HISTORY 142 CHIMIA 2006, 60, No. 3 Chimia 60 (2006) 142–148 © Schweizerische Chemische Gesellschaft ISSN 0009–4293 Recollecting the Institute of Organic Chemistry, ETH Zürich, 1972–1990 Claude E. Wintner* Jakob Schreiber In Memoriam Abstract: The author recalls several visits to the Institute of Organic Chemistry, ETH Zürich. The faculty and staff of the Institute are remembered. Some circumstances surrounding the history of the publication of the total synthesis of vitamin B12 are mentioned. Keywords: Institute of Organic Chemistry, ETH Zürich · Vitamin B12, total synthesis, publication I believe I first became aware of the Ins- went on to the pioneering efforts toward Pennsylvania, which would be my home titute of Organic Chemistry (Laboratorium vitamin B12. Without being unduly humble base for the next 30 years, I finally was able für Organische Chemie) of the ETH Zürich about the accomplishments of American to arrange a sabbatical year with Eschenmo- only in 1959, when I was a first-year gradu- chemistry, I nevertheless can say with truth ser at the ETH. Two further sabbaticals, in ate student in the Department of Chemist- that in general the Swiss chemists of that 1976–1977 and 1989–1990, followed; and ry at Harvard University. I was working time possessed a technical mastery (from it is of these stays in Zürich that I now remi- in the research group of the man who was the Praktikum, or related academic structu- nisce. I believe that in 1972 in some sense almost universally considered the foremost res, quite apart from more experience) that I just may have caught the Institute and the organic chemist of that time, Professor Ro- we Americans indubitably lacked, and in city – indeed, the entire country – engaged bert Burns Woodward. At the postdoctoral this respect nearly all of them helped me at in a way of life in some respects largely un- level the Harvard department in general, one time or another. altered since sometime prior to the World and Woodward’s group in particular, were Early in my time at Harvard, then, I heard Wars; and so I will endeavor to sketch this very international in character. The Wood- of Albert Eschenmoser, the young chemist period in time just before dramatic shifts, ward Group had a large Swiss contingent, at the ETH who had just bested our revered already then clearly in the offing, would many of whose doctorates were from the boss in a friendly race to the finish line of lead to major transformations. ETH, and these coworkers were prominent the total synthesis of the complex alkaloid Change seems to move from West to among those who had spearheaded the total colchicine. Clearly, this was someone to East. In America so much begins in Cali- synthesis of chlorophyll (completed around be reckoned with! Not long thereafter I at- fornia, and moves eastward (if initially the time I joined the group) and who then tended Eschenmoser’s series of lectures at frequently jumping over the great midsec- MIT, on colchicine and related topics, and tion of the country). In the same way, much from then on the idea formed in my mind change – and, sadly, the bad with the good that I must sometime study and work at the – has come from America to Europe, if with ETH, quite generally acknowledged at that the delay of a decade or two. Switzerland time to stand with Harvard at the pinnacle in 1972 still retained many of its old ways, of the discipline of organic chemistry – and not least because it had not suffered physi- most particularly with the man who in the cal damage during the wars. Thus, Zürich field of natural products synthesis already as I and my family experienced it when we was Woodward’s greatest rival and who arrived in 1972 still was in many respects soon was to join with him in a collabora- – and even architecturally – a European city tion of equals to complete the total syn- of the early part of the century, and it was of thesis of vitamin B12, upon which both al- special significance to me that from it I was ready had embarked separately. This dream able to make a palpable extrapolation to the gained further definition when I interacted lives of my parents, who had grown up in with Vladimir Prelog, the Chairman of the prewar Leipzig and Budapest before com- Institute, while he held a six-week visit- ing to America in 1930. I think the same *Correspondence: Prof. Dr. C.E. Wintner ing lectureship at Yale University, where I was true of academic life as I experienced Department of Chemistry was a faculty member from 1963 through it at the ETH of that time. In the course of Haverford College Haverford, PA 19041 USA 1968. In 1972–1973, after I had moved to the year 1972–1973 I came to realize, in [email protected] the professorship at Haverford College, in ways I could not have before, how I was an HISTORY 143 CHIMIA 2006, 60, No. 3 American, and how American I was. At the same time I came to a better sense of how European in my perspective I also was, as a result of my background, and these Europe- an views became reinforced. In 1976–1977, at the time of our second stay in Zürich, the city – and also its academic life – already had begun to change profoundly. By 1989– 1990, my final year of residence in the city, an entire set of alterations had become ir- reversible. No value judgment is intended – only again the sense that I am chronicling a largely bygone era. At that time the entire ETH was located primarily in the Universitätsstrasse quarter (Photos 1 and 2). From the very first I was welcomed generously, above all by Albert Photo 1. Entrance to the ‘Altbau’ of the Chemistry Department Eschenmoser and Vladimir Prelog, but as well by a host of others. In 1972 the new chemistry tower at Universitätsstrasse 16 was just in the midst of construction, so dergraduate and graduate training at the that the teaching laboratories of the Insti- ETH. His brilliance was soon recognized, tute for Organic Chemistry, and in addition and his uncovering of the relationships that a few of its research laboratories, still were ultimately would blossom into the biogene- housed in the historic old, original building, tic isoprene rule, building upon Ruzicka’s the ‘Altbau’, shared with the inorganic and great work in this area, but reaching well physical institutes. However, most of the re- beyond it, had brought him to the attention search activity in organic took place in the of the chemical world early in his career. ‘Neubau’, the post-World War II structure Given the benefit of hindsight I now real- at Universitätsstrasse 8 built especially for ize that, just at the time of my arrival in the organic chemists under the leadership Zürich, Eschenmoser faced an interesting of the great Leopold Ruzicka (Ruzicka still and critical juncture in his career. The im- came to the labs to visit off and on in 1972, mense collaborative effort of the total syn- although by then he no longer was very ac- thesis of vitamin B12 had been completed in tive; I only met him briefly on a couple of February of 1972, and while there remained occasions). I was assigned one of the six some important matters to be worked out, desks in a long, rather narrow room near it seemed evident that Eschenmoser was at the old library in the Altbau. Three desks the same time searching for a new domain were held by ETH-Privatdozenten, and of research. It now is clear that I was pres- three by visitors. By some standards this ent at a pivotal moment: the end of Eschen- arrangement might have been considered moser’s efforts in the area of high-profile lacking in privacy, but in fact it provided organic natural products synthesis and the for an extremely stimulating atmosphere. beginning of his exploration of the self-as- We all respected long periods of relative sembly of the molecules of life, the project quiet (and, as I remember, there was only a that has occupied him ever since. One could single telephone, which we were careful to Photo 2. Chemistry Buildings on Universitäts- say that, having in the 1950’s considered strasse use only for quick incoming messages). At the question: How are the molecules of Na- the same time, scientific interactions were ture (at least, the isoprenoids) assembled? natural. Hans-Beat Bürgi occupied the ad- real productivity, than I believe is appreci- – and then digressed a while to answer the joining desk, and as the year progressed I ated, or at least properly acted upon, in the question: Am I able to assemble Nature’s witnessed at first hand the development of design of modern laboratories. During my molecules? (Yes!) – he advanced to ques- the ideas now summed up in the concept second visit, just four years later, the splen- tions that are considerably more profound: of the Bürgi-Dunitz trajectory for nucleo- did new tower was complete. Each member How did the molecules of Nature become philic chemical reactions at a carbonyl of the Institute had his own floor. I had my assembled in the first place? Why those par- function. own private office. I do not wish to imply ticular molecules? However, to emphasize As a result of crowding, all the groups that this second visit was not a success in all the point once again, little of this was appar- of the Institute worked on top of one an- respects, intellectually and otherwise – for, ent to me in 1972; I simply was visiting in other, so to speak, the consequence being as will be seen below, quite the contrary the research group of one of the few organic an environment with a great deal of intel- certainly was true – but it was undeniable chemists in the world – indeed, perhaps the lectual cross fertilization.