. Biogenesis defects in humans result great commitment of our predecessors, the product in the reactions of solids. The field in atypical phenylketonuria, endogenic professors and their coworkers. We include of topotaxis is concerned with the crystal- Parkinson’s disease, endogenic depression in this acknowledgement also the authori- lographic-structural orientation of several and certain forms of schizophrenia. The ties which provided and expanded the basis phases simultaneously. High-resolution illnesses can be treated with oral doses of upon which Chemistry was able to grow electron microscopy is used to investigate tetrahydro-L -biopterine. and prosper. the micromorphology of multiphase reac- An overview of all the lecturers that tion products, i.e. the spatial distribution, A. Dreiding have lectured in chemistry since the foun- intergrowths and the structural relation- The aim of our research is the develop- dation of the University is given in Table ships between the product phases that result ment of simple model representations to in- 3. For reasons of space it is not possible to from a single phase reactant. Such results terpret the behaviour of material in its many include the current members of the three are applicable in metallurgy, ceramics and forms, also in biological systems. We study: Institutes, however for completion a brief materials science, mineralogy and hetero- components of plants and insects to discov- listing of their fields of research is given geneous catalysis. er new biosynthetic processes; synthesis below. of selected substances to characterise their 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 99 CHIMIA 2008, 62, No. 3 properties as chemical communication de- small rings; preparation of metal complex- Acknowledgments vices, drugs, dyes and as physical measure- es; use of 2H-azirines and 1-azetines for I would like to thank all my colleagues in ment devices; the use of energy-rich build- the synthesis of nitrogen-containing het- the Chemical Institutes for discussions and ing units for the synthesis of strained sys- erocycles. Synthesis of medium and large contributions, Frau B. Leissing (secretary of tems; the application of chemical symmetry rings by ring-expansion and ring-closure the Dean of Phil. Fac. II) and G. Graglia and principles to increase selectivity in targeted reactions. Photochemistry of heterocycles; A. Schumacher (Chancellery archives) for help in obtaining the documents. This publication reactions; the transferability of tried and production of reactive intermediates; regio- was made possible by a generous contribution trusted structural and mechanistic concepts and site-selective 1,3-dipolar cycloaddition from the ‘Dr. Emil Bindschedler Foundation in carbon chemistry to nitrogen systems; of nitrilium betaines. Synthesis and rear- in memory of Prof. Dr. A. Werner’. I thank the development of mathematical models to rangement reactions of sulfur-containing many people and institutions for the willingness describe and handle model structures. heterocycles. to provide me with photographs.

C. H. Eugster General comment: The personnel dossiers come Natural product chemistry (glandular Institute of Physical Chemistry from the University Archives and the Public substances from leaf glands of African labi- Record Office of the Canton of Zurich. Requests ates; dyes from russula mushrooms, isola- H. Fischer and H. Paul to the University Archives tion and structure analysis of carotenoids), Free radicals. In many chemical pro- [1] The ‘Carolinum’, former convent school separation techniques (high-performance cesses, including the primary processes of the ‘Grossmunster’; the new building liquid chromatography for the separation of plant photosynthesis, reactions in the on what is today Kirchgasse 9, is now of complex mixtures of carotenoids) stereo- earth’s atmosphere and technically im- occupied by the Theological Faculty of chemistry of carotene epoxides, synthesis portant processes in polymer production the University of Zurich. (O-, N-, S-heterocycles, optically active syn- and paint hardening, free radicals appear [2] Löwig discovered bromine somewhat thons for polyene synthesis, models for CD as short-lived intermediates. They are later but independently of Balard. studies), Biosynthesis of cyclic carotenes. molecular fragments with a free electron [3] Festschrift ‘Die Universität Zürich that is not part of a bond. Due to their spe- 1833− 1933 und ihreVorläufer’, E. Gagliardi, W. v. Philipsborn cific magnetic properties it is possible to H. Nabholz, J. Strohl, Zurich, 1938. Research into preparative, structural observe and identify these particles dur- [4] His books were carefully kept in the and physical aspects of organometallic ing the reaction using physico-chemical library of the Chemistry Institute as compounds. Emphasis on the application methods, and to determine the mechanism objects of great value. Löwig had taught before and for some time after his and development of high-resolution NMR and rate of reaction. Methods used include appointment as associate professor at methods to problems on the border between ESR, NMR, myon spin rotation and opti- the ‘Industry School’, a school of further organic and inorganic chemistry. Projects: cal spectroscopy, with modern computer education for the technical professions. Synthesis of single and multi-nuclear ole- technology to control the equipment and One of his students from Easter 1833 fin complexes, of transition metal clusters analyse the data. onwards was Gottfried Keller, whom he in the gas-phase; one and two-dimensional continued to act as mentor, for example NMR of organic compounds; use of 15N G. Wagnière in his recommendation to the Erziehungs- NMR on organic chemical structure prob- The natural and magnetic-field induced and Regierungsrat for the stipend in 1848. [5] lems and biochemical problems. optical activity of molecules are measured and interpreted with quantum mechanics. [5] E. Ermatinger, ‘Gottfried Kellers Leben’, Artemis, Zurich, 1950. M. Hesse The methods used include circular dichro- [6] Festschrift ‘75 Jahre chemischer For- At the centre of our research activities ism (CD), magnetic circular dichroism schung an der Universität Zürich’, pro- are investigations (isolation, structure anal- (MCD), circular polarised luminescence duced by chemistry students of the ysis) of natural products (particularly in- (CPL) and fluorescence detected circular University of Zurich, Zurich, 1909. dole-, spermidine-, and spermine alkaloids) dichroism (FDCD). The principle interest [7] Now the ‘Seminar for Pedagogic Studies and their relevance as chemotaxonomic in- is in organic molecules, particularly those Zürichberg Section’, Rämistrasse 59; in dicators, and the synthesis of macrocycles of biological significance. In addition theo- later years the ‘Alte Kantonsschule’ to (lactames, lactones, carbocycles) by means retical studies on the new magnetooptical differentiate from the new building on of ring expansion reactions of smaller car- and non-linear optical effects are under- Rämistrasse 74. bocycles (zip-reaction). taken. The aim is the application of modern [8] Löwig was honoured for his services to non-linear optics as a molecular spectros- chemistry in Zurich on the occasion of the centenary celebration of the University A. Vasella copy method. of Zurich (1933) by the Zurich Chemical Carbohydrates and their use as starting Society with a commemorative plaque in materials for the preparation of other natu- J. H. Huber the entrance hall of the chemistry building ral products (nucleosides, antibiotics, amino Research includes: molecular dynamics on Rämistrasse 76. acids, phosphone acid, enzyme inhibitors). (energy absorption, energy distribution, re- [9] Later improved and expanded by Prof. New methods for the asymmetric induction laxation), laser spectroscopy of molecules Abeljanz, it was used in lecture courses in connection with the anomeric effect. Nov- in molecular beams and in matrices, and up to the beginning of the 20th century. el nitrosugars are synthesised and used to in- investigations of light-induced chemical [10] From1911the‘EidgenössischeTechnische vestigate preparatively useful methods and processes. Hochschule’ (ETH). the production of rare sugars (amino sugars, [11] The shared Chair for Chemistry was neuraminic acids). Methods for glycoside K. Lendi retained until 1872; for other subjects synthesis and the synthesis of complex car- In the framework of a general theory of e.g. astronomy, geology, crystallography, mineralogy, palaeontology, pharmacology bohydrates have been initiated. irreversible processes, theoretical predic- double professorships (ETH and Uni- ationofneweffectsinpolyatomicmolecules versity) still exist today. H. Heimgartner are developed, such as quantum oscillation [12] Owned by the Canton of Zurich until Research interests include: mechanisms (beats) or magnetic resonance phenomena 1908; demolished when the Semper of thermal and photochemical reactions of in chemically reacting systems. building was extended, ca. 1910. 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 100 CHIMIA 2008, 62, No. 3

[13] Pompejus Bolley, fi rst professor for tendencies of his family and the proximity [32] Werner’s private assistants had the job of technical chemistry at the Polytechnic. to Mulhouse. verifying all the analyses of the doctoral [14] A vibrant picture of the situation in chem- [25] The Polytechnic received the Ius students. istry at that time is given in: R. Meyer, Promovendi in 1909. Werner’s dissertation [33] e.g. A, Hantsch (SS 1885− 1893), E. ‘Victor Meyer, Leben und Wirken eines was assessed by Abeljanz and Merz, who Bamberger (SS 1893− SS 1905), F. P. deutschen Chemikers und Naturforschers commented very positively on his work. Treadwell (WS 1893/94− 1918), G. Lunge 1848− 1897’, Akad. Verlagsges., Leipzig, His Klausurarbeit on ‘The Theory of (SS 1876− SS 1907), R. Gnehm (WS 1917. Aromatic Compounds’ was judged as 1894/95− WS 1904/05), R. Willstätter (WS [15] Wislicenus earned his living as a teacher ‘excellent’. Werner gained his doctorate at 1905/06− WS 1912/13), H. Staudinger for chemistry and mineralogy at the 23 with the words ‘with particular merit (WS 1912/13− SS 1926). Industrial School and from 1862 for for excellence’. [34] It should be remarked that most ofWerner’s chemistry at the Veterinary Medicine [26] Werner’s portrait was probably painted at PhD students came from abroad. Approx. School (founded in 1820, fi rst as a this time. It hung in the Director’s office 230 dissertations were completed under private institution and then as the state- at Rämistrasse 76. Little is known about Werner’s supervision. 46 students were run School for Veterinary Medicine; his work with Bertholot. It is possible Swiss (one woman), 179 were foreign 1902 taken into the University as the that many of the experiments that Werner (including 21 women); no nationality Faculty of Veterinary Medicine). demonstrated in his lectures in inorganic is given on some of the dissertations. In [16] The real reasons for the abrupt departure chemistry originate from his time as a addition the entrance requirements for of Wislicenus from Zurich are not easy student in Paris. His successor Karrer the University seemed to have been less to uncover. In 1861 Wislicenus had used the same experiments unchanged for strict that for the Polytechnic. Even today become a citizen of Zurich. His younger many years. the ETH has the reputation as the ‘Swiss’ brother Hugo, senior lecturer for German [27] See also [28, 29]. The appointment academic institution amongst high-school language and history (1863–1866) and a commission consisted of Profs A. students. Karrer[28] and Tiburtius[35] give teacher at the college in Küsnacht, died Kleiner (physics, chairman), H. Abeljanz lively descriptions of the international in an accident on the Tödi in 1866. The (chemistry), A. Heim (geology) and A. character at the time of Werner. gradual transformation from a persecuted Lang (zoology). Based on the expert [35] F. Tiburtius, ‘Erinnerungen einer Achtzig- free-church member to a prominent opinions of Prof. A. v. Baeyer, M. jährigen’, C. A. Schwetschke & Sohn, German nationalist is clearly described Berthelot, J. Wislicenus, Emil Fischer, Berlin, 1923. in the obituary by Beckmann.[17] During V. Meyer, A. Hantsch and R. Gnehm, [36] Offers came from an unknown univer- a celebration in Zurich of the victory of the following chemists were proposed sity in 1895, the University of Bern Germany over France, presided over by as possible candidates: Prof. Hans v. 1897, the University of Vienna 1900, the Wislicenus on 9.3.1871, a serious clash Pechmann (Munich), Prof. F. K. J. Thiele University of Basel 1902, Eidgenössisches with demonstrators supporting France (Munich) and Privatdozent Dr. A. Werner Polytechnikum 1905, the University of occurred which became known as the (Polytechnic). Werner was put on an equal Würzburg 1910, the University of Leipzig ‘Concert Hall Riot’. par with the 13-years older v. Pechmann 1911. [17] E. Beckmann, Obituary for J. Wislicenus, and before Thiele. The recommendations [37] Apparently Rämistrasse 59. Ber. Dtsch. Chem. Ges. 1904, 37, 4861. seem to be prophetic from today’s [38] After Chemistry moved out in summer and [18] A. Werner and O. Meister wrote a vibrant viewpoint! A visit by Kleiner and Heim to autumn 1978, the buildings Rämistrasse account of the life of Merz fi lled with one of Werner’s lectures and a presentation 74 and 76 were completely renovated; see personal experiences: A. Werner, O. to the Naturforschende Gesellschaft on Section 11. Meister, Verhand. Schweiz. Natur. Ges. 26.6.1893 impressed the Commission so [39] For the descriptions that were used for 1904, LX. much that they invited him to a formal this Section see [6, 28, 29, 34, 40− 44]. [19] In 1877 the same matter was discussed lecture before the Faculty. Kauffmann[29] is particularly informative again and Victor Meyer at the Polytechnic [28] P. Karrer, Obituary for A. Werner, Helv. since many documents were used that was asked to write an expert opinion. As Chim. Acta 1919, 3 , 196; P. Karrer, were not accessible earlier. the result of his recommendation, both Gesnerus (Zurich) 1966, 23, 273; P. [40] P. Pfeiffer, Obituary for Alfred Werner, professors were retained. Karrer, Helv. Chim. Acta Fasc. Extraord. Chemiker Zeitung 1913, 1517. [20] Merz lived initially in the ‘Kratz’ in un- 1967, 7. [41] E. Berl, ‘Some Personal Recollections of usual lodgings. His peculiar, old-fashioned [29] G. B. Kauffmann, ‘AlfredWerner, Founder Alfred Werner’, J. Chem. Educ. 1942, 19, clothing gave him an odd appearance. But of Coordination Chemistry’, Springer, 153. his generosity in fi nancial matters and his Berlin, 1966. [42] I. Lifschitz, ‘Alfred Werner’, Z. Elektro- helpfulness should be emphasised. He left [30] An unpleasant controversy developed chem. 1920, 26, 514. the University a valuable legacy. Several over time with Abeljanz on this point [43] J. Read, ‘Humour and Humanism in books in the library of the Chemical that is given detailed treatment in the Chemistry’, G. Bell & Sons, London, Institutes originate from his extensive and excellent biography by Kauffmann. 1947. well-ordered collection. [29] The situation damaged Werner’s [44] D. H. Wilcox Jr., ‘Werner and Dyes’, Adv. [21] Merz’ style of writing in his publications reputation internationally more than he Chem. Series 1966, 62, 86. is very dry. He presented the new results deserved. [45] The following text is based on refs briefly and usually without any relation to [31] Abeljanz’ services to teaching should [46− 51]. an existing wider context. not be underestimated; as Staub [46] A. Werner, ‘Lehrbuch der Stereochemie’, [22] V. Meyer, Obituary for W. Weith, Ber. commented:[23] “I had the honour as Gustav Fischer, Jena, 1904. Dtsch. Chem. Ges. 1882, 15, 3291. a young student to attend lectures by [47] A. Werner, ‘Neuere Anschauungen auf [23] M. Staub, ‘Das chemische Laboratorium this excellent lecturer”. Scientifically dem Gebiet der anorganischen Chemie’, des Kantons Zürich 1877− 1952’, Abeljanz did not achieve much. It is Vieweg & Sohn, Braunschweig, 1920. commemorative article for the 75th odd that much later Karrer held the [48] G. Schwarzenbach, ‘Alfred Werner and anniversary, Zurich, 1952. experimental lecture course in inorganic his Accomplishments’, Helv. Chim. [24] After the war in 1870/71 France lost chemistry up to his retirement (1959) Acta, Fasc. Extraord. 1967, 38; G. Alsace to Germany. Werner was called although a much better qualified lecturer Schwarzenbach, ‘Die Entwicklung up for military service on 1.10.1885. He in Schwarzenbach was available in der Valenzlehre und Alfred Werner’, still found the time to attend some lectures the same institute. A deal of the blame Experientia 1966, 22, 633. in chemistry at the technical university. for this misfortune resulted from the [49] F. Feigl, J. C. Bailar Jr., L. Horner, F. His choice of Zurich for his studies later unhappy connection of the professorial A. Cotton, C. Klixbüll Jörgensen, L. was probably due to the francophone salary and the Kollegiengelder. Malatesta, K. B. Yatsimirskii, D. H. 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 101 CHIMIA 2008, 62, No. 3

Busch, A. D. Wadsley, articles in Helv. [68] C. H. Eugster, Vierteljahresschrift der research: H. Kuhn, Obituary for Werner Chim. Acta, Fasc. Extraord . 1967. Naturf. Ges. Zürich 1971, 116, 506; C. Kuhn, Helv. Chim. Acta 1964, 47, 689. [50] ‘The Chemistry of the Coordination H. Eugster, Verhand. Schweiz. Naturf. [84] M. Kofl er, Obituary for Hans v. Halban, Compounds’, Ed. J. C. Bailar Jr., Reinhold, Ges. 1971, 253; C. H. Eugster, Chemie in Helv. Chim. Acta 1948, 31, 120. N.Y., 1956 with 23 review articles from unserer Zeit 1972, 6 , 147. [85] The full structure determination of the different authors. [69] A. Wettstein, Helv. Chim. Acta 1972, 55, photoproducts of ‘tetrabenzoyl-ethylene’ [51] ‘Werner Centennial’, Ed. R. F. Gould, 313. was carried out much later, see ref. [86]. Adv. Chem. Series 62, Amer. Chem. Soc. [70] O. Isler, Biograph. Mem. Fellows Royal [86] J. R. Cannon, V. A. Patrick, C. L. Raston, A. 1967 with 42 review articles from different Soc. 1978, 24, 244. H. White, Aust. J. Chem. 1978, 31, 1265. authors. [71] Karrer’s brother Walter (19.8.1891− 1961) [87] Obituary of K. Clusius and appreciation [52] G. N. Lewis, ‘Valence and the Structure obtained his doctorate in 1919 under of his scientific work: K. Schleich, Helv. of Atoms and Molecules’, The Chemical the supervision of Profs Werner and Chim. Acta 1964, 47, 234. Catalog Co., N.Y., 1923. Karrer on ‘Optically Inactive and Active [88] G. Wagnière, Obituary for Heinrich [53] A. Hantzsch,A. Werner, Ber. Dtsch. Chem. Diethylenediamine-Co-propionyl- Labhart, Helv. Chim Acta 1978, 61, 30. Ges. 1890, 23, 11, 1243, 2336, 2764. acetonato Salts’). [89] During the official inauguration ceremony, [54] Hantsch added the following postscript [72] Transcript of the Regierungsrat meeting the building was characterised somewhat to the fi rst article:[53] “In conclusion, the of 16.10.1919, RRB No. 2748. sarcastically as an ‘academic shunt yard’ undersigned fulfils a duty of care for the [73] Unfortunately neither the names of the by Regierungsrat president Dr. A. Gilgen. case that the above developments should referees nor their recommendations could [90] W. Schneider, Obituary for Gerold received some recognition, by giving be found. Schwarzenbach, Helv. Chim. Acta 1978, the following declaration: the theory [74] The situation was not easy for Karrer 61, 1949. published here in collaboration with Herr in another aspect. From the records it [91] Discovered by W. Biedermann, a coworker A. Werner is the intellectual property of is obvious that the Medical Faculty, at that time of Schwarzenbach, after he had Herr Werner…” during the procedure to appoint a searched through the very large collection [55] A. Werner, ‘Beitrag zur Konstitution successor to Werner and then again of organic dyes that still exists today, for anorganische Verbindungen’, Z. Anorg. during the reappointment of the associate suitable structures. Allg. Chem. 1893, 3 , 267. professorship previously awarded to [92] In 1967 Schumacher was appointed [56] An authentic description is given by King Karrer and again during the appointment professor at the University of Fribourg and in ref. [44]. of the successor toAbeljanz, exerted strong since 1972 holds the Chair for Inorganic [57] Complexes prepared by Werner’s doctoral pressure on the Philosophical Faculty II and Physical Chemistry at the University students and coworkers are today part of and the education authorities to be given of Bern. the ‘Werner Collection’ in the archives a vote in the appointment and the design [93] H.-J. Hansen, M. Hesse, W. v. Philipsborn, of the Chemistry Institutes. There are of the teaching and that they eventually Obituary for Hans Schmid, Helv. Chim. thousands of individual substances. applied for a Chair in Chemistry in the Acta 1978, 61, 1. [58] A. Werner, ‘Über die Konstitution und Medical Faculty (to the cost of a Chair in [94] Details associated with this appointment Konfiguration von Verbindungen höherer Phil Fac. II). Since they at the same time will not be stated here, for obvious Ordnung’, Helv. Chim. Acta, Fasc. demanded an extensive reduction in the reasons. Extraord. 1967, 24. botany, zoology and comparable anatomy [95] See the detailed description in ref. [93]. [59] The diagnosis was ‘progressive, content, the Philosophical Faculty II stood [96] The assessment of the results of the Zurich degenerative, general arteriosclerosis, in fi rmly behind Karrer. The circumspect research group by a competitor see: A. particular of the brain’. handling of the difficult discussions by R. Battersby, H. F. Hodson, Quart. Rev. [60] The resistance of Werner to his condition the Erziehungsdirektor Dr. Mousson is the Chem. Soc. London 1960, 14, 77. and his belief in a full recovery that is reason that chemistry was not forced into [97] When sufficiently large glass tubes for the obvious in every application for leave the role of a subsiduary subject. chromatography columns could not be were based on good reasons: Werner [75] Karrer’s character is described in [65, 68, found, a tube made of stainless steel was always experienced periods of completely 69]. The not altogether happy relationship obtained, bored and polished to give the clear thinking. Witness to this is a letter with Ruzicka in later years will not be exact calibre by a Zurich weapons factory. dated 28.1.1918 to the Philosophical described here. [98] Karrer had long suspected that the Faculty II in which he expresses his [76] P. Karrer, Obituary for Prof. Ernst B. H. calebasse alkaloids belonged to the opinion thoroughly and far-sightedly Waser, Helv. Chim. Acta 1941, 24, 852. strychnine class. In 1948 he proposed a over twelve pages on the subject of the [77] P. Karrer, Obituary for Carl Naegeli, chemical and pharmacological study of successor to Prof. Pfeiffer. He must have Helv. Chim. Acta 1943, 26, 730; quaternary strychnine salts. suffered greatly when he fi nally realised Vierteljahresschrift der Naturf. Ges. [99] The legislative planning work that preceded the seriousness of his condition. Zürich 1942, 87, 525. the partial relocation of the University can- [61] See in this connection the description in [78] Further candidates under discussion were: not be described here for reasons of space, ref. [74] Prof. Kaufmann, Geneva, Dr. Baragiola, see ref. [100]. It is also not possible to de- [62] The lecturers denoted with an asterisk Zurich, Dr. Ruggli, Basel, Dr. Gränacher, scribe the sometimes vehement agitation had done their habilitations both at the Dr. Waser, Dr. Ruzicka, all from Zurich. by influential student politicians against University and ETH. [79] The archives contain letters from Profs. the Irchel project. But it should be empha- [63] The transcript of the Regierungsrat (meet- P. A. Guye, Geneva and A. I. Bernoulli, sised that the Student Chemical Society ing on 20.7.1916, RRB No. 1769) shows Basel. expressed clear support for the project. that the Erziehungsdirektion and the [80] Further opinions were probably obtained. [100] ‘Universität Zürich-Irchel, 1. Etappe’, University Commission tried unsuccess- The archives also contain an unfavourable document from the Department of Public fully to persuade Pfeiffer to change his reference from Albert Einstein, Berlin on Buildings and the Department of Education mind. Bernoulli (20.12.1919). of the Canton of Zurich, July, 1979. [64] R. Wizinger wrote a short obituary for [81] Rooms in Rämistrasse 76; laboratory [101] Transfer of room capacity from Chemistry Pfeiffer: R. Wizinger, Helv. Chim. Acta courses in Room 17, PhD students in to Zoology. 1953, 36, 2032. rooms 9, 12, 14, 15. [102] Today this includes the following [65] P. Pfeiffer, ‘Organische Molekülverbin- [82] H. v. Halban, Obituary for Victor Henri, Institutes: Inorganic, Organic, Physical dungen’, Enke, Stuttgart, 1922. Vierteljahresschrift der Naturf. Ges. Chemistry, Zoology, Zoological Museum [66] Transcript of the Regierungsrat meeting Zürich 1941, 86, 308. (scientific part), IT (user centre), and of 28.2.1918, RRB No. 508. [83] Obituary of Werner Kuhn and appreciation facility management. All fi rst year [67] Biographies of P. Karrer, see refs [68− 70]. of his most significant and versatile students in the sciences and medicine 175th ANNIVERSARY OF THE UNIVERSITY OF ZURICH 102 CHIMIA 2008, 62, No. 3

attend lectures, tutorials and practical [105] The large number of diploma theses are courses in these buildings. not discussed here, although many exceed [103] P. Karrer, ‘Zürich als Stätte chemischer the range of many earlier dissertations Forschung in den letzten 100 Jahren’, because the diploma students, with a few. in ‘Festschrift zur 200-Jahr-Feier der exceptions, went on to start a dissertation Naturforschenden Gesellschaft in Zurich’, [106] In the travelling exhibition that the 1946, p. 178. University made to celebrate its 150th [104] It is not possible to give exact fi gures anniversary, the Chemistry Institutes because in the early years many external produced a slide show of the many dissertations ( e.g. from the Polytechnic and diverse professions that the former until 1909) were submitted to the doctorates of chemistry have moved into. University for a doctorate. When the [107] The senior lecturers and the titular external place of research is obvious from professors H. Streuli and K. Bernauer the dissertations, they were not included in are employed in industry and do not have our records. However, those dissertations research groups at the Institute of Organic that were prepared at the University but Chemistry. the doctorate awarded elsewhere are also not counted.