Conformational Dynamics and Strain Johannes Wislicenus 1835-1902

Total Page：16

File Type：pdf, Size：1020Kb

Conformational dynamics and strain Johannes Wislicenus 1835-1902 "specially directed forces, the affinity-energies” are responsible for torsional motions in a molecule (vibrational, rotational, angular …) Need not think about molecules as static in 2D! Ring strain … aka angle strain … aka Baeyer strain Adolf von Baeyer (1853-1917) Recognized the strain that must be present in small rings Dye synthesis Nobel Prize 1905 Pics: Wikipedia Cyclohexane as a chair? Herman Sachse 1890 Realized cyclohexane need not be planar, Conformational isomers would alleviate strain! (At left, Hernán Sachse) Zeitschrift für physicalische chemie, 10, 201-241 (1892) Sachse’s problem: Organic chemists don’t math so good. Cyclohexane as a chair? 1918: structural proof for the “chair” … diamond! Odd Hassel (1897-1981) Determined cyclohexane structure and fluxionality Published in Norwegian Sir Derek Barton (1918-1998) Conformational Analysis He read the Scandinavian lit! Shared the 1969 Nobel Prize Pics: Wikipedia Fused rings – decalin system: cortisone Thank you Google image search Stereoisomerism proposals 1874 Joseph Achille Le Bel Jacobus Henricus van’t Hoff 1847-1930 1852-1911 (France) (The Netherlands) “La chimie dans l’espace” First Nobel Prize Pics: Wikipedia Manuscript reviews: ca. 1874 "A Dr. J. H. van ’t Hoff of the Veterinary School at Utrecht has no liking, apparently, for exact chemical investigation. He has considered it more convenient to mount Pegasus (apparently borrowed from the Veterinary School) and to proclaim in his ‘La chimie dans l’espace’ how, in his bold flight to the top of the chemical Parnassus, the atoms appeared to him to be arranged in cosmic space." Hermann Kolbe, senior editor of the Journal für Praktische Chemie Chiral discrimination Jones, Organic Chemistry 2nd ed. Fig. 4.26 Importance of chirality Smell: R-carvone: S-carvone: spearmint caraway Toxicity of a morning sickness drug: Harmless to fetus Teratogen: limb defects “Therapeutics:” Vick’s inhaler meth Cahn-Ingold-Prelog 1950-1955 Robert Sidney Cahn Sir Christopher K. Ingold Vladimir Prelog 1899-1981 1893-1970 1906-1998 (R-S naming from R.S.?) Reaction mechanisms Nobel Prize 1975 Pics: Wikipedia.

Copy Link

Recommended publications

Interview with Linus Pauling
LINUS PAULING (1901-1994) INTERVIEWED BY JOHN L. GREENBERG May 10, 1984 Photo by M. Opalenik c. 1964 ARCHIVES CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California Subject area Chemistry Abstract Interview in 1984 with Linus Pauling, professor of chemistry emeritus. He recalls his instructorship in quantitative analysis at Oregon Agricultural College at age 18. To Caltech for graduate study, 1922. As preparation, Arthur Amos Noyes sent him proof sheets of Noyes’s new book, Chemical Principles. Studied X-ray crystallography with Roscoe G. Dickinson. Gave seminar on Debye-Hückel theory of electrolytic solutions for visiting P. J. W. Debye. Recollections of Noyes (then chairman of the Division of Chemistry and Chemical Engineering), Dickinson, and Ralph W. G. Wyckoff. Discusses X-ray crystallography and its history. Recollections of Gilbert N. Lewis, Caltech’s rivalry with Berkeley. Paper with Richard C. Tolman on residual entropy of crystals; recalls courses with Tolman. Offer of professorship at Harvard in 1929 and MIT c. 1930. Death of Noyes (1936) and Pauling’s appointment as chairman of chemistry division (1937). Remarks on Biology Division and advent of Thomas Hunt Morgan (1928). Work on hemoglobin in mid-1930s. Remarks on Karl Landsteiner and immunology. Lectures on “complementariness” as basis of biological specificity; paper with Max Delbrück. Projected book on the molecular basis of biological specificity, to be called The Nature of Life. Recollections of Albert Tyler and http://resolver.caltech.edu/CaltechOH:OH_Pauling_L George W. Beadle. Comments on relations with Warren Weaver and Rockefeller Foundation. Discusses work on protein structure and discovery of alpha helix. Discusses his reasons for leaving Caltech in 1963 and the attitude of Caltech president Lee DuBridge and John Roberts, then chair of the chemistry division.
[Show full text]
Early Russian Organic Chemists and Their Legacy
SpringerBriefs in Molecular Science Early Russian Organic Chemists and Their Legacy Bearbeitet von David Lewis 1. Auflage 2012. Taschenbuch. xii, 136 S. Paperback ISBN 978 3 642 28218 8 Format (B x L): 15,5 x 23,5 cm Gewicht: 237 g Weitere Fachgebiete > Chemie, Biowissenschaften, Agrarwissenschaften > Chemie Allgemein > Geschichte der Chemie Zu Inhaltsverzeichnis schnell und portofrei erhältlich bei Die Online-Fachbuchhandlung beck-shop.de ist spezialisiert auf Fachbücher, insbesondere Recht, Steuern und Wirtschaft. Im Sortiment finden Sie alle Medien (Bücher, Zeitschriften, CDs, eBooks, etc.) aller Verlage. Ergänzt wird das Programm durch Services wie Neuerscheinungsdienst oder Zusammenstellungen von Büchern zu Sonderpreisen. Der Shop führt mehr als 8 Millionen Produkte. Chapter 2 Beginnings 2.1 Introduction At the start of the twentieth century, organic chemistry was not yet 75 years old as a separate and legitimate sub-discipline of the science. Considerable progress had been made in these first seven decades, and the stage was set for the dramatic advances in the science to come in the following century. Most practicing organic chemists are familiar with many of the great German, French and English organic chemists whose work helped the fledgling discipline grow, but few are familiar with the role that Russian organic chemists of the nineteenth and early twentieth century played in the development of the science. And this is in spite of the fact that many of the named rules and reactions that one studies in the first course in organic chemistry are, in fact, of Russian origin. It is the intent of this book to help rectify that deficiency.
[Show full text]
SCIENCE HISTORY INSTITUTE ISABELLA KARLE and JEROME
SCIENCE HISTORY INSTITUTE ISABELLA KARLE and JEROME KARLE Transcript of an Interview Conducted by James J. Bohning and David K. Van Keuren at Naval Research Laboratory Washington, District of Columbia on 26 February, 15 June and 9 September 1987 (With Subsequent Corrections and Additions) Upon Isabella Karle’s death in 2017, this oral history was designated Free Access. Please note: This oral history is protected by U.S. copyright law and shall not be reproduced or disseminated in any way without the express permission of the Science History Institute. Users citing this interview for purposes of publication are obliged under the terms of the Center for Oral History, Science History Institute, to credit the Science History Institute using the format below: Isabella Karle and Jerome Karle, interview by James J. Bohning and David K. Van Keuren at Naval Research Laboratory, Washington, District of Columbia, 26 February, 15 June and 9 September 1987 (Philadelphia: Science History Institute, Oral History Transcript # 0066). Formed by the merger of the Chemical Heritage Foundation and the Life Sciences Foundation, the Science History Institute collects and shares the stories of innovators and of discoveries that shape our lives. We preserve and interpret the history of chemistry, chemical engineering, and the life sciences. Headquartered in Philadelphia, with offices in California and Europe, the Institute houses an archive and a library for historians and researchers, a fellowship program for visiting scholars from around the globe, a community of researchers who examine historical and contemporary issues, and an acclaimed museum that is free and open to the public. For more information visit sciencehistory.org.
[Show full text]
Chemistry Is All Around Us
Chemistry is all around us. Everyone can and should understand basic chemistry. The Story Apart from those wanting to become chemists, students Central wanting to become doctors, nurses, physicists, Science Cover nutritionists, geologists, and pharmacists all need to study chemistry. It is important to remember that the Chemistry importance of chemistry would not be diminished BIMAN BASU over time; rather it will continue to remain a That is not all. There would be no drugs a science. It was primarily directed at efforts promising career prospect. – painkillers, antacids, or antibiotics – no to turn all kinds of substances into the polyester fibre or nylon stockings, no precious metal gold by early chemists, who stainless steel, no sugar-free soft drinks, were known as alchemists. We have heard IGHT from the moment we get up in even no Diwali illumination and fireworks about the “philosopher’s stone” using which the morning till we go to bed at without chemistry. Without chemistry, we the alchemists sought to turn any metal night, we come intimately close to R would not have such items as computers, into gold. Of course it was a silly thought, chemistry and things related to it. The CDs, DVDs, iPods, fuel for vehicles, oil to because no one can really turn one toothpaste we use to clean our teeth, the cook, refrigeration units, radios, televisions, element into another by mere touch! Still, toilet soap, shampoo, and plastic buckets batteries, and so much more. So, then, the alchemists made important we use to take bath, the plastic comb
[Show full text]
Obituary. Sir Edward Frankland
OBITUARY. SIR EDWARDFRANKLAND. E are again called upon to note the departure of a CO- W worker and master in our chosen field of science. Eulogy is not necessary. The good he has achieved lives after him, and we would merely note that the researches of Sir Edward Frankland. extending over a period of thirty years, relate to work in pure, applied, and physical chemistry. Those in pure chemistry were conducted at first in the laboratories of Playfair, Bunsen, and Liebig. They include subjects related to each other as follows : the conversion of the cyanogen group into the carboxyl group ; the change of the alkyl cyanides to the corresponding organic acids, the saponification of ethyl cyanide was announced by Edward Frankland and Hermann Kolbe when they were fellow assistants in Playfair’s laboratory in 1845. Although this reaction was not then pursued beyond the mono- basic acids, others applied it successfully in other directions. Then followed the action of metallic potassium upon ethyl cyanide and the polymerization of the latter, the isolation of the organic radicals, and the discovery of the organo-metallic com- pounds. Of these, which were investigated by Frankland throughout his scientific career, were zinc methyl and zinc ethyl, in. the study of which the author remarks: “ I had not pro- ceeded far in the investigation of these compounds before the facts brought to light began to impress upon me the existence of a fixity in the maximum combining value or capacity of saturation in the metallic elements which had never before been suspected.” The ready introduction of negative chlorine into bodies for a more electropositive constituent is a fact to which we give little thought.
[Show full text]
A TRANSNATIONAL NETWORK of CHEMICAL KNOWLEDGE: the PREPARADORES at the LISBON POLYTECHNIC SCHOOL in the 1860S and 1870S
26 Bull. Hist. Chem., VOLUME 39, Number 1 (2014) A TRANSNATIONAL NETWORK OF CHEMICAL KNOWLEDGE: THE PREPARADORES AT THE LISBON POLYTECHNIC SCHOOL IN THE 1860s AND 1870s Bernardo Jerosch Herold, Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, PT-1049-001 Lisboa, Portugal, [email protected] and Wolfram Bayer, Institut für Corpuslinguistik und Texttechnologie, Österreichische Akademie der Wissenschaften, Sonnenfelsgasse 19/8, A-1010 Vienna, Austria, [email protected] Antonio Augusto de Aguiar (1838-1887) was the graduated. Another co-author was Alexander Georg main author of the most important research in organic Bayer (1849-1928) of Bielitz in former Austrian Silesia, chemistry carried out in Portugal during the 19th century. who arrived in Lisbon four years after Lautemann, and Despite not attending any research school in Germany, has until recently evaded almost completely the attention France or Great Britain, Aguiar’s most important research of chemistry historians, in spite of his interesting profes- papers, on work carried out at the Chemical Laboratory sional career, patronized by his elder and more famous of the Lisbon Polytechnic School, were published in brother, Karl Joseph Bayer (1847-1904). The Lisbon Berichte der deutschen chemischen Gesellschaft between Polytechnic School employed Lautemann in 1864-65 and 1870 and 1874. Alexander Bayer from 1868 to 1872 as demonstrators in chemistry (preparadores), but between 1864 and 1876, How then did he acquire the knowledge, the in- three other chemists trained in Germany also worked spiration, and the experimental skills necessary for his as demonstrators at the Lisbon Polytechnic. Bayer and the other three chemists had in common that they were Vicente Lourenço (1822-1893), an élève of Adolphe recruited from the teaching laboratory of Carl Remigius Fresenius (1818-1897) in Wiesbaden.
[Show full text]
On Kekulé's Insight
On Kekulé’s insight Giuseppe Iurato E-mail: [email protected] Abstract. In this paper, we would like to retake a historical controversy on the alleged discovery of Kekulé’s Benzene structure formula from other possible epistemological viewpoints which might perhaps put into a more right historical perspective this apparent and unmotivated riddle, also with the aid of some elementary psychoanalytic considerations. Moreover, one of the purposes of this paper is also that of understanding some possible, general aspects underlying a creative process. 1. Introduction This paper is centered on the vexata quæstio concerning the so-called Kekulé’s insight, namely, the alleged question inherent the discovery of the Benzene structure1. The Benzene, as chemical substance, was isolated by Michael Faraday in 1825 and the qualitative chemical analysis detected only carbon and hydrogen in it, so that its empirical formula is CH. Subsequent repeated analyses and molecular weight determinations2 (mainly made by Eilhard Mitscherlich in 1834) have determined to be C6H6 its molecular formula. The chemical properties of this substance show a high unsaturation degree (due to its low hydrogen-carbon ratio equal to 1:1) but it is no subject to those typical chemical reactions which characterize the other already known organic compounds, whence it follows that such a substance did should fall into another, new class of organic compounds: indeed, it will be the simplest chemical substance of the so-called aromatic compounds class. Thereafter, one of the main theoretical task was to determine, according to the new Dalton’s atomic theory, the possible geometrical configurations related to the disposition of the carbon and hydrogen atoms.
[Show full text]
The Pursuit of Accurate Measurements: Gas Electron Diffraction from the 1930S to the 1960S
International Workshop on the History of Chemistry 2015 Tokyo The Pursuit of Accurate Measurements: Gas Electron Diffraction from the 1930s to the 1960s Mari Yamaguchi The University of Tokyo, Japan Introduction Most scientific instruments and experimental methods have been improved continually since their invention. Such improved methods sometimes change scientific practices and usually enable more accurate measurements that replace existing data with new ones. In his book, An Introduction to Scientific Research, the American chemist, E. Bright Wilson wrote the following about measurements at higher accuracy. Sometimes measurements at higher accuracy bring to light new and unforeseen discrepancies of fundamental importance. An example of this is the Lamb-Retherford measurements of hyperfine structure of hydrogen spectrum, which showed that the Dirac theory needed modification.1 This example showed the interrelationship between the theory and the measurement. The question this raises is: if there are discrepancies between the results of two measurement methods, does this render one of them obsolete or changed? To answer this question, I look to the case of the determination of molecular structures in the gas phase. Gas-phase molecules are less influenced by the environment than in the solid and liquid phase, and gas molecular structural studies have thus provided much fundamental information about molecular structures. In the 1960s, the methods for investigating gas molecules were gas electron diffraction and spectroscopy. In this paper,
[Show full text]
The 50Th Anniversary of How an Odd Hassle Became the Noble Subject of Physical Chemistry
"Boats or Chairs?" The 50th Anniversary of How an Odd Hassle Became the Noble Subject of Physical Chemistry Av Prof. Richard Engh, UiT torsdag 31. oktober kl.1415 Realfagsbygget, Storeaud (B302) UiT Norges arktiske universitet Fifty years ago, the 1969 Nobel Prize in Chemistry was awarded jointly to the Englishman Derek Barton and the Norwegian Odd Hassel “for their contributions to the development of the concept of conformation and its application in chemistry”. By the 1920s, it was known that molecules were defined not only by their atomic composition, but by the conformations allowed by the bonds between atoms. Rigid double bonds and stereochemistry distinguished molecules, but the seemingly free rotation of single bonds generated questions. Among them was the one now covered in introductory chemistry courses: what is the shape of the six-carbon ring of cyclohexane? Is it a boat, a chair, or something else? Odd Hassel, born in Kristiania in 1897, had studied chemistry in Oslo (Cand. Real. 1920), Munich, and Berlin (Dr. Phil. 1924), and returned to Norway and chaired the first department of physical chemistry. But just as he was making key discoveries, he was arrested in 1943 by the Nasjonal Samling and held as prisoner until late 1944. Only after the war could the research continue, and he published two key papers in 1947, in the first volume of Acta Chemica Scandinavica, that formed the basis of the Nobel prize. This talk will review some of these most interesting aspects of the life and research of Odd Hassel. Norsk kjemisk selskap avd. Nord-Norge ønsker alle velkommen .
[Show full text]
PDF Download
SynformPeople, Trends and Views in Chemical Synthesis 2019/11 Sulfonyl Fluoride Synthesis through Electro- chemical Oxidative Coupling of Thiols and Potassium Fluoride Highlighted article by G. Laudadio, A. de A. Bartolomeu, L. M. H. M. Verwijlen, Y. Cao, K. T. de Oliveira, T. Noël This document was downloaded for personal use only. Unauthorized distribution is strictly prohibited. Contact Your opinion about Synform is welcome, please correspond if you like: [email protected] Thieme A163 Synform Dear Readers, This new issue of SYNFORM could not be further In this issue from the grey and dull atmosphere of November! It is actually quite glittering and thoroughly enjoyable, Literature Coverage Catalytic Asymmetric Total Syntheses of (–)-Morphine besides being informative. The first article deals with a and (–)-Codeine .............................................A164 classic of organic chemistry, namely the total synthesis of (–)-morphine and (–)-codeine, but in this case it is Young Career Focus Young Career Focus: Dr. Ori Gidron a catalytic stereoselective version developed by (The Hebrew University of Jerusalem, Israel) ..........A169 Y.-Q. Tu (P. R. of China). The second article is a Young Career Focus interview with O. Gidron (Israel) who Name Reaction Bio Reaction Regiochemistry – Markovnikov, Zaitsev and describes his research and aims. The third article – Hofmann. .A172 a Name Reaction Bio – is a truly amazing and thorough report on a crucial chapter in the history of organic Literature Coverage Sulfonyl Fluoride Synthesis through Electrochemical chemistry: the Markovnikov and Hofmann rules and the Oxidative Coupling of Thiols and Potassium role of the trailblazers who made and rationalized those Fluoride .......................................................A180 textbook discoveries on the addition and elimination Coming soon .................................................A183 reactions, and their regiochemistry.
[Show full text]
Study Guide Sample Questions Molecules That Changed the World
Study Guide Sample Questions Molecules That Changed the World K. C. Nicolaou and Tamsyn Montagnon Wiley-VCH, 2008 Chapter 1: Introduction: Atoms, Molecules & Synthesis 1. Give a brief description (25 words or less) of the following terms: a) The Big Bang Theory b) The Atomic Theory of Matter c) The Periodic Table d) Deoxyribo nucleic acid e) Ribo nucleic acid f) Protein g) Secondary metabolite h) Chemical synthesis 2. Identify the scientific contributions of the following philosophers–scientists (10 words or less): a) Demokritos b) Dmitri Ivanovich Mendeleev c) John Dalton d) Aristotle 3. Give the names and symbols of four elements and four molecular structures essential for life on Earth (including stereochemistry when appropriate): 4. Give the names of 8 natural products and name the three main categories of living systems from which such natural products are isolated. 5. Name the milestone event in 1828 that symbolizes the birth of organic synthesis. 6. The impact of chemical synthesis on modern society has greatly enhanced the lives of people. Give five examples of such contributions: 7. Name three methods used today in the structural elucidation of organic molecules. Chapter 2: Urea & Acetic Acid 1. Describe the following terms (50 words or less): a) Vitalism b) Synthetic organic chemistry (or chemical synthesis, or organic synthesis) 2. Draw the structures of urea and acetic acid. In addition, name the chemists who first synthesized them in the laboratory and articulate the significance of each accomplishment. (10 words or less) 3. Name the countries in which the following eminent chemists worked and made their most important contributions in chemistry.
[Show full text]
The Royal Society of Chemistry Presidents 1841 T0 2021
The Presidents of the Chemical Society & Royal Society of Chemistry (1841–2024) Contents Introduction 04 Chemical Society Presidents (1841–1980) 07 Royal Society of Chemistry Presidents (1980–2024) 34 Researching Past Presidents 45 Presidents by Date 47 Cover images (left to right): Professor Thomas Graham; Sir Ewart Ray Herbert Jones; Professor Lesley Yellowlees; The President’s Badge of Office Introduction On Tuesday 23 February 1841, a meeting was convened by Robert Warington that resolved to form a society of members interested in the advancement of chemistry. On 30 March, the 77 men who’d already leant their support met at what would be the Chemical Society’s first official meeting; at that meeting, Thomas Graham was unanimously elected to be the Society’s first president. The other main decision made at the 30 March meeting was on the system by which the Chemical Society would be organised: “That the ordinary members shall elect out of their own body, by ballot, a President, four Vice-Presidents, a Treasurer, two Secretaries, and a Council of twelve, four of Introduction whom may be non-resident, by whom the business of the Society shall be conducted.” At the first Annual General Meeting the following year, in March 1842, the Bye Laws were formally enshrined, and the ‘Duty of the President’ was stated: “To preside at all Meetings of the Society and Council. To take the Chair at all ordinary Meetings of the Society, at eight o’clock precisely, and to regulate the order of the proceedings. A Member shall not be eligible as President of the Society for more than two years in succession, but shall be re-eligible after the lapse of one year.” Little has changed in the way presidents are elected; they still have to be a member of the Society and are elected by other members.
[Show full text]