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Proceedings of the Chemical Society. March 1964 |
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Proceedings of the Chemical Society ,
Volume 1,
Issue March,
1964,
Page 73-100
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PROCEEDINGS OF THE CHEMICAL SOCIETY MARCH 1964 THE STEACIE MEMORIAL LECTURE* By HARRYE. GUNNING WITHINthis century we have seen bewilderingly rapid The thirty-five years of his career as a free-radical changes in the role of fundamental scientific research kineticist began in the late twenties at which time a in our society. What was formerly an inexpensive few of the more imaginative kineticists were begin- academic pursuit has now become the pride of ning to suspect that free radicals played some role nations and an enormously costly undertaking which in certain chemical processes. Today largely through taxes national budgets influences political opinion his own enormous contributions to the field and the and determines to a significant extent the relative contributions of those who were either trained in his importance of nations in the international com-laboratory or influenced by his work free-radical munity.Today science and government are inex- chemistry is one of the most important areas of tricably linked by the strong bond of mutual modern physical science. dependence and modern scientists must concern Edgar William Richard Steacie was born on themselves not only with the complex problems of their own fields of research interest but in addition Christmas Day 1900 in Westmount Quebec. After they must assume the heavy responsibility of repre- graduating with distinction in Chemical Engineering senting to a lay government the needs and objectives at McGill in 1923 he joined the graduate school in of science itself.The man whose memory we honour physical chemistry at that institution. Here he came in this lecture was at once a research scientist of the under the inspired leadership of Professor Otto highest stature and at the same time an eminent Maass who inculcated in him a deep devotion to scientist-statesman who is responsible in a large fundamental research and the academic life in measure for the recent growth of scientific activity in general. Throughout his brilliant career Steacie Canada both in the universities as well as in always championed the cause of academic science government and industry. and he freely admitted the determining influence here In everything that he undertook Steacie was the of the late Professor Maass. master-builder.Only the enduring was worthwhile Steacie received his Ph.D. in 1926 and remained and to endure the structure must have a solid founda- at McGill as Sterry Hunt Fellow until 1928. During tion and be built with quality imagination and care. this period his research involved mainly thermo- While his great abilities brought him eminence in dynamic studies including the determination of the everything he undertook he remained by preference solubilities and the rates of solution of hydrogen and the master-builder as fundamental research scientist. oxygen in silver. In the course of these latter studies * Delivered before the Society at King’s College London on October 10 1963. 73 methods were developed for making large single crystals of silver. Following his appointment as Lecturer in Chem- istry at McGill in 1928 Steacie began his first in- vestigation into chemical kinetics.The resulting paper entitled “The Kinetics of the Heterogeneous Thermal Decomposition of Methyl Formate” ap- peared in 1930 in the Proceedings of the Royal Society (London). It is interesting to note-and as well instructive of the state of that subject in 1930-that the words “free radical” do not appear in the publication. Pertinently one year earlier in 1929 Paneth and Hofeditz had reported the first detection of methyl radicals by the removal of metallic mirrors. Steacie was appointed Assistant Professor at McGill in 1930 and his main research efforts began to be centred around gas-phase oxidation reactions and the homogeneous and heterogeneous decom- positions of simple molecules.He became especially interested in the differences between the hetero- geneous and homogeneous modes of initiation of reaction. In the period 1930-1934 he published no less than thirty-five papers covering among other topics a wide range of kinetic studies. In 1932 he began a series of papers on the specific nature of energy exchange in unimolecular reactions taking the ethers as model systems. He studied the simul- taneous pyrolyses of dimethyl and diethyl ethers and his results at first indicated that their rates of decom- position were additive. Here it should be mentioned that the role of free radicals in these systems was not appreciated at the time. Further independent studies by Kassel and Steacie established that in these mixed systems there was a mutual activation of between 40 and 60%.Although Steacie had investigated several thermal decompositions in considerable detail in his earlier work it was in 1934 with a paper entitled “The Homogeneous Unimolecular Decomposition of Gaseous Methyl Nitrite” that he fist began to take serious cognizance of the role of free radicals in thermolytic processes. Here for the first time he noted Rice’s “Theory of Free Radicals” and sug- gested the first in a monumental series of reaction mechanisms involving free-radical species. This publication has real importance not only as a turning point in Steacie’s career but also to the then embryonic field of free-radical chemistry.The methyl nitrite reaction proved to be the first in a classic series of papers on the kinetics of decomposition of the aliphatic nitrites. In 1936 he published a general discussion of the relationship between chemical configuration and re- activity in terms of current theories of unimolecular reaction. Following his detailed examination of the nitrites Steacie noted that while the observed decline in rates with decreasing pressure in these systems was PROCEEDINGS accurately predictable by the Kassel theory no cor- responding explanation was furnished by the theory for the observed rate increase with molecular weight. Here it is illustrative of Steacie’s meticulous experi- mental technique to note that for the ethyl nitrite reaction he reported an activation energy of 37.7 kcal./mole and a frequency factor of 6.5 x 1013.In the most recently reported data on the same system the values are 37-5 kcal./mole and 6.1 x In 1934 and 1935 Steacie held an overseas fellow- ship from the Royal Society of Canada. In this period he worked in Bonhoeffer’s laboratory at Frankfurt and with Professor A. J. Allmand a King’s College. With K. H. Geib he published in 1935 a paper on exchange reactions involving atomic deuterium. And this work initiated a long series of studies of atomic reactions using the Wood-Bonhoeffer discharge system. By this time Steacie’s laboratory at McGill had become one of the major centres of kinetics research in the world. A very wide variety of gas-phase re- actions was under investigation in his laboratory and each system was examined with characteristic thoroughness and insight.For example the decom- position of diethyl ether was followed up to 260 atmospheres and data thereby became available on this important reaction over the pressure range 0.01 to 20,000 cm. of mercury. The results of this im- portant study provided strong support for a Rice- Herzfeld type of mechanism and therefore the reaction could no longer be regarded as a simple type of unimolecular process. In 1937 Steacie became Associate Professor of Chemistry at McGill. Academic life suited him well. He was a born leader with a boundless enthusiasm for his work and students flocked to his laboratory.Furthermore teaching came very naturally to him endowed as he was with a personality which unfail- ingly commanded respect a gift for exposition which few possess a brilliant analytical mind and a deep resonant voice which made listening to him a pleasure indeed. During this period Steacie published the results of a study of the pyrolysis of mixtures of dimethyl ether and perdeuteroacetone. The hydrogen product was found to consist exclusively of H and D, thereby precluding the suggestion made in earlier investiga- tions that formaldehyde the source of hydrogen decomposes by a chain mechanism since any hydrogen atoms in the system would have formed HD by abstractive attack on the heavy acetone. This deuterium-tracer study has broad significance since thereby a new technique was developed for deter- mining free-radical mechanisms in general.The method has found very wide applicability and forms the basis of a great many important mechanism studies which have been published since that time. MARCH1964 In 1938 Steacie published an extensive survey of the kinetics of the elementary reactions of simple hydrocarbons. This excellent review pointed out how rapidly this field of kinetics had developed since the participation of free radicals had begun to be appreciated. In his own laboratory he had initiated a new series of investigations of hydrocarbon systems. The simple alkanes were examined in detail with particular attention to the mechanism of nitric oxide inhibition of the chain processes in these reactions.In a paper on the n-butane reaction he made the important point that “The main defect of the NO- inhibition method is that the assumption that maximum inhibition corresponds to a complete sup- pression of all chains is arbitrary and makes cal- culated chain lengths of doubtful significance.” His own studies supported the idea that nitric oxide functioned only to reduce the mean chain length and not to eliminate chain reaction altogether. After considerable soul-searching Steacie ac-cepted in 1939 the Directorship of the Division of Chemistry at the National Research Laboratories in Ottawa. Few people realised at that time just how important this appointment would be to the future of science in Canada.For Steacie it was a radical change. By nature a gifted individualist with strong personal convictions and a deep dedication to his scientific work he flourished in an atmosphere of academic freedom. He had little sympathy for in- competence and little patience for bureaucracy. In his new position needless rules and pointless regula- tions irritated him. Nor did he take kindly to the endless committee meetings which ate away at his precious time for research. In his initial frustration he became penetratingly critical of government red- tape and the much-quoted author of some vitriolic remarks on that subject. However Steacie’s peculiar genius for mastering a situation soon came to his aid. Once he had examined the organisational structure in detail his quick mind soon saw ways whereby much of the dead growth could be cut out and that which could not be completely eradicated he learned to bypass with an adroitness which is the mark of the brilliant administrator.It rapidly became apparent to all those who dealt with him that this gifted scientist was also a man of formidable administrative abilities. Leadership radiated from him and he soon had the unswerving loyalty of all of the effective members of the Division of Chemistry. Several years before joining N.R.C. Steacie had become interested in photochemistry. What intrigued him was the concept of isolating individual free- radical processes and studying their kinetics by photochemical techniques. Indeed the real basis of his all-consuming interest in free-radical kinetics in general was the inviting possibility of singling out and measuring the kinetic characteristics of each rate element which in various complex combinations made up the overall rate processes in molecular de- compositions.His imagination was stimulated like those chemists who first conceived the elemental structure of matter by the idea of reducing kinetics to rate elements which could be separately charac- terised and thus their rate contribution to any actual kinetic process could be readily assessed. Photo- chemical scissions were highly specific and the result- ing free radicals could be generated in a cool sub- strate where they were usually thermally stable and therefore their structural pattern persisted in the ultimate reaction products a fact which facilitated enormously the identification and measurement of the rates of individual free-radical interactions.In his new laboratory at N.R.C. Steacie began to concentrate heavily on photosensitisation reactions initiated by the resonance states of mercury zinc and cadmium atoms. He quickly established in an important series of papers that the simple alkanes decompose by loss of a hydrogen atom to form the corresponding alkyl radicals. The products could be unequivocally explained in terms of disproportiona- tion and combination reactions of the alkyl radicals together with the abstractive attack of the primarily- formed hydrogen atoms on the substrate itself to form molecular hydrogen.Steacie’s studies especially in the field of mer~ury-6(~P,)-photosensitisation represent the major pioneering work in this im- portant region of free-radical kinetics. Practically all recent research in mercury photosensitisation can be directly linked to Steacie’s monumental contributions to this subject. Steacie was quick to realise that the study of reactions initiated by the electronic states of atoms could provide vital fundamental information on the nature of electronic energy-transfer processes a field which has recently achieved considerable promin- ence. Thus he was able to show that in hydrocarbon reactions initiated by triplet-excited cadmium atoms cadmium hydride is first formed in the primary step and this species he was able to detect by its resonance emission.In his studies of the exchange of energy between triplet-excited atoms and olefins he found that the olefin was thereby promoted to a higher energy level associated with the n-electron system. This energy-rich molecule could either be collisionally de-activated or decompose unimolecularly. The general pattern quickly became apparent from his detailed studies. If the olefin or diolefin was unsub- stituted the products of the unimolecular reaction were molecular hydrogen and an alkyne. Alkyl- substituted olefins and diolefins decayed from the excited state by loss of a hydrogen atom at the allylic position. These are the first important studies on reactions of the triplet states of molecules since it is now well established that the energy-rich olefin molecules first thoroughly studied by Steacie are actually triplet-excited species.Here again it can be said that it was Steacie’s work that provided the solid foundation and stimulated further research studies in what is now considered to be a major field of modern chemistry. Drawing on his considerable experience in the experimental techniques peculiar to the study of thermal decomposition reactions Steacie published with D. J. LeRoy in 1942 an important review article on “Experimental Methods for Determining the Activation Energies of Elementary Reactions.” This publication brought to a temporary halt his work on thermal systems and it was not until 1953 with the advent of considerably improved analytical techniques that he resumed his studies in this field.By 1944 Steacie’s reputation as an administrator was very well established and he was a natural choice for the position of Deputy Director under Sir John Cockroft of the joint British-Canadian Atomic Energy Project based in Montreal. It was of course a crash programme and Steacie found him- self managing a large group of highly-individualistic scientists who showed little aptitude or desire for the team effort required in such a wartime emergency. It was perhaps in this administratively nightmarish situation that Steacie’s genius for bringing out the best in people really came to the fore. The routine administrator surrounds himself with a cage of rules and regulations and the structure continues to grow until each individual in the organisation finds himself limited in his activities and constrained into routine effort.On the other hand Steacie subtly developed an administrative organisation so flexible and so unobtrusive that it only became apparent to the members of the group when they needed it to assist them in doing their best work. The only administra- tive regulations which interested Steacie were those that expedited the work and he therefore became known as the master under-administrator. AIl through the war years Steacie had kept his fundamental research laboratory in Ottawa in opera- tion and during this time he continued his studies in heavy-atom photosensitisation and on atomic reactions.In addition during that hectic period he had been working on the manuscript of the fiist edition of his now justly-renowned treatise on “Atomic and Free Radical Reactions.” The book appeared in 1946 and quickly established itself as the vademecum of the research kineticist. It was in the same year that he returned to the full-time directorship of the Chemistry Division at N.R.C. there turning his formidable energies toward the development of the Division into a first-rate scientific organisation. His own laboratory he quickly built up into one of the leading centres of research in chemical kinetics in the world. PROCEEDINGS It was also at this time that he conceived of the now-famous N.R.C.postdoctoral fellowship pro- gramme. It must be remembered that Steacie always remained the academic scientist in his basic attitudes. To him what made great universities great was the constant intellectual stimulation provided by the interaction between the staff and the ever-changing group of research students. He knew all too well that the fixed establishments characteristic of government laboratories often lead to channellised thinking and even stagnation. By his postdoctoral fellowship pro- gramme he was able to ensure a constant influx of young scientists who during their one- to two-year period as postdoctoral fellows would not only receive valuable training but in addition they would furnish the vital component necessary for generating that atmosphere of intellectual inter-action in which real scientific creativity flourishes.In the post-war years under Steacie‘s brilliant but unobtrusive guidance the Chemistry Division of the National Research Laboratories in Ottawa became a mecca for research scientists. In his efforts Steacie was extremely fortunate in having as President of N.R.C. the distinguished scientist Dr. C. J. Mackenzie. Obviously in the short span of this lecture justice cannot be done to the enormous con- tributions of Dr. Mackenzie to the development of the Council. The distinguished subject of this lecture would have been the first to give the major credit for any administrative accomplishment attributed to him to Dr. Mackenzie to Dr. Leo Marion to Dr.B. G. Ballard and to the many other excellent scientists and administrators who worked with Steacie in close co operation toward the achievement of mutually-agreed objectives. Ned Steacie the man would then have taken those of his accomplishments which even modesty could not transfer to his col- leagues and attribute them to the real inspiration of his life-his beloved and devoted wife. As a result of his considerable contribution to the war effort Steacie was awarded the O.B.E. in 1946 and in that same year he received the first of the no less than eighteen honorary degrees later bestowed upon him in the remaining sixteen years of his life. By 1946 Steacie had published 125 papers. His own reputation attracted gifted young postdoctorals to his laboratory and in the ensuing decade he pub- lished some of the most brilliant work of his career.Recognition of his accomplishments came quickly. He was elected Fellow of the Royal Society in 1948 and in 1949 he became President of the Chemical Institute of Canada. In 1950 a major turning point came in his career with his appointment as Vice- President (Scientific) of N.R.C. As Vice-President Steacie assumed wide responsi- bilities for the overall direction of the National MARCH1964 Research Laboratories and at the same time he formally became a member of the Honorary Ad- visory Council the Research Council proper-a nationally-representative body of academic and in- dustrial scientists. All matters over which N.R.C.has jurisdiction are referred to this Honorary Advisory Council. In 1946 he became interested in studying the rates with which methyl radicals abstract hydrogen atoms from various hydrogen-containing compounds. Methyl radicals play a vital role in the free-radical reactions of many organic compounds and little information was available at that time on the activa- tion energies and frequency factors for this important class of free radical process. To generate the methyl radicals in situ he first examined the photolysis of dimethylmercury and some preliminary data were obtained with butadiene and isoprene as the hydro- gen donors. However his major work on methyl- radical reactions was initiated in 1951 with the publication of a detailed study of the photolysis of acetone at higher temperatures.This system proved to be a highly-reproducible source of methyl radicals suitable for quantitative work on abstrac- tion reactions. Before this reaction can be used how- ever as an in situ source of methyl radicals in the presence of an added hydrogen donor RH it is necessary to determine the activation energy and frequency factor for the removal by methyl radicals of a hydrogen from acetone itself. This basic reference rate was determined with great care and shortly thereafter Steacie began to publish a long series of important papers on the CH f RH re- action. Two major methods were developed the first involved the photolysis of “light” acetone in the presence of the RH substrate and in the second perdeuteroacetone was photolysed to form CD radicals and these attacked the heavy acetone to yield CD, while their reaction with the added RH compound resulted in a CD,H product.This elegant method yielded the relative rate of removal of hydro- gen atoms from the RH substrate compared to the corresponding reaction with the heavy acetone. The relative rate could be determined by simply measur- ing the CD,H:CD ratio in the methane product with a mass spectrometer. Steacie’s important work on methyl-radical abstraction reactions provided much-needed activa- tion energy data for elementary processes occurring in a wide variety of systems. In addition these search- ing studies firmly established two methods for deter- mining accurate data on rates of abstraction by methyl radicals from hydrogen-containing substrates.In April 1952 upon the retirement of Dr. C. J. Mackenzie Steacie became President of the National Research Council. There are few men indeed who could have been more ideally suited for this vital position in Canadian Science. Universally respected as one of the great scientists of his time and at the same time regarded by the government and by the people as Science’s most eloquent and most com- prehensible spokesman he was in an ideal position to influence the course of scientific development in Canada. Characteristically he moved ahead with amazing rapidity on all fronts. Within the Council he strengthened its scientific position by the appoint- ment of a number of distinguished scientists to the staff.Now very much the master diplomat he estab- lished strong ties of mutual respect with key govern- ment officials thereby very much facilitating his negotiations with the government. As President he also became Chairman of the Honorary Advisory Council. Under Steacie’s guid- ance this Council became a highly-unified body working concertedly for increased support of scientific research in Canada. Each year major in- creases were obtained in the funds available for operating and equipment grants to the universities. In addition Steacie managed to obtain special allo-cations for the financing of major scientific instalia- tions at the universities such as accelerators van de Graaf generators and other costly high-energy equipment for nuclear research.What is more through his efforts the postdoctoral fellowship pro- gramme was extended to the universities and to other government departments thereby increasing the research opportunities for young scientists in Canada. In 1953 Steacie was Baker Visiting Lecturer at Cornell University. During this period he was able to complete the second edition of his monumental work on “Atomic and Free Radical Reactions.” For this second edition which was published only eight years after the first it was necessary that the work be completely re-written and expanded to almost double its former size in order to include even brief mention of the enormous number of research papers published in free-radical kinetics during the inter- vening period.Of this body of new research work a very significant fraction had come from Steacie’s own laboratory. As President of N.R.C. Steacie became in- creasingly interested in the interactions between science and government. Here true understanding is difficult. While it is a simple matter for governments to comprehend the wisdom of investing large sums of money in end-use research the economic advan- tage of similar expenditures for long-range basic research are not so apparent. There is therefore a tendency for governments to support only work which is of immediate functional interest to them. In modern science this is a serious problem since funda- mental research is now a very expensive undertaking which cannot be adequately financed except on a national basis.Hence there is a very real danger of governments through their control of the purse- strings adversely influencing the normal course of development of science. Under such conditions as every scientist knows the spring of new ideas dries up and all meaningful research ultimately grinds to a halt. Steacie’s signal success in putting the abstract concept of fundamental research across to a lay government was probably attributable to a com- bination of many unique qualities that he possessed. In the first place he was a man who carried great conviction with everything he said. Furthermore before making his case he always carefully examined the points of view of those whose support he sought.Never was he guilty of underestimating his adversary. This is a lesson which could be learned with profit by many administrators. Continuing success is never accidental. Even during his extremely bix$y years as President of N.R.C. Steacie continu28Xs free-radical studies. Indeed in the last decade of his life he published no less than 74 papers which brought his total publica- tions to 235 which would constitute an enormous productivity even for a very active scientist who devoted himself exclusively to research. In his research studies he showed a continuing willingness to re-examine various systems applying the most advanced techniques available under the optimum experimental conditions.With a youthful enthusiasm tempered only by objectivity he would refine and even radically re-interpret his own previous work in the light of new data. He advocated the immediate dissemination of new findings as opposed to publication only after an exhaustive investigation on the basis that all investigators should be apprised as quickly as possible of the most recent develop- ments in a field. As President of N.R.C. he became increasingly involved in international scientific activities. He was by accomplishment and by innate ability the finest representative of Canadian Science. In 1957 he was made Honorary Fellow of this Society and at the same time he was elected Vice-president of the Faraday Society becoming its President in 1959.From 1958 to 1961 he served as a Member of the International Advisory Committee on Research in the Natural Sciences of U.N.E.S.C.O. and at the same time he was Canadian Representative on the Science Committee of N.A.T.O. In 1958 he also became associated with the International Council of Scientific Unions the main non-government organi- sat ion for co-ordinating international activity in science. He was elected President of I.C.S.U.in 1961. In order meaningfully to assess Steacie’s contribu- tions to the field of chemical kinetics it is extremely important to take into account the nature of the PROCEEDINGS subject itself. It is not a field in which one or two brilliant flashes of creative insight could suddenly transform chaos into order.And this was most certainly true at the time when Steacie first began his investigations. What must be borne in mind is that Steacie was one of the first kineticists to realise that to elucidate the mechanisms of overall kinetic pro- cesses the elementary reactions of the free-radical intermediates themselves must be separately studied in detail. He remained throughout the thirty-five years of his research career a strong proponent of this approach. And while he made extensive studies of thermal decompositions photolyses photosensi- tisations and other methods of generating atoms and free radicals these techniques he regarded as primarily important not in themselves but as methods whereby the radical species could be separately produced and kinetically studied.The field of free-radical kinetics in its early years was fraught with formidable experimental difficulties which today have at least partially been overcome. The lack of a comprehensive theory inadequacy of analytical techniques the dearth of high-purity substrates and the limitations imposed by the general level of technical development all combined to frustrate efforts to uncover the vital dynamics of reaction systems. Steacie dedicated his research career to obtaining meaningful kinetic data on the rates of elementary processes. The magnitude of his contribution can only be properly appreciated when it is viewed as a whole. It is then that one realises that this highly-creative scientist was a major architect of the modern structure of free-radical chemistry.It is not however by his research publications alone that Steacie contributed to the continuing development of his field. Under his stimulating in- fluence his laboratory in Ottawa became the major centre for fundamental research in atomic and free- radical reactions. Many brilliant young scientists associated themselves with his research group and in turn left to develop at various institutions through- out the world their own laboratories for the training of photochemists and free-radical kineticists. Steacie’s reputation as a scientist however goes far beyond the confines of free-radical chemistry. He is held in very high esteem by many scientists and even more distinguished laymen who know essentially nothing about his monumental work in his field of research interest.Here we see Steacie in the broader context of science and society. His was an unselfish devotion to the advancement of science in every sense of the word. It is rare indeed that in one man there are combined the penetrating intelligence and the creative insight of the great research scientist the organisational genius of the master administrator and the broad vision and arresting personal mag- MARCH1964 netism of the statesman. And to these great gifts all those who had been privileged to know him would quickly add those rare indefinable qualities which mark the warm human being and the loyal friend. This was Steacie. There are few scientists who have given so much of themselves for the development of their country.Steacie knew that the growth of Canada as an independent nation would depend in large measure upon the contributions of its scientists. He knew as only a distinguished scientist could know what was particularly necessary in order to provide that en- vironment in which science and scientists flourish. This is an especially serious problem in Canada where for many years there has been a crippling loss of its promising young scientists to the United States. Steacie always at heart the academic scientist realised fully that healthy scientific growth starts in the universities. He chose however first to con- centrate his energies on the National Research Laboratories.This was typical of his political acumen. He knew that it would be a simpler matter to convince the Federal government to develop its own national laboratories than it would be to persuade it to enter the politically-contentious region where Federal and Provincial jurisdictions overlap. He was equally certain that any pattern of growth established in the national laboratory could then readily be transferred to the universities. He saw also another advantage in proceeding in this fashion. Canadian universities had long been hampered in their growth by their inability to attract and retain a significant number of really able men in the sciences. Steacie’s plan was to build up the national laboratories to a high scientific level.He hoped thereby to provide a pool of first-rate scientists for the universities. Under his guidance the National Laboratory rapidly grew into an organisation in which even the best scientists found it a privilege to work. The post- doctoral fellowship programme provided profes- sional research groups for the N.R.C. staff and this was an important asset in attracting good scientists to the Council. In turn many of the N.R.C. fellows took staff positions in Canadian universities and others returned to their native country carrying with them the good name of the N.R.C. Laboratories and helping to establish Canada as a respected member of the international scientific community. Steacie’s beneficial influence reached into every region of scientific activity in Canada.He believed in individuals not organisations. He spent a great deal of his time in assisting universities in obtaining the best scientists for their staffs. The provincial research councils benefited greatly not only by his advice in staff recruitment but also by his efforts in obtaining increased federal support for their long- range research rogrammes. In the latter years of his life he began to con- centrate heavily on the upgrading of scientific research in indu try. He Norked closely with in- dustrial leaders in Canada toward the strengthening of industrial research hboratorjes and toward the more effective utilisation of scientists by Canadian industry. He was instrumental in obtaining special tax concessions to assist industry in financing re- search and in addition he pioneered a new pro- gramme of federal research grants for the support of industrial research projects-a revolutionary con- cept which will be of enormous benefit to Canadian industry and will serve as an example to ot,her countries of what must be done to provide a con- tinued industrial development in the future.Members of the Chemical Society your lecturer has attempted albeit inadequately but most sincere- ly to pay a fitting tribute to the memory of a truly great modern scientist one who has made each of us proud to be able to say we are a member of the same profession. In closing may your lecturer be permitted to record the tragic and untimely loss of a very warm and valued friend.COlClMUNICATIONS The Nitration of Octaethylporphyrin By R. BONNETT and G. F. STEPHENSON* INTERESTin the reactivity of the meso-position of porphyrins and related compounds especially in relation to the biological degradation of the natural pigments led us to examine the nitration of 1,2,3,4,5,6,7,8-0ctaethylporphyrin(Fischer nun1 ber- ing). Earlier nitration studies1 on less symmetrically substituted porphyrins had given complex results but in certain cases mononitro-compounds were iso- lated. The structures of these have remained obscure certain chemical evidence was considered’ to indicate meso-substitution while side-chain substitution was suggested2 on the basis of apparent regularities in the visible spectra of porphyrins.The nitramine structure is a third reasonable possibility. * Chemistry Department Queen Mary College London E. 1. Fischer and Klendauer Annalen 1941 547 123 and references therein. Stem and Molvig 2.phys. Chern.(Leipzig) 1936 A 177 365. 80 Nitration of octaethylporphyrin followed by chromatography gave red-brown rhomboids demon- strably free from starting material (thin-layer chromatography). Total analysis was consistent with the mononitro-formulation and the infrared spec- trum confirmed the presence of the nitro-group [1532 cm.-l (in CH2C1,) and 1378 cm.-l (in CCl,)] while arguing against the nitramine structure. The nuclear magnetic resonance spectrum3p4 of octa-ethylporphyrin in deuterotrifluoroacetic acid had a singlet at -0.98 r corresponding to four protons while the mononitro-compound had two signals in this regian one at -0.85 r (2 protons) and one at -0.76 r (1 proton).The most likely interpretation is that nitration has occurred at a meso-position and that the signals represent the (#3 3-6)-and 7-protons respectively. A similar situation is observed in meso-methyleti~porphyrin~ but not in N-methyl- etiop~rphyrin;~ Associated wich the alkyl groups PROCEEDINGS there are no deshielded protons and hence a side-chain nitro-group is unlikely. The spectrum of the nitro-derivative shows a general shift to high field presumably due to a reduced ring current but certain of the alkyl protons show a considerable shift. This is considered to arise from a combination of effects operating in the region of the meso-substituent [(i) displacement of alkyl groups from the plane caused by overcrowding and (ii) the long-range shielding of certain alkyl groups by the non-coplanar nitro-function1.Octamethylporphyrin and mesoporphyrin undergo a similar reaction although from the latter a mixture of mononitro-compounds appears to be formed. The apparent reactivity of the methine bridge of a por- phyrin presents a mechanistic problem which is being further investigated. (Received December 17th 1963.) a Abraham Jackson Kenner and Warburton J. 1963 853 and references therein. Woodward and Skaric J.Amer. Chem. SOC.,1961 83 4676. Caughey and Iber J. Org. Chem. 1963,28 269. A Novel Synthesis of Tetra-alkyl Hypophosphates By J.MICHAL~KI and A. ZWIERZAK* ORGANOPHOSPHORUS compounds containing the direct P-P bond are relatively unknown. The study of tetra-alkyl hypophosphates (I) has been hampered by lack of a convenient method of preparation. Esterification of anhydrous hypophosphoric acid by diazoalkanes1s2 is unsuitable because of poor accessi- bility of anhydrous hypophosphoric acid. The action of methyl iodide on silver hypophosphate leads to a mixture of hypophosphate and pyr~phosphate.~ Attempts to build the hypophosphate molecule from two monophosphorus fragments have so far been only partly succe~sfu1.~~~ (RO),P.ONa + Cl.P( :O)(OR) 3 (RO),P( :O)-P( :O)(OR)2 (I) + NaCl The condensation of sodium dialkyl phosphites with dialkyl phosphorochloridates has therefore been studied a similar reaction having led success- fully to tetra-alkyl dithiohypophosphates.6 Pure tetraethyl hypophosphate was obtained in 53 % yield when diethyl phosphorochloridate was added at 0-5”’ to a 50% excess of a benzene solution of sodium diethyl phosphite.Sodium chloride was pre- cipitated by the addition of petroleum and the hypophosphate was distilled in vacuo. Its physical constants are in good agreement with those given by Baudler,2 and the characteristic frequency2 of the P-P bond (at 257 cm.-l) was observed in the Raman spectrum. Hydrolysis of the ester (I; R = Et) gave diethyl phosphite and diethyl hydrogen phosphate in almost quantitative yield and chlorination by sulphuryl chloride afforded diethyl phosphoro-chloridate in 55 % yield.(Eto)2P(:0)-0-P( :0)(OEt)Et (11) (EtO),P( :O)-O-P(OEt) (111) We have also found that the product of thermal condensation of diethyl phosphorochloridate with triethyl phosphite described6 contains only minute amounts of the tetraethyl hypophospate (I) being mainly a mixture of the anhydride and the phosphorous phosphoric anhydride (111). (Received December 30th 1963.) * Department of Organic Chemistry Technical University of Lodz Politechnika Poland. Baudler 2. Nuturforsch. 1953 8b 326. Baudler 2. anorg. Chenz. 1956 288 171. * Remy and Falius 2. anorg. Chem. 1955 282 217. * Unpublished results from this Laboratory; Michalski and Modro Chem.and Ind. 1960 1570. Almasi and Paskucz Chem. Ber. 1963,96,2024. Petrov Blimyuk and Burygin J. Gen. Chem. (U.S.S.R.) 1959 29 1486. Baudler and Giese 2.anorg. Chem. 1957 290 258. MARCH1964 Pyrolysis of Sulphoxides; A Steric Effect By D. NEVILLE JONES and M. A. SAEED* THE pyrolytic elimination of esters xanthates? amine oxides and sulphoxides4 to give olefins have been shown to proceed predominantly in a cis-manner by an intramolecular mechanism. Steric interactions in the cyclic transition state can affect both the direction of eliminati~n~~,~ and the ratio of cis-olefin to trans-olefin formed.3a Rationalisations of product ratios on steric grounds have been confined to a consideration of the non-bonded repulsions between substituents on the a and 18 carbon atoms,3s5 and have neglected any steric effects due to the leaving group.With esters and xanthates the leaving g8oup is planar and these effects are not important but with amine oxides and sulphoxides steric repul- sions due to the alkyl substituents on nitrogen and sulphur could exert a significant effect upon the direction of elimination. We have found that intramolecular steric inter- actions involving the leaving group can determine the direction of pyrolytic elimination in certain sul- phoxides. In refluxing benzene solution 3p-acetoxy- (R)-5a-methylsulphinylcholestane (I ; R = Ac) decomposed (after 3 hr.) to give only 3p-acetoxy- cholest-4-ene (86%) whilst 3p-acetoxy-(S)-5a-methylsulphinylcholestane(I1; R’ = Ac) under the same conditions gave mostly 3~-acetoxycholest-5-ene (65 %) and some 3p-acetoxycholest-4-ene (20%).Models show that in their most stable conformation the sulphoxide oxygen in the acetoxy-sulphoxide (I; R = Ac) lies in a position favourable for intramole- cular cis-extraction of the 4 a-hydrogen atom (see 111) and the sulphoxide oxygen in the isomeric sulphoxide (11; R = Ac) is favourably placed for abstraction of the 6a-hydrogen atom (see IV). The conformations of (I; R’ = Ac) and (11; R’ = Ac) which would lead to abstraction of the 6a-and 4a-hydrogens respectively are destabilised by strong non-bonded interactions between the S-methyl group and the la-and 9a-hydrogen atoms. The configuration of the acetoxy-sulphoxides (I; R’ = Ac) and (11; R’ = Ac) was confirmed as follows.Mild hydrolysis gave the corresponding hydroxy-sulphoxides,(I; R’ = H) and (11; R’ = H) which were severally treated with methanesulphonyl chloride in pyridine at 0”.The hydroxy-sulphoxide (11; R’ = H) gave the corresponding methane- * Chemistry Department Sheffield University. Barton J. 1949 2174. Hiickel. Tame. and Lemtke. Annalen. 1940. 543.191. sulphonate (11; R’ = Me-SO,) whereas the hydroxy- sulphoxide (I; R’ = H) gave the alkoxy-sulphonium chloride salt (V). The most stable conformation of the methanesulphonyloxy-sulphoxide (I ; R’ = MeSO,) is such that intramolecular nucleophilic dis- placement of the 3~-methanesulphonyloxy-group by sulphoxide oxygen can occur.Such internal salt formation is difficult for (11; R = MeSO,) because the transition state would be severely destabilised by steric repulsion between the S-methyl group and the 9 a-hydrogen atom. The acetoxy-sulphoxides (I; R’ = Ac) and (11; R’ = Ac) were prepared from 318-acetoxy-5 a-mercapto- cholestane6 by S-methylation with diazomethane followed by oxidation to the isomeric sulphoxides (separated by thin-layer chromatography) with hydrogen peroxide in acetic acid. Oxidation of the acetoxy-sulphoxides (I; R’ = Ac) and (11; R’ = Ac) to the same 3~-acetoxy-5a-methylsulphonylchole-stane showed that they differed only in the con- figuration about the sulphur atom. The difference in steric requirements between a planar and non-planar leaving group may also be a contributing factor in the marked difference between the ratio of menth-3-ene to menth-2-ene obtained by pyrolysis of the methyl xanthate of menthol2 (70 30) and NN-dimethylmenthylamine N-oxidesa (35 :65).(Received February 5th 1964.) (a) Code GBd Lee a6d Moore J. Amer. Chem SOC.,1957,79,4720; (b)Sahyan and Cram ibid. 1963,85 1263. Kingsbury and Cram J. Amer. Chem. SOC.,1960,82 1810. (a) Copeand Acton J. Amer. Chem. Soc. 1958,80,355; (b)Cope Ciganek and Lazar ibid. 1962 84 2591 Komeno Chem. Pharm. Bull. (Tokyo) 1960,8,672. PROCEEDINGS The Synthesis of [18]Annulene Trisulphide By G. M. BADGER, J. A; ELM,and G. E. LEWIS* THE molecular orbital theory of unsaturated and aromatic compounds developed by Huckel pre- dicted that cyclo-octadecanonaenel ([18lannulene; I) would be aromatic and the observed properties2s3 support this view.It seemed of interest to prepare heterocyclic analogues having additional possibilities of conjugation via hetero-atoms and we now report a synthesis of [18]annulene 1,4-7,10-13,16-trisu1- phide (11). In this compound three heterocyclic rings are linked by three vinyl groups; in porphyrins four heterocyclicrings are linked by four methine groups. The two key intermediates thiophen-2,s-diacetic acid m.p. 189-190’ and methyl cis-a/I-di-(2- formyl-5-thienyl)acrylate,m.p. 120-1 22’ were con- densed in acetic anhydride and triethylamine to give a product which was esterified to give methyl 1,4-7,€6-13,16- triepithio [18]annulene -5,11,18-tri -carboxylate m.p.257-259”. Xvdrolysis of the ester gave the tricarboxylic acid m.p. > 360’ which was decarboxylated by treat- ment with copper chromite in quinoline at 210-220”. The required trisulphide (11) formed yellow plates m.p. 74.5-75.5’ (from aqueous ethanol) v (in CHCl,) 1600 cm.-l Amax. 204 (E 18,OOO) 224 (E (1) 16,800) and 288 mp (E 17,300) with tailing into the visible region. The n.m.r. spectrum (in CCl,) showed two peaks of equal area (7 3.32 and 3.27) in agree- ment with a structure having equal numbers of two types of Proton. (Received December 23rd 1963.) * Organic Chemistry Department University of Adelaide Australia. Sondheimer atld Wolovsky J. Amer. Chem. SOC.,1962,84,260.Jackman Sondheimer Amiel Ben-Efraim Gaoni Wolovsky and Bother-By J. Amer. Chem. Soc. 1962,84,4307 a Sondheimer and Gaoni J. Amer. Chem. SOC.,1960,82,5765; Bregman and Rabinovich Acta Cryst. 1960,13,1047. The Structure and Synthesis of Cannabigerol a New Hashish Constituent By Y.GAONI and R. MECHOULAM* CHROMATOGRAPHY of a hexane extract of hashish on “Florisil” afforded a hitherto unknown component C21H,,(OH), m.p. 51-53’ for which we suggest the name cannabigerol and assign structure (I). The ultraviolet spectrum of cannabigerol is identical with that of cannabidiol (II).ls3 The absence of optical rotation suggested that the two asymmetric centres present in (11) are absent in cannabigerol. As the latter has two hydrogen atoms more than cannabi- diol but the same number of double bonds it seemed plausible that the carbon-carbon bond be- tween the two asymmetric centres in (11) does not exist in (I).The n.m.r. spectrum indicates that (a)the two aromatic hydrogen atoms are magnetically equi- valent which is compatible with the usual olivetol moiety present in Cannabisconstituents (b)the pro- tons of the methylene group at C-8 are strongly de- shielded and split by a single adjacent proton which is presumably due to a ds-double bond and (c) a d2-double bond is present. These findings are com- patible only with structure (I). (a geraniol(II1) with olivetol (IV) in decalin for 36 hr. The natural and synthetic samples were identical (spectra chromatography ,m.p.). In Nature cannabigerol is probably formed by condensation of geranyl pyrophosphate with olivetol.Thus from a biogenetic point of view cannabigerol represents the primary product and a missing link in the formation of Cannabis constituents. Conversion into cannabidiol (11) tetrahydrocannabinol and cannabinol is biogenetically plau~ible.~ Cannabigerol has been synthesised by boiling (Received January 7th 1964.) * The Daniel Sieff Research Institute Weizmann Institute of Science Rehovoth Israel. Mechoulam and Shvo Tetrahedron 1963,19 2073. Mechoulam,J. Org. Chem. (submitted for publication). a Adams Chin McPhee and Wearn J. Amer. Chem. SOC.,1941 63 2209; Korte and Sieper Annalen 1960,630 71. Prepared by a modification of the method of Suter and Weston J.Amer. Chem. Soc. 1939 61 232. Whaley in “Chemistry of Natural Phenolic Compounds,” ed. by Ollis Pergamon Press London 1961 p. 20. MARCH1964 Synthesis of Mycinose By J. S. BRIMACOMBE and L. C. N. TUCKER* M. STACEY MYCINOSE,a sugar component of the antibiotic chalcomycin,' has been identified2 as 6-deoxy-2,3-di- 0-methyl-D-allose (I). We now report a synthesis of mycinose which confirms this structural assignment. Reaction of 2,3-O-isopropylidene-5-O-tosyl-~-rhamnof~ranose~ (11) with sodium methoxide at methyl+-allose (I) m.p. 100-102" [cc]E -41" (3 min.) + -29" (final) (c 1.5 in H20) (lit.2 m.p. Ho TsO Me \ P o\,o /c\ C Me Me deb (n) (~);R=H (IV) ;R=PhCH room temperature takes pla~e~9~ with inversion of configuration at C-4 and C-5 to yield methyl 6- deoxy-2,3-O-isopropylidene-/3-~-allofuranoside (111; R = H).The derived benzyl ether (IV; R =PhCHp) was deisopropylidenated in boiling 1 % methanolic hydrogen chloride; the product on methylation afforded methyl 5-O-benzyl-6-deoxy-2,3-di-O-methyl- a/3-~-a]lofuranoside. Removal of the bemy1 group with hydrogen over palladium+-harcoal,5 followed by acidic hydrolysis gave 6-deoxy-2,3-di-O- MeO (1) 102-106" [cc]~-46" -f -42" (2 min.) -+ -29" (c *56in H2°)) ;i*r* (*r) indis-tinguishable from that Of (Received February 7th 1964.) * The Chemistry Department The University Birmingham 15. Parke Davis and Co. Belg. P. 587,213/1960. Dion Woo and Bartz J. Amer. Chem. SOC.,1962 84 880. Reist Goodman Spencer and Baker J.Amer. Chem. SOC.,1958 80 3962. Levene and Compton J. Biol. Chem. 1936 116 169. Mozingo Org. Synth. 1946 26 77. Pentafluoro- and Chlorofluoro-Pyridines By R. D. CHAMBERS and W. K. R. MUSGRAVE" J. HUTCHINSON THEonly routes so far described to pentafluoro- pyridine have involved the preparation of undeca- fluoropiperidine and its defluorination in such low overall yields as to preclude the use of the process as a useful preparative method.112 Chlorofluoro-pyridines containing hydrogen and with small numbers of fluorine atoms have been made by heat- ing the corresponding chloropyridines with potas- sium fluoride in a ~olvent.~ We now report the Preparation of pentafluoropyridine (b.p. 84" Amax. 2568 8 in cyclohexane) 3-chlorotetrafluoropyridine (b.p.119" Amax. 2617 L$ in cyclohexane) and 3,5- dichlorotrifluoropyridine (b.p. 159-160" Amax. 2662 8 in cyclohexane) by heating pentachloro- pyridine with potassium fluoride. When a solvent (sulpholane) was used the main product was 3,5-dichlorotrifluoropyridine together with a small amount of 3-chlorotetrafluoropyridine. In an auto- clave at 400-500" and in the absence of a solvent the total yield of halogenated product was about SO% and its composition could be varied from C,C12F3N (100%) to C,F5N (90%) by altering the temperature and time for the reaction. Since penta- and tetra-chloropyridines are obtain- able in 30-35% total yield from pyridine? this method forms a convenient route to the important intermediates mentioned above.Of the three possible isomers of tetrachloro-pyridine only those with hydrogen atoms in the 3- and the 4-position were obtained. The conditions under which pentafluoropyridine is produced from pentachloropyridine caused complete decomposition of the tetrachloropyridines ; this instability must be due to the presence of hydrogen in the molecule. So far we have been unable to replace by fluorine the chlorine atoms in the 3- and the 5-position of the tetrachloropyridines and even those in the 2- 4- and 6-positions are less easily replaceable than those in pentachloropyridine. As would be expected pentafluoropyridine will react with nucleophiles the fluorine atom in position 4 being most easily replaced. We have prepared 4-amino- and 4-hydrazino-tetrafluoropyridines, and the latter has been converted into the former by reduction with hydrogen iodide.Preliminary reac- tions show that the chlorine atoms in chlorofluoro- pyridines have useful functional properties e.g. Grignard reagents can be prepared and catalytic reduction affords the corresponding hydro-com- pounds. (Received February 5th 1964.) * The University of Durham. Burdon Gilman Patrick Stacey and Tatlow Nature 1960 186 231. Banks Ginsberg and Haszeldine Proc. Chem. Soc. 1960 211. Finger Laurence Starr Dickerson Gutowsky and Hamer J. Org. Chem. 1963 28 1666. Forthcoming publication. PROCEEDINGS The Photo-dimerisation of 2,4-Dimethylcoumalin:The Synthesis of 1,3,5,7-Tetramethylcyclo-octatetraene By P.DE MAYOand R. W. Yrp* THE photo-dimerisation of 2-pyridones leads to the formation of 1,4-dimersfs2 and not to 1,2- or 1,2- 1,4-dimem3 Similar observations were made with 2-aminopyridine~.~.~ If a similar dimerisation of a 2-pyrone could be induced a route to cyclo-octa- tetraene derivatives might be available by taking advantage of the ready decarboxylation of endo-cyclic flyunsaturated lactones. Irradiation (Pyrex filter) of 4,6-dimethyl~oumalin~ in a saturated benzene solution5 gave rise to a number of dimers separable by chromatography.6 Of these dimer A [m.p. 245" (sublimes)] and dimer B [m.p. 182-184"] on brief heating above the melting point gave 1,3,5,7-tetramethylcyclo-octatetraene (111) (m.p.69-70") (spectra and analysis) together with a small amount of coumalin. The n.m.r. spectra showed two peaks only (ratio 1:3) at r 4.65 and 8-32.' Dimers A and B are thus synlanti-stereo- isomers of structure (I). Dimer C [m.p. 152-154'1 on spectral evidence was assigned the structure of one of the synlanti-cisltrans-isomersof (11) that is a 1,2-dimer. At 160" this isomer was rapidly con- verted into dimer B. This conversion at low temperature is indicative of a Cope rearrangement already well-known in the cis-divinylcyclobutane system and requires there- fore the stereochemistry indicated in (IV) for dimer C. Dimer B must accordingly be assigned stereo- structure (V),leaving dimer A as (VI). The present results provide a serviceable route to the hydrocarbon.Thus coumalin (17 g.) gave (allow- ing for 4.4 g. of recovered material) a 26% yield of the cyclo-octatetraene. OWo A -(W (Received February 3rd 1964.) * Department of Chemistry University of Western Ontario London Canada. Ayer Hayatsu Mayo Reid and Stothers Tetrahedron Letters 1961 No. 18 648 ;Paquette and Slomp J. Amer. Chem. SOC.,1963,85 765. Taylor and Kan J. Amer. Chem. SOC.,1963 85 776. Taylor Kan and Paudler J. Amer. Chem. SOC.,1961 83 4484. Wiley Org. Synth.. 1952 32 57 76. Irradiation of a suspension of the coumalin in the saturated solution gave similar results. Adequate analyses have been obtained for all new compounds. Spectral data are in agreement with assigned structures. The temperature dependence of these peaks (Anet J.Amer. Chem. SOC.,1962 84 671) (very closely spaced multi- plets) will be reported later in collaboration with Dr. J. B. Stothers. Vogel Annalen 1958 615 1. A Novel Rearrangement in the Catechin Series By C. A. ANIRUDHAN and W. B. WHALLEY* D. W. MATHIESON INaddition to the epimeric 2-acetates (1) obtainedf by acetolysis of tetra-0-methyl-( +)-catechin toluene- p-sulphonate we have isolated in moderate yield a third product C,,H,O(OMe),(OAc) m.p. 82" [aID+ 29.7" the constitution of which has been established as (11; R = OAc). * The School of Pharmacy University of London. Mehta and Whalley J. 1963 5327. Bokhari and Whalley J. 1963 5322. Thus hydrolysis of (11; R = OAc) yields (11; R = OH) which is oxidised by manganese dioxide to a mixture of 2-(3,4-dimethoxyphenyl)-4,6-dimethoxy-coumarone (111; R = H)2 and the corresponding 3-formyl derivative (111; R = CH0).2 Reduction of the mesylate (11; R = 0.S02Me) with lithium MARCH1964 aluminium hydride furnishes 2-(3,4-dimethoxy-phenyl)-4,6-dimethoxy-3-methylcoumaranone (I1;R = H) [a] + 14.9” the n.m.r.spectrum (in CDCI,) of which includes a doublet at r 8-57 (J 6 c./sec.) (> CHMe 3 protons). Dehydrogenation of (11; R = H) affords 2-(3,4-dimethoxyphenyl)-4,6-dimeth-oxy-3-methylcoumarone (111; R = Me). This was synthesised by the Wolff-Kishner reduction of (111; R = CHO).2 The formation of (11; R = OAc) most probably proceeds by the migration of the phenyl ring A of the catechin system from C-4 to C-3 as in (IV).The absolute configuration of (11; R = OAc) and its derivatives may provisionally be defined as in (11). N.m.r. data do not unequivocally define the relative stereochemistry of the protons at C-2 and C-3 in (11; R = OAc) and its derivatives. The production of (11; R = OAc) is apparently the first example of the conversion of a chroman derivative into a coumaranone under mild solvolytic conditions although the formation of 2-aryl-Jurd Chem. and Ind. 1963 1165. coumarones from flavylium salts by the action of hydrogen peroxide3 is superficially analogous. H OMe OMe OMe (1) MeO~o&~tvle OMe cm) MeOaok-@le OMe HCHP (a> Wai6:Me me 4 4OT5 (1 v) [aID’sare in chloroform. All compounds had the requisite spectral and analytical properties.(Received February Sth 1964.) Synthesis of (f)-Isothebaine By A. R. BATTERSBY and T. H. BROWN* THE aporphine alkaloids isothebaine (IV) and stephanine (V) have unusual oxygenation patterns.l It was suggested2 that bases of this type are bio- synthesised from the l-benzylisoquinoline (I) by phenol-oxidation3 to give the dienone (11) followed by reduction to the dienol (111). Dienol-benzene re- arrangement* may then occur and four ways are theoretically open leading to variously substituted aporphines. That illustrated generates isothebaine (IV) the major alkaloid of Papaver ~rientale.~ This reaction sequence has now allowed the first synthesis of (f)-isothebaine to be achieved.The phenol (I) prepared by standard methods,6 was oxidised by alkaline ferricyanide to give a mix- ture of dienones (4%) from which two were isolated crystalline. One (vmax. 1665 1630 1605 cm.-l in CHCl,) showed the expected methyl resonances (n.m.r.) and a singlet at r 3-46 corresponding to the lone aromatic proton. In addition there appeared a doublet at r 4.08 (1 proton HA in VI; JAB= 2.5 c./sec.) a doublet at T 3-67(1 proton Hx; JBx= 10 c./sec.) and a quartet centred at T 3-21 (1 proton * The Robert Robinson Laboratories University of Liverpool. Manske “The Alkaloids,” ed. Manske Academic Press New York Vol. VI p. 423. Battersby Tilden Lecture Proc. Chem. SOC.,1963 189. (a) Barton and Cohen “Festschrift A. Stoll,” Birkhauser Basle 1957 p.117; (b) Erdtman and Wachtmeister ibid. p. 144: * Plieninger and Keilich Chem. Ber. 1958 91 1891 ;Gentles Moss Herzog and Herschberg J. Amer. Chem. SOC., 1958 80 3702 and foreshadowed in the ideas of Barton and Cohen ref. 3 (a). Gadamer and Klee Arch. Pharm. 1911 249 39; Neubauer and Mothes Planta Med. 1961 9 466. Tomira and Kunimoto J. Pharm. SOC.,Japan 1960 80 1238; Battersby Binks Francis McCaldin and Ramuz J. 1964 in the press. HB coupled to HA and Hx); JAx is approximately zero.’ These spectral data and the analytical values establish structure (11) for the product which corre- SPonds in structure to the new type of alkaloid recently isolated.‘ The dienone was reduced by bore-hydride to a mixture of two dienols which without separation was rearranged by acid.(f)-Isothebaine was isolated from the products (36% from the PROCEEDINGS dienone) and identified by comparison with the natmal alkaloid (infrared mass spectrometry and thin-layer chromatography). This synthesis gives support to the biosynthetic postulate and the appropriate tracer experiments on p. orientale are in progress. (Received January 30th 1964.) Cf. n.m.r. spectra of pronuciferine (Bernauer Helv. Chinz. Acra 1963,46 1783) and of crotonosine (Haynes Stuart Barton and Kirby Proc. Chern. Soc. 1963 280). Biosynthesis of Colchicine By A. R. BATTERSBY R. BINKS,and D. A. YEOWELL* THE non-equivalence of phenylalanine and tyrosine in the Amaryllidaceael allows earlier tracer results2s3 on colchicine to be rationalised in terms of ring A and carbon atoms 5 6 and 7 being derived from the phenylalanine-cinnamic acid pathway.We now out- line the decisive experiments to test this possibility and to determine the origin of the tropolone ring; supporting work will be described in our full paper. In the sequel figures in brackets after the name or formula number show the proportion of activity in that substance referred to the original colchicine as 1-00. [l -14C]Phenylalanine fed to Cokhicum autumnale plants afforded colchicine (1; R = Ac R’ = Me; 3-2% incorpn.) from which were derived the base (I; R = R’ = H; 1-04) and the anhydride (111; 0.05). Oxidation of the colchicine gave succinic acid (0.99) having all its activity in the carboxyl groups (Schmidt).At least 95 % of the activity of colchicine is thus located at position 7. Sodium [3-1*C]cin- namate similarly yielded colchicine (1 -0% incorpn.); the anhydride (111; 1-00) and the base (I; R = R = H; 1-00) were prepared from it. The colchicine obtained by feeding [2-14C]phenylalanine (0.58 % incorpn.) afforded the base (I; R = R’ = H; 1.01); further degradation has been deferred because Leete4 has shown incorporation of this precursor without randomisation. In contrast [1-14C]tyrosine is a poor precursor (6 x lo3% incorpn.) and degradation showed scatter of the label. When these results are combined with the earlier they firmly estab- lish the origin of ring A and carbons 5 6 and 7 from the phenylalanine-cinnamic acid pathway.Colchicine derived from plants fed with [3-14C]-tyrosine (0-7 % incorpn.) afforded the anhydride (111; 0-02) and by ozon~lysis,~ the acid (IV; 0.15). Hydrolysis of the latter gave acetic acid (0.13) and glutamic acid (0.02). Oxidation of colchicine yielded succinic acid (0.03). These results prove that posi- tions 12a and 7a of colchicine carry almost no activity. Rearrangement6 of the colchicine to allo- colchiceine (11; R = C0,H; 1-00) followed by de- carboxylation (CO corresponding to position 9 0.00) gave (11; R = H) which was oxidised to phthalic acid (0.81). Schmidt degradation gave anthranilic acid (0.81). These data prove heavy labelling of the tropolone ring system with carbons 7a 9 and 12a being almost inactive.The present interpretation is that ring c of colchicine is built by ring expansion of a c6-Cl unit derivable from tyrosine. It is suggested that a pre-cursor of type (V; R R’ R” = H or Me) undergoes phenoloxidation followed by ring expansion. (Received February 4th 1964.) * The Robert Robinson Laboratories University of Liverpool and The University Bristol. Wildman Battersby and Breuer J. Arner. Chem. Soc. 1962 84 4599; Battersby Binks Breuer Fales WiIdman and Highet J. 1964 in the press; Suhadulnik Fischer and Zulalian J. Arner. Chem. Soc. 1962 84 4348. Battersby and Reynolds Proc. Chem. SOC.,1960 346. * Leete and Nemeth .I. Amer. Chem. Soc. 1960 82 6055. Leete J. Arner. Chem. SOC.,1963 85 3666. Corrodi and Hardegger Helv. Chim. Acta 1955 38 2030.Fernholtz Annalen 1950 568 63. MARCH1964 Photoaddition of p-Quinones to Olefins :New Syntheses of Oxetans and Phenols By D. BRYCE-SMITH and A. GILBERT* WE report here a widely applicable photoaddition reaction of p-quinones to olefins the products are not the expected cyclobutanes but oxetans (cf. ref. l).? For example p-benzoquinone and cis-cyclo-octene readily gave the spiro-oxetan (I) and no detectable trace of compound (11) or other isomers (thin-layer chromatography). Structure (I) was de- duced from the n.m.r. spectrum (proton ratios 2 :2 :1:1:12) and from the quantitative acid-catalysed dienone-phenol rearrangement to com- pound (111) which was identical (m.p. mixed m.p. infrared spectrum) with material prepared inde-pendently by condensation of quinol and 3-bromo- cyclo-octene (cf.ref. 3). This rearrangement also occurred thermally at 20-1 50” but not photochem- ically under the conditions now used thereby differ- ing from the related rearrangement of the thermal adduct of diphenylketen and p-benz~quinone.~ The phenol (111) showed the expected resistance to cata- lytic hydrogenation but the adduct (I) consumed 1.0 mol. of hydrogen to givep-cyclo-octyloxyphenol(IV). The adduct (I) added thermally (but not photo- chemically) to anthracene to give compound (V) cyclopentadiene gave compound (VI). 1:1 Photo- adducts have been obtained from p-benzoquinone and cyclohexene cyclo-octa-l,5-diene cyclo-octa- tetraene bicycloheptadiene oct-1 -ene and oct-2-ene.These resembled the above adduct of cyclo- octene in their conversions into phenols and in their spectroscopic properties. The adduct of cyclo-octa- tetraene differed from the known thermal adduct and consumed 4 mol. of hydrogen on catalytic hydrogena- tion to give the phenol (IV). The adduct of cyclo- octa-1,5-diene consumed 2 mol. of hydrogen to give this same phenol. From n.m.r. evidence and per- acid titration the adduct of bicycloheptadiene con- tained one unconjugated ethylenic bond so was formed without rearrangement (cf. ref. 5). W Chloranil p-toluquinone and naphtha- lY4-quin- one readily gave 1 :1 photoadducts with cis-cyclo- octene and cyclo-octa-1 ,5-dieneY the i.r. and U.V. spectra of which showed the expected relationships to those of the corresponding adducts of p-benzo- quinone.The reactions occur readily in sunlight or with the use of a medium-pressure mercury arc lamp and a filter to absorb radiation of wavelength shorter than 280-290 mp benzene conveniently serves both as solvent and internal filter. Yields in the cases mentioned have generally exceeded 90% of theo-retical; but cyclo-octatetraene gave a 30 % yield. Satisfactory analyses and mass spectra have been obtained for the new compounds reported. (Received,January 14th 1964.) * Chemistry Department The University Reading. t In the light of this Hammond and Turro’s recent claim that cyclohexen-3-one “adds in a remarkably general manner to carbon<arbon double and triple bonds to form cyclobutanes” (and presumably cyclobutenes) is intriguing.2 Paterno and Chieffi Gazzetta 1909,39,341; Buchi Kofron Kollar and Rosenthal J.Amer. Chem. SOC.,1956,78,876. Hammond and Turro Science 1963 142 1541. ’’ Smith Ungnade Stevens and Cristman J. Amer. Chem. SOC.,1939 61 2615. Staudinger and Bereza Annalen 1911 380 243. Ullmann Chem. and Znd. 1958 1173; Cristol Allred and Wetzel J. Org. Chern. 1962 27 4058 and references therein. Structure of the Adducts of Triphenylphosphinimines with Acetylenedicarboxylic Ester By G. W. BROWN,R. C. COOKSON T. C. W. MAK and J. TROTTER* I. D. R. STEVENS TETRAPHENYLPHOSPHINIMINE (I; R = Ph) forms a rearrangement of C-C C-N or C-P bonds. Of the 1 :1 adduct m.p. 197-198” with dimethyl acetylene- two possible structures (I11 or IV) the latter seemed dicarboxylate.The isolation of aniline triphenyl- more compatible with the high dipole moment (5.3 D) phosphine oxide and the pyrazolone (11) from re- and with the ultraviolet spectrum (Amax. 274 mp action of the adduct with hydrazine excludes any E 10,600 with inflections at 222 and 313 mp * The Universityof Southampton(G.W.B. R.C.C.,and I.D.R.S.) and The Universityof British Columbia Vancouver 8 B.C. (T.C.W.M. and J.T.). PROCEEDINGS E 33,000 and 8300) which indeed is rather like that A perspective drawing of the molecule is shown in of (V)l (A,,, 266 and 318 mp E 8700 and 14,200). the Figure (the atom numbering is for convenience in the crystallographic analysis) from which it is The structure of the bromo-derivative (IV; R = p-C,H,Br) prepared from the phosphinimine (I; R evident that the structure is (IV; R = p-C,H,Br).= p-C,H,Br) was determined by X-ray analysis. 1. Br Crystals of the bromo-derivative are monoclinic with four molecules in a unit cell of dimensions a = 1 1-83 b = 9.24 c = 25-43A /3 = 104" 15' space group P2,/c. The intensities of 1940 reflections were measured with a scintillation counter and Mo-Ka radiation. The three-dimensional Patterson function indicated that the bromine atom was in a pseudo- special position and the structure was solved by determining the x-and z-co-ordinates from the b-axis projection and then deducing the y-para- meters by trials with various models. The para- meters were refined by three-dimensional F and (F -F,) syntheses differential syntheses and a cycle of least squares; R was then 0.21.C02Me Ph,P-NR Ph,P= '3. (1) NR H\N H wgJ=Lo2Me (a) (m Me0,C Ph"-ph C02Me W Analogous adducts (IV) are formed by other tri- phenylphosphinimines including the parent itself (I; R = H). They form salts (e.g. VI; X = H or Br Y = Br or ClO,) with acids or with bromine. Some phosphoranes such as the pentaphenyl compound add to dimethyl acetylenedicarboxylate to give similar yellow products (e.g. VII). (Received February loth 1964.) Snyder Cohen and Tapp J. Amer. Chem. Soc. 1939 61 3560. Model Compounds for Metal-Protein Interaction The Crystal Structure of Disodium Glycylglycylglycylglycinocuprate(1I) Decahydrate By H.C. FREEMAN and MAXR. TAYLOR* DISODIUM GLYCYLGLYCVLGLYCYLGLYCINOCUPRATE(II) glycylglycylglycine. The dihydrate reported earlier2 DECAHYDRATE has been prepared and its crystal could not be obtained by us. structure determined as part of a programme of Na,[C,H,,N4O,C~],l0H,O; Triclinic; a = 7.665 structure determinations of model compounds for b = 10.204 c = 14.872 A a = 93" 48',-/3 = metal-protein interacti0n.l The complex crystallised 107" 39' y = 94" 17'; 2 = 2. Space group PI. The in red needles from an alkaline solution containing intensities of 4319 unique reflections were recorded equimolar quantities of cupric hydroxide and glycyl- photographically with Cu-Koc radiation and esti- * School of Chemistry University of Sydney Sydney Australia; present address (M.R.T.) The Institute for Cancer Research 7701 Burholme Avenue Philadelphia 11 Pa.U.S.A. Cooper Freeman Robinson and Schoone Nature 1962 194 1237; Freeman Robinson and Schoone Acta Cryst. 1964 in the press; Freeman and Snow Acta Cryst. 1964 in the press; Freeman Schoone and Sime unpublished results. Rising Parker and Gaston J. Amer. Chem. Soc. 1934 56 1178. MARCH1964 mated visually; 629 intensities were too weak to be observed. The co-ordinates of the copper(I1) and 4 nitrogen atoms were obtained from a three-dimensional Patterson synthesis and those of the remaining atoms from 2 Fourier syntheses. Refine- ment by the full-matrix least-squares method with anisotropic temperature factors for all atoms has given a residual of 0.092 (hydrogen atoms omitted).The bond-length standard deviations calculated from the least-squares results are 0.004 8 for the Cu-N bonds and 0.007A for the light atom-light atom bonds. The crystal consists of layers of glycylglycylglycyl- glycinocuprate(n) anions ; these ions being stacked obliquely to the layers which are separated by layers of sodium ion-water molecule polyhedra. One glycylglycylglycylglycine molecule is co-ordinated to one copper(@ atom by way of its terminal amino-nitrogen atom and three peptide nitrogen atoms (Figure). The copper(@ atom is four- co-ordinate with the ligand nitrogen atoms in a distorted square-planar configuration. This distor- tion is probably due to strain which is caused by closing the three connected five-membered chelate rings.The hydrogen atoms formerly attached to the peptide nitrogen atoms N, N3 and N of the free peptide are ionised. This structure thus provides evidence from the solid state to support the deduc- tions made by Koltun Roth and Gurd3 concerning the source of the acid dissociations that occur in alkaline Cu2+-glycylglycylglycylglycine solutions. Bond lengths of the complex copper anion are shown in the Figure. These are in agreement with 01 4.267 I 02 The configuration and interatomic distances of the glycylglycylglycylglycinocuprate(iI) anion. (Distances are in Angstroms.) One sodium ion is surrounded by six water molecules and the other by five water molecules and one carboxyl oxygen atom.These octahedra share a face of water molecules. Water molecule protons are involved in extensive hydrogen bonding with the complex copper anion. those found for other metal-peptide c0mp1exes.l~~ Koltun Roth and Gurd J. Bid. Chern. 1963,238 124. Strandberg Lindqvist and Rosenstein 2.Krist.,1961 116 266. The Pentadehydrocorrin (Corrole) Ring System By A. W. JOHNSONand I. T. KAY* THE 1',8'-dideoxybiladiene-a~ (I) prepared by a method analogous to that described previously,l when irradiated in dilute basic methanolic solution by light from a 200 w tungsten bulb at a distance of 5 cm. rapidly (ca. 10 min.) cyclises to the corrole (11) C29H34N4, m.p. 255-257" in a yield of ca. 60 %. The crystalline corrole contains an aromatic (18 T-electrons) ring system and in chloroform solution has an absorption spectrum which contains an intense Soret band (Fig.).Treatment of the new macrocycle with dilute hydrobromic acid in acetone gave a crystalline mono- hydrobromide; under similar conditions porphyrins form dihydrobromides. However a solution in 400 (Received,January 6th 1964.) ,I 500 600 strong sulphuric acid (and to a lesser extent in tri- Wavelength (rnfi) fluoroacetic acid) showed a spectrum which con- Visible absorption spectra of 4,5-diethyl-l,2,3,6,7,8-tained a new band at 670mp but no Soret band and hexarnethyl-porphyrin (--) and -corrole. * Department of Chemistry University of Nottingham. Johnson and Kay J. 1961 2418. suggested that under these conditions the corrole was present as the tautomeric non-aromatic di-cation (111).This form reverted to the original corrole (11) on basification. Addition of dilute alkali to solutions of the corrole causes large spectral changes although with reten- tion of the Soret band because of the formation of the stable anion (IV). Previous work2 has emphasised the stability and ease of formation of analogues of (IV) which contain oxygen sulphur and imino- bridging groups in place of the bridging carbanion. The whole series therefore may be regarded as show- ing the same relation to the parent porphyrin ring system as do furan thiophen pyrrole and the cyclo- pentadienyl anion to benzene. Moderately stable crystalline nickel and zinc derivatives of the corrole have been prepared either by the addition of nickel or zinc cations to solutions of (11) or by the inclusion of nickel (but not zinc) ions before the irradiation of the biladiene-ac (I).Absence of the Soret band in the spectrum of the nickel complex suggests that it is derived from the non-aromatic base corresponding to (III) and in agreement with this view it is observed that addition of alkali to solutions of the nickel complex causes the reappearance of the Soret band in the spectrum cor- responding to the formation of the nickel complex Johnson Kay and Rodrigo J. 1963 2336. Closs and Closs J. Amer. Chem. SOC.,1963 85 818. PROCEEDINGS of the anion (IV). This change is reversed by acidi- fication. The ready formation of the corrole anions is in marked contrast to the behaviour of porphyrins3 and the contrast is emphasised further by the rapid exchange of all three rneso-protons of (11) for deuterium when solutions in deuterated trifluoro- acetic acid are examined by n.m.r.~pectroscopy.~ Me Me Me (a Me Me Me Et 42 Et (Received February 13th 1964.) Woodward and SkariC J. Amer. Chem. SOC.,1961 83,4676; Abraham Jackson and Kenner J. 1961 3468. NEWS AND ANNOUNCEMENTS The Corday-Morgan Medal and Prize.-The Council of the Chemical Society has awarded the Corday-Morgan Medal and Prize to Dr. N. Bartlett Associate Professor Department of Chemistry University of British Columbia in consideration of his prediction and discovery of the first stable com- pounds of an inert gas.The award is made in respect of the year 1962. This Award consisting of a Silver Medal and a monetary Prize is made annually to the chemist of either sex and of British Nationality who in the judgement of the Council of the Chemical Society has published during the year in question and in the immediately preceding five years the most meri- torious contribution to experimental chemistry and who has not at the date of publication attained the age of thirty-six years. If in the opinion of the Council two or more candidates are of equal merit a medal may be awarded to each and the prize divided equally among them. Copies of the rules governing the Award may be obtained from the General Secretary of the Society. Applications or recommendations in respect of the Award for the year 1963 must be received not later than December 31st 1964 and applications for the Award for 1964 are due before the end of 1965.Liaison Officers.-Dr. M. E. Trevett and Mr. E. J. H. Birch have been appointed Liaison Officers at the Colleges of Technology at Kingston-upon- Hull and Headington Oxford respectively. Mr. N. Ferry has been appointed Liaison Officer at Sunder- land Technical College in succession to Dr. W. R. Longworth who is to become Head of the Chemistry Department of the John Dalton College of Tech- nology Manchester. Local Representatives.-The Council has approved the following changes of Local Representatives Ceylon Exeter .. .. .. . . Dr. R.G. A. Rodrigo in place of Dr.R. 0.B. Wijesekera. Dr. R. J. Williams in place of Dr. J. S. Whitehurst. Liverpool .. Dr. C.F. H. Tipper in place of Dr. R. J. S. Beer. MARCH1964 Deaths.-We regret to announce the deaths of the following Dr. W. H. Glover (17.10.63) Box Wilts. formerly with Courtaulds Ltd. and Mr. W. Lowe (18.12.63) Nice a Fellow for 30 years. Election of New Fellows.-171 Candidates were elected to the Fellowship in February 1964. Scientists in the Public Service.-Dr. D. H. Whiflen is Deputy Chief Scientific Officer at the National Physical Laboratory and not at the National Chemical Laboratory as was stated in Proceedings 1964 p. 28. Royal Society Leverhulme Scholarships Tenable in Developing Countries.-The Council of the Royal Society is pleased to announce the establishment by means of a generous grant from the Leverhulme Trustees of scholarships to provide facilities for young graduates from the United Kingdom to gain practical experience of scientific problems in the developing countries.It is expected that about six of these scholarships which will be known as Royal Society Leverhulme Scholarships will be awarded annually during the next seven years. They will be of particular interest to graduates in the environmental sciences for which the developing countries pose numerous novel and challenging scientific problems. As these sciences have been founded largely upon conditions in north temperate regions it is evident that studies in areas south of the tropic of Cancer-where most of the developing countries lie-can add significantly to progress in these sciences as a whole.One of the objects of this new scholarship scheme is therefore to make the scholar aware at an early stage after graduation of the existence of scientific problems which he would not normally encounter in a laboratory in the United Kingdom. The scholarship would enable the scholar to collect data and if appropriate specimens which he could use in studies for a higher degree. The scholarships will normally be tenable for a period of 6 to 12 months and will cover the cost of travel to and within the country of choice as well as a maintenance allowance. Each scholar will be expected to work under the general direction of a senior scientist in the country to which he goes.This might be a professor in a university or a senior scientist in a government department or research institute or the leader of a recognised scientific expedition. The Council of the Royal Society has set up a committee to administer this scheme. Advertisements inviting applications will be made shortly. Open Days at the Laboratory of the Government Chemist.-The Laboratory of the Government Chemist is to hold its first Open Days in the new Cornwall House premises on April 22nd-23rd7 1964. Tickets to visit the Laboratory can be obtained from the Government Chemist Cornwall House Stamford Street London S.E.1. Applicants should state which day they would like to attend whether morning afternoon or all day.Symposia etc.-A Symposium on “Biosynthetic Pathways in Higher Plants” organised by the Plant Phenolics Group will be held at Leeds on April 13-15th 1964. Further enquiries should be ad- dressed to the Honorary Secretary A. H. Williams Research Station Long Ashton Bristol. A summer programme on “Thermodynamics A Unifying Science,” will be held in Massachusetts on June 29th-July 3rd 1964. Further enquiries should be addressed to the Summer Session Office Massa- chusetts Institute of Technology Cambridge Massachusetts U.S.A. A Symposium on Reactive Intermediates in Organic Chemistry (Nitrenes and Carbenes Free Radicals Carbonium Ions Carbonions) will be held in Quebec on August 27-29th 1964. Further en- quiries should be addressed to The Chemical Insti- tute of Canada 48 Rideau Street Ottawa 2 Ontario Canada.A Conference on Electron Emission will be held in Keele Staffs on October lst-2nd 1964. Further enquiries should be addressed to the Administration Assistant The Institute of Physics and The Physical Society 47 Belgrave Square London S.W.1. A Symposium on Bioenergetics sponsored by the Chemical Institute of Canada Biochemistry Divi- sion will be held in London Ontario on October 15-16th 1964. Further enquiries should be ad- dressed to The Chemical Institute of Canada 48 Rideau Street Ottawa 2 Ontario Canada. Personal.-Dr. M. P. Barnett Director at the Co- operative Computing Laboratory of the Massa-chusetts Institute of Technology is returning to London University to carry out a programme of research into the control of printing by computer.The Research is to be financed by a grant from D.S.I.R. The Council of the School of Pharmacy University of London have appointed Dr. 0.L. Brady an Honorary Fellow of the School in recognition of his many and considerable services to the school. Dr. E. J. ButZer has resigned from his post as Head of the Biochemistry Department Moredun Institute Edinburgh and has been appointed Uni- versity Lecturer in Biochemistry at Cambridge. D.S.I.R. have provided E17,175 to assist Professor J. I. G. Cadogan of the Department of Chemistry at The University of St. Andrews in his researches into the organic chemistry of phosphorus part of this sum to be used in the provision of facilities for nuclear magnetic resonance spectroscopy.A sum of E2,680 has also been provided to assist Dr. F. D. Gunstone in his investigation of the chemistry of seed oils. Professor J. W. Clark-Lewis who will attend the I.U.P.A.C. meeting in Japan in April will return to Australia via the U.S.A. and U.K. and will visit the C.S.I.R. Laboratories in Pretoria the University of Natal Pietermaritzburg and the Leather Industries’ Research Institute Grahamstown. The title of Fellow of University College London has been conferred on Professor D. P. Craig. A grant of &14,900has been made to Professor L. Crombie of University College Cardiff for the purchase of a nuclear magnetic resonance (n.m.r.) spectrometer required for research studies in organic chemistry.Professor C. Djerassi will be the guest of honour at the South African Chemical Institute Annual Convention in Pretoria in July 1964 and will after- wards visit the Universities of Natal Rhodes Stellenbosch and Cape Town. Mr. R. D. Gillard has been appointed Lecturer in Chemistry at the University of Sheffield. Dr. F. GZockling has been appointed Senior Lecturer in Chemistry at the University of Durham from October lst 1964. Dr. A. Goosen Senior Lecturer in the Department of Chemistry University of Natal Pietermaritzburg has returned to the University after spending a year with Professor D. H. R. Barton London. Sir Cyril HinsheZwood has been appointed to a Senior Research Fellowship at the Imperial College of Science and Technology from October 1964 on his retirement from the Dr.Lee’s Chair of Chemistry at Oxford University. Dr. Jennifer M. Hugo has been appointed to a post-doctoral Fellowship in the Natural Products Research Unit University of Natal. PROCEEDINGS The title of Honorary Fellow of University Col- lege London has been conferred on Sir Christopher Ingold. Dr. T. P. Jones formerly Research Fellow at the Royal Military College of Science has been ap- pointed Lecturer at the Welsh College of Advanced Technology Cardiff. Dr. J. W. Keyser Royal Infirmary Cardiff is Visiting Associate Professor of Chemistry in Medicine at the University of Pennsylvania until February 1965. Dr.A. R. Mattocks of the Toxicological Research Unit of Medical Research Council Carshalton will spend a year with Professor F. L. Warren in the Natural Products Research Unit University of Natal. Dr. G. K. Radda Junior Research Fellow has been elected to a Tutorship and Official Fellowship in Chemistry at Merton College Oxford from October lst 1964. Dr. P. W. Sadler is Head of Chemotherapy at the Lilly Research Laboratories Cheshire. Dr. S. H. Sharman has been appointed Group Supervisor of Surface Actives Section at the California Research Corporation San Francisco. Dr. G. Stedman has been appointed Senior Tutor of Neuadd Sibly at the University College of Swansea. Dr. R. H. Thomson has been appointed to the new Chair of Organic Chemistry in the University of Aberdeen.A grant of E8,300 has been awarded by the United Kingdom Atomic Energy Authority to support an investigation in the reactivity of irradiated carbons carried out under the direction of Professor Wynne- Jones at the Department of Chemistry University of Newcas t le . INTERNATIONAL SYMPOSIUM ON ORGANIC REACTION MECHANISMS CONTRIBUTIONS by the following authors will be presented at the symposium to be held in Cork from July 20th to 25th 1964 under the joint sponsorship of the Chemical Society the Institute of Chemistry of Ireland and University College Cork Lectures Professor H. B. Henbest Queen’s University of Belfast. Dr. R. F. Hudson Cyanamid European Research Institute Geneva Switzerland. Professor R.Huisgen University of Munich Germany. Dr. G. A. Olah Dow Chemical of Canada Ltd. Sarnia Canada. Professor 0. A. Reutov Lomonosov Moscow University U.S.S.R. Dr. W. A. Waters University of Oxford. Professor S. Winstein University of California Los Angeles U.S.A. Contributed Papers Dr. M. Anteunis State University of Ghent Belgium. MARCH1964 Professor E. M. Arnett University of Pittsburgh U.S.A. Professor S. Asperger University of Zagreb Yugoslavia. Dr. B. M. Benjamin Oak Ridge National Labora- tory Tennessee USA. Dr. K. Bowden Royal College of Advanced Tech- nology Salford. Professor A. E. Brodsky Ukrainian Academy of Science Kiev U.S.S.R. Professor J. I. G. Cadogan University of St. Andrews.Professor N. B. Chapman The University Hull. Professor R. J. Crawford University of Alberta Canada. Professor S. Cristol University of Colorado U.S.A. Professor P. B. D. de la Mare Bedford College London. Professor C. H. de Puy Iowa State University U.S.A. Professor J. E. Dubois University of Paris France. Professor C. Eaborn University of Sussex. Professor A. Fava University of Perugia Italy. Professor G. Fodor The Hungarian Academy of Sciences Budapest. Dr. V. Franzen Max Planck Institut Heidelberg Germany. Dr. H. R. Gersmann Koninklijke Shell Laboratory Amsterdam The Netherlands. Dr. V. Gold King’s College London. Professor M. J. Goldstein Cornell University U.S.A. Professor C. A. Grob Basle University Switzerland.Professor R. N. Haszeldine University of Man- Chester. Professor G. Illuminati University of Rome Italy. Dr. G. Kohnstam University of Durham. Professor E. C. Kooyman State University of Leiden The Netherlands. Professor S. R. Landor University College of Sierra Leone Freetown. Professor J. E. Leffler Florida State University U.S.A. Professor R. Levine University of Pittsburgh U.S.A. Professor A. Maccoll University College London. Dr. G. Markl University of Wurzburg Germany. Professor J. Michalski Technical University of Lodz Poland. Professor J. Miller University of Hong Kong. Professor G. Modena University of Bari Italy. Dr. M. J. Molera Institute of Physical Chemistry Madrid Spain. Dr. R. W. Murray Bell Telephone Laboratories Murray Hill U.S.A.Professor C. D. Nenitzescu Academy of the R.P.R. Bucharest Rumania. Dr. D. C. Nonhebel The Royal College of Science and Technology Glasgow. Professor R. 0. C. Norman The University York. Dr. A. Queen Laurentian University of Sudbury Canada. Professor G. A. Razuvaev Gorky State University U.S.S.R. Dr. R. E. Robertson National Research Council Ottawa Canada. Dr. C. Ruchardt University of Munich Germany. Professor D. Samuel The Weizmann Institute of Science Rehovoth Israel. Professor S. Sarel The Hebrew University Jerusalem Israel. Dr. J. P. Schaefer University of Arizona U.S.A. Dr. F. Scheinmann Royal College of Advanced Technology Salford. Doz. Dr. U. Schollkopf University of Heidelberg Germany.Professor F. L. Scott University College Cork. Professor E. A. Shilov Kiev U.S.S.R. Professor H. J. Shine Texas Technological College U.S.A. Professor J. Sicher Czechoslovak Academy of Science Prague Czechoslovakia. Professor M. Simonetta University of Milan Italy. Dr. A. Smoczkiewiczowa University of Poznan Poland. Professor J. E. Stille State University of Iowa U.S.A. Dr. C. M. Stirling Queen’s University of Belfast. Professor E. Tommila University of Helsinki Finland. Professor A. F. Trotman-Dickenson University College of Wales Aberystwyth. Professor C. Walling Columbia University U.S.A. Professor A. Wassermann University College London. Professor H. Zollinger Swiss Federal Institute of Technology Zurich Switzerland.Dr. P. Zuman Polarographic Institute Prague Czechoslovakia. The programme is now complete and additional requests to contribute a paper to the meeting cannot be considered. Those who have already expressed an interest in the meeting will receive full particulars and a registra- tion form early in May 1964. Others who are interested should apply to the General Secretary for particulars without delay since it will be difficult to offer accommodation in Cork to those who apply after April 10th. Intending participants should note that the programme has now been extended by the inclusion of an additional session on the morning of Saturday July 25th. PROCEEDINGS FORTHCOMING SCIENTIFIC MEETINGS London Thursday May 7th 1964 at 6 p.m.A Discussion on Mass Spectrometry will take place in the Rooms of the Society Burlington House W. 1. The following papers will be presented “Instrumentation and General Applications of Mass Spectrometry,” by Dr. J. Beynon. “Specific Examples of the Use of Mass Spectro- metry in Organic Chemistry,” by Dr. R. I. Reed. (Abstracts of the Papers can be obtained from the General Secretary.) [British Railways are offering concessionary fares (single fare plus one half for the return journey) for this meeting and a travel voucher will be sent by the General Secretary on receipt of a stamped and addressed envelope.] Birmingham Friday May 8th 1964 at 4.30 p.m. Lecture “The Scientific Examination of Questioned Documents,” by Professor C.L. Wilson Ph.D. D.Sc. F.R.I.C. Joint Meeting with the University Chemical Society to be held in the Chemistry Department The University. Cardiff Monday April 27th 1964 at 5 p.m. Tilden Lecture,“A Glow in the Dark-The Rationale of Phosphorylation,” by Dr. V. M. Clark M.A. To be given in the Department of Chemistry University College Cathays Park Cardiff. Dublin Wednesday April 22nd 1964 at 5.30 p.m. Lecture “Polycomponent Liquid Crystals and Their Place in Living Matter,” by Dr. A. S. C. Lawrence F.R.I.C. To be given in the Department of Chem- istry University College. Exeter Friday April 24th 1964 at 4.15 p.m. Lecture “Chemical Control Mechanisms of Meta-bolism,” by Sir Hans Krebs M.D. F.R.S. To be given in the Department of Chemistry The Uni- versity.Keele Monday April 27th 1964 at 5 p.m. Lecture “Sex Hormones,” by Professor A. J. Birch D.Phil. F.R.S. Joint Meeting with the University Chemical Society to be held in the Department of Chemistry The University. Manchester Thursday April 23rd 1964 at 10 a.m. Symposium “Chemicals in the Service of Petrol- eum.” Joint Meeting with the Institute of Petroleum the Society of Chemical Industry and the Royal Institute of Chemistry. To be held in the R/C2 Renold Building Manchester College of Science and Technology. Norwich Thursday April 30th 1964 at 5.30 p.m. Lecture “Claudogenic Steroids,” by Dr. V. Petrow F.T.I.C. To be given in Lecture Room 2 The University of East Anglia Wilberforce Road.St. Andrew Thursday April 23rd 1964 at 5.15 p.m. Lecture to be given by Professor B. Lythgoe M.A. Ph.D. F.R.S. Joint Meeting with the University Chemical Society to be held in the Chemistry Department St. Salvator’s College. Tees-side Wednesday April lst 1964 at 8 p.m. Lecture “The Scientific Examination of Anti-quities,” by Dr. A. E. Werner. To be given at the Vane Arms Hotel High Street Stockton-on-Tees. OBITUARY NOTICES BERTRAM LAMBERT 188 1-1 963 DR.BERTRAM was born in Settle Yorks LAMBERT in 1881 the son of James Wilcock Lambert printer and died on July lst 1963. He attended Giggleswick School and from there won an exhibition to Merton College Oxford to read Chemistry obtaining a First Class Honours degree in 1903.The head of the Chemistry Department Professor Odling at once appointed him a demonstrator in the laboratory. At that time the department was lacking in any tradition of original research and facilities available were very meagre. Lambert however on his own initiative began a series of experimental studies on MARCH1964 the rusting of iron. These involved the carefully planned preparation of iron water and oxygen of exceedingly high purity. To achieve this he made himself by constant practice into a skilled glass- blower; this practice continued so that in later life he was considered the best amateur glassblower in the country. The conclusion he drew from the results of these researches published in the Journal for 1912 was that rusting was electrolytic in nature.This correct deduction had to remain for several years before it was verified and became generally accepted. Lambert’s work at this stage was inter- rupted by the First World War which he entered as an officer in the Royal Engineers. It was then that he was able to seize an opportunity of importance. After the first gas attack on front-line trenches by the Germans the Army set up a defence organisation and hasty trials were made of various forms of protection. Lambert while on a short leave himself constructed a box-type respirator with granules of soda-lime treated with permanganate and contacted the new organisation. As the result of tests Lambert’s device was adopted and respirators containing such granules were used throughout the war.For this contribution he was later awarded the O.B.E. and a substantial grant of money. After the war Lambert returned to the laboratory in Oxford and was elected to a tutorial Fellowship at Merton College. He then commenced a series of researches on the adsorption of gases by solids particularly in the system palladium-hydrogen and systems of silica and ferric oxide gels with various gases. Remarkable hysteresis effects were observed different equilibrium pressures being found depend- ing on whether the solids were taking up or liberating gas. This work was followed by a study of chemical methods of gas analysis and the development of an apparatus capable of achieving an accuracy of 0.02% on a gas sample of only 10 cc.All these experiments were carried out in elaborate glass apparatus entirely constructed by Lambert with the blowpipe. His laboratory methods were those of careful and logical planning meticulous attention to detail and a strict insistence on accuracy. These conditions always took precedence over the rapid production of results and he seemed at least as much concerned with the soundness of technique as with the final signiiicance of the measurements. He was an excellent supervisor of students and a good judge of ability and character. After the retirement of Professor Soddy Lambert acted as administrative head of the department and took a full part in University business. His straight- forward friendly and commonsense manner in all his dealings was a constant source of strength in the Oxford school of Chemistry.He was a good cricketer when young and later played golf and bowls with skill and enthusiasm. Happily married in 1908 to Sylvia Dewe his family consists of a son James Dewe Lambert now Fellow of Trinity College and University Lecturer in Chemistry at Oxford and a daughter now Mrs. Broad. He retired from his University posts at the age of 67 and until his death lived quietly in the city where he had spent his working life. E. J. BOWEN. BRIAN ERNEST BETTS 1934-BRIANERNESTBETTS was educated at the Mid-Essex Technical College Chelmsford and at The Polytechnic Regent Street W.l gaining both B.Sc. General and Special Chemistry degrees as an external student of the University of London.He joined my research group as Research Assistant in September 1956 and worked on addition and exchange reactions of acetone cyanhydrin gaining the Ph.D. degree in 1960. During the period of research he acted as a part-time lecturer and showed the capacity for clear expression of ideas and a kind- ness and consideration for his students which became characteristic of his work. He was very popular with all his students and the whole of the Staff of the Department welcomed him as a full-time colleague in May 1960 In September 1961 he was given a year’s leave of 1963 absence to take up a post-doctoral Fellowship in the Department of Chemistry and Chemical Engineering University of Illinois U.S.A.where his efforts were of such promise that he was invited to remain for a second year. He returned to The Polytechnic in September 1962 and eagerly took up both teaching and research where he had left off. Up to the time of his death he was busily engaged in designing apparatus for a research student who was to have started work with him. His death leaves a real gap in the ranks of pro- mising young organic chemists with a real flair for both teaching and research. His colleagues and his students will miss a kind and generous friend. W.DAVEY. PROCEEDINGS ARTHUR THURLBY DANN 1905-1 962 ARTHUR DANNwas born on August 5th, THURLBY 1905 at Castlemaine Victoria and died on December 16th 1962. He was dux of the Castlemaine High School won a Government Scholarship and studied science at the University of Melbourne.He was one of the best students of the Chemistry I11 class and won the Dickson Research Scholarship on graduating B.Sc.in 1927. This was followed a year later by the M.Sc. which at that time was awarded largely on the results of written examinations. However Dann was awarded the infrequently available Wyselaskie Research Scholarship which enabled him to devote his fifth year to full-time original research which became his life occupation. He collaborated with the writer then a newcomer to Melbourne in studying the transmission of the activating effect of the nitro-group through styrene systems in u- rn- and p-substituted w-halogeno- styrenes,’ and also the conversion by hydrazine hydrate of o-nitrosulphonyl chlorides of the benzene series to the corresponding sulphinic acids.2 Further aromatic work followed and as Dann had proved himself an excellent research chemist with a flair for quantitative analysis he was in 1929 offered a posi- tion with the C.S.I.R.He had not studied biochem- istry but rapidly learnt the main current biochemical techniques by taking a short experimental course specially provided for him by the Biochemistry Department under Professor W. J. Young. His first investigations with C.S.T.R. were on the diseases of cattle and he was the chemist in teams studying Enzootic Haematuria3 and Pegleg in ~attle.~ During 1935-1937 he worked on immuno- chemistry at the Lister Institute with W.T. I. Morgan and also took the Pregl course in quantita- tive microanalysis at Graz. On his return to Australia he became established and remained in the C.S.I.R. Animal Health Research Laboratory at Parkville Me1 bourne. His research interests covered a wide field first on the antigenic structure of specific micro-organisms and then haematuria which involved an extension of the earlier work on the chemical composition of the urine of COWS,^ and the relationship of the diet to the problem of spontaneous internal diseases in J. Chem. SOC.,1928 605. J. Chem. Soc. 1929 1050. Cf. C.S.I.R. Pamphlet No. 33 1932. Journal of C.S.I.R. 1935 8 120. Aust. J. Experimental Biol. and Med. Sci.,1933 11 53.Nature 1962 195 570. ’Nature 1963 197 207. animals. It seemed possible that bovine haernaturia and “dye-worker’s cancer” (Le. of the bladder) had a similar etiology and preliminary work with Dr. L. B. Bull and Dr. A. W. Turner was done on mice by inserting in the bladder wall a pellet containing a metabolite such as 3-hydroxykynurenine. It was shown that mice on a diet difficient in the Vitamin B complex tended to show hyperplasia and metaplasia irrespective of the type of pellet while those on normal diets showed these changes less frequently and less severely. This threw light on the fact that the syntheses of the ruminal micro-organisms in cattle and sheep do not make them completely independent of outside sources for their vitamin intake and hence for their health and growth.Dann’s abiding interest in this topic of the relationship of diet to disease led him to consider the hepatotoxic properties of pyrrolizidine alkaloids. With Drs. C. C. J. Culvenor and A. T. Dick6 he points out the resemblance between these alkaloids and the synthetic biological alkylating agents in their effects on cell nuclei both groups giving rise to muta- genesis chromosome breakage and carcinogenesis. They have shown that these alkaloids can react chemically as alkylating agents by a mechanism of alkyl-oxygen fission and they suggest that the hepato-toxicity is due to an esterified allylic amino- alcohol group. This indication that plant products can contain biological alkylating agents is likely to have important results on the study of animal and human cancer.The question of the detoxification of the above alkaloids in rumen liquor has also been approached by Dann and associated workers.’ Though Dann was a very keen and energetic scientist he only published some eleven papers. He spent much time in synthesising many of the complex metabolities and other biological products used for animal testing and was unsparing in the help he as a chemist and mathematician gave to his biologically trained colleagues. He was very interested in photo- graphy hiking and music and was of a retiring self-effacing disposition and remained single though his kindly nature endeared him to the children of his numerous friends. W. DAVIES.MARCH1964 EDWARD DAVID HUGHES 1906-1 963 E. D. HUGHES was born at Criccieth on June 18th 1906 of a farming family. His first degree in chem- istry was taken at the University College of North Wales at Bangor under the guidance and inspira- tion of Professor K. J. P. Orton and his first research work was done with H. B. Watson. In 1930 he took the degree of Ph.D. of the University of Wales and in that year joined Professor C. K. Ingold in the Chemistry Department of University College London as a post-doctoral Fellow. In 1936 he became Ramsay Memorial Fellow and then succes- sively Assistant Lecturer and Lecturer on the staff of that Department. Through the war years he carried a heavy share of the departmental teaching load during the period of evacuation to Aberystwyth.In 1943 he returned to the University College of North Wales where as Professor of Chemistry he was responsible for the rapid post-war expansion and re- building of his Department. In 1948 he was appointed Professor of Chemistry at University College London and in 1949 he was elected to Fellowship of the Royal Society. In 1961 he became Head of the Chemistry Department and Director of the William Ramsay and Ralph Forster Laboratories at Univer- sity College London; he died in University College Hospital on June 30th 1963 after a short illness. He is survived by his wife Ray Fortune Christine daughter of the Rev. L1. Davies of Brecon whom he married in 1934 and by their daughter. Throughout his scientific life Hughes was associated with the mechanistic approach to chem- istry and it would require a review of great length to put all his contributions into proper historical and scientific perspective.His work was illuminated throughout by his breadth of outlook. He always sought to isolate in as simple a form as possible the elementary individual steps involved in the reactions under study; and at the same time to draw the widest possible analogies between the common character- istics of different chemical processes. He recognised at a very early stage that the details of chemical bonding in the transition state are important for organic chemistry and can be approached by the powerful kinetic method which gives information concerning the initial and transition state differenti- ally.From this approach sprang for example the Hughes-Ingold theory of environmental effects,l which in principle is applicable to all single stage processes. From it sprang also the realisation that in bimolecular reactions the electronic requirements of bond-formation and bond-breaking are often in opposition;his clear appreciation of the consequences J. 1935 244. J. 1933 69. Nature 1933 132 933. of this led him to reject over-simplifications in con- sidering the effect of structure on reactivity. Another feature of his approach important in most of his major researches involved a recognition of situa- tions where more than one mechanism is available for a single overall chemical transformation.He was also a major pioneer in developing the use of isotopes for chemical studies. Collaborating first with C. L. Wilson and with J. N. E. Day and later with J. Dostrovsky D. R. Llewellyn and C. A. Bunton he was responsible for establishing practic- able methods for separation and concentration of deuterium and of isotopic oxygen. He used these isotopes for elegantly conceived and brilliantly exe- cuted investigations; not only in tracing of unusual reaction paths but also for the simplification of theoretical treatment by examination of reactions which are symmetrical chemically but unsym-metrical isotopically. His first researches at University College London with C. K. Tngold established a collaboration which was maintained throughout the remainder of his life.Elimination reactions were first considered,2 and through some 28 papers the concept was developed that two main mechanisms determine the comple- mentary interlocking patterns of reactivity and product-composition. Environmental and constitu- tional including steric and stereochemical effects were studied; and the derived ideas had wide implica- tions particularly for the concomitant reaction of nucleophilic replacement. Study of this starting from the viewpoint of duality of me~hanism,~ was developed in more than 100 publications. The classical and long-puzzling problem of the Walden inversion was absorbed into the framework of theoretical chemistry through the elucidation of the main factors determining whether racemisation re- tention or inversion of configuration accompanies nucleophilic substitution at a saturated carbon atom.Particularly important in this connection and not yet fully treated theoretically was the experimental verification that the transition state for bimolecular displacement at tetrahedral carbon has its shape determined primarily by covalent rather than by electrostatic bonding force^.^ The discovery that the carboxylate-ion substituent can interact with a developing carbonium ionic centre and thus can control its reactions and stereochemistry> led to the recognition of the wide range of substituents that can act as “neighbouring groups.” Through the rational application of these principles the way was paved for the determination of relative configura- J.1937 1252. Nature 1936 138 759; J. 1937 1208. tions at optically active centres including those of the conventional standards serine and glyceralde- hyde.6 Several other important issues developed from his interest in nucleophilic replacements particularly through clarification that mechanistic studies have brought to our understanding of anionotropic re- arrangements. Having independently proposed on theoretical grounds that bimolecular substitution with anionotropic rearrangement should exist,’ Hughes devised an isotopic tracer method for estab- lishing its likely field of application and in associa- tion with B. D. England brought this to a successful experimental conclusion.* Rapid development of knowledge concerning this mode of reaction has followed in consequence.He also made elegant studies of Wagner-Meerwein rearrangements par- ticularly those occurring in aliphatic systems. He and Dostrovsky clarified the mystery surrounding the chemistry of neopentyl halides by showing that their special lack of reactivity is determined by steric hindrance and thus is confined to bimolecular re- actions; and that the unimolecular reactions of these compounds lead to rearranged products. Re-examination of the classical bicyclic systems9 led further to the introduction of the term “synartesis” to describe enhancement of heterolytic reactivity derived from the bridging of carbonium ionic centres by split single bonds.So far we have been concerned primarily with reactions in which the organic substrate is involved in reaction with a nucleophile; but Hughes’ contri- butions to the converse type of reaction in which an electrophile is concerned were equally profound and far-ranging. His first papers in this field indeed were those of his early researches with H. B. Watson on the ionisation mechanism of prototropy particularly as studied by halogenation.1° He returned to investi- gations on prototropy many years later when with Ossorioll he established by an isotopic tracer tech- nique the availability of the synchronous termole- cular path for prototropic rearrangement in the methyleneazomethine system. Theoretical contribu- tions concerning the effect of structure on rates12 and equilibria13 in prototropic systems reveal yet again his broad perception of the generalisations which help to inter-relate patterns of reactivity throughout the field of heterolytic processes.Early work on aromatic substitution with Nature 1950 166 178. ’Trans. Faruday Soc. 1938 34 194. Nature 1951 168 1002. Nature 1951 168 65. loJ. 1929 1945; 1930 1733; 1931 3318. l1 J. 1952 426. l2 Nature 1941 147 81. l3 J. 1948 17. l4 J. 1935 1607; 1937 202. PROCEEDINGS Anantakrishnan and with Le Fevre14 led to his association with Ingold in a general attack on the mechanism of nitration. This brilliant work cul- minated in the establishment that the nitronium ion is the most important electrophile concerned in this rea~ti0n.l~ Extension to N-nitration and to O-nitra- tion followed,16 and he inspired the search for proof that other electrophilic substitutions can involve positively charged species.Notable contributions resulted in the fields of halogenation1’ and of C-and of N-nitrosationl* where it was also established that formally neutral electrophiles are implicated in attack on the aromatic nucleus more commonly than is the case for nitration. Homolytic substitutions in the side-chain of t-butylbenzene also received atten- tion.19 Investigation of aromatic substitution led directly to Hughes’ deep interest in aromatic rearrangements. In 195120 he proposed and discussed the evidence that the conversion of arylhydroxylamines to amino- phenols is normally anionotropic in character in- volving external movement of the migrating group.The rearrangement of N-to C-nitroamines con- sidered at about the same time was shown to be intramolecular ;21 and isotopic tracer methods were used in later researches to elaborate this view. The benzidine rearrangement presents quite different problems and was still under study at the time of Hughes’ death. Early discussions22 have required amplification and modification as the result of later studies in collaboration with Ingold and Banthorpe ; the recent series of papers in this field some of which are to be published posthumously complete a major contribution to knowledge of this reaction. It is shown that several mechanisms must be taken into account in any general interpretation of the pattern of product-formation ; these are similar in general character but have different consequences for the product-forming steps because of differences in details of the electronic distribution in the migrating fragments.Of the studies recently initiated by Hughes prob- ably none has more far-reaching implications for chemical advance than his research with Ingold Charman and others on electrophilic substitution at a saturated carbon atom. As for the converse case in which a nucleophile is involved the stereochem- istry of the transition state was the starting point. Following the technical triumph of obtaining for the l5 Nature 1946 158 448 480. l6 Nature 1952 170 972.l7 Research 1950 3 192. Is Nature 1950 166 642. l9 J. 1959 2734 2741. 2o Nature 1951 168 909. 21 J. 1950 2678. 22 J. 1941 608. MARCH1964 first time optical activity from a single asymmetric metal-bearing carbon atom by the resolution of s-butylmercuric the various reaction paths for mercury-exchange were delineated and studied by using the technique of isotopic labelling. Bimolecular processes of various kinds occurring with complete retention of configuration were recognised ; further research in this field is still in progress and important posthumous papers can be expected. The breadth of Hughes’ outlook and the value of treating chemistry as one subject not arbitrarily to be divided into its separate sections even at the frontiers of progress is witnessed by consideration of his substantial contributions to inorganic chemistry.His first studies of this kind were made with 0. L. brad^,^^ and concerned the metal complexes of 2,2’-dihydroxybiphenyl where the non-coplanar chelate ring is of the unusual 7-membered type. There followed an important discussion25 of the pro- cesses of ionisation accessible in liquid sulphur dioxide. Jander’s theory of oxide-ion transfers which currently had received wide credance was shown to be wholly incorrect. The work on nitration with the brilliant collaboration of Millen Gold Gillespie Goddard Reed G. H. Williams and others led to further developments in inorganic chemistry through the proper characterisation of covalent nitronium compounds and the isolation of a new range of stable ionic compounds the nitronium salts.Following this lead Hughes inspired a search for the halogen cations and this led to eviden~el~~~~ that two independent only slowly interconvertible positively charged sources of electrophilic chlorine can co-exist in aqueous solution. Alongside the development of his own enthusiasms Hughes maintained a policy of encouraging and furthering independence in his younger colleagues and associates. Many of these are now in distin- guished positions both in Great Britain and abroad and owe a great debt to him for his generosity and faith in their ability and promise as do all who benefitted from his advice and his example.The William Ramsay and Ralph Forster Laboratories developed a rather special spirit of unselfish col- laboration in furthering the advancement of know- ledge and in this way the names of Hughes and Ingold became inextricably linked through their long and unique association. It is inevitable in such cir- cumstances that the question of their individual con- tributions should occasionally be a matter of specu- lation ;but the pattern of their publications indicates clearly that both have intended their combined work to be thought of as a unity within which each has played an independent and distinctive part. Hughes made many contributions both direct and 23 Chem. and Ind. 1958 1517. f4 J. 1933 1227. indirect to the teaching of chemistry.He wrote many timely and enduring review articles the most famous perhaps being those of the Faraday Society Discussions of 1937 and 1941. All of them were characterised by clarity of style emphasis on general principles and far-sighted predictions of the lines of future advance. In 1961 he undertook for Elsevier the editorship of a series of monographs on Reaction Mechanisms in Organic Chemistry two volumes of which have now appeared; this series should fill an important gap in chemical literature. He was a valued teacher and colleague both at Bangor and at University College London where he was Dean of the Faculty of Science from 1958 until 1961. As an Appointed Teacher of the University of London he became Chairman (1955-60) of the University Board of Studies in Chemistry where his wise and efficient conduct of business won him many friends; his guidance and commonsense will be much missed in the years of change ahead.He was greatly in demand as an external examiner for first degrees and for higher degrees of Universities throughout the country. He performed an important task as Honor- ary Secretary (1949-61) and then as Chairman of the Advisory Council of the Ramsay Memorial Trust. On committees of selection for I.C.I. Ltd. and other senior research fellowships and indeed also for senior appointments generally his judgment and powers of assessment were regarded highly. Outside the University he played many valuable roles. He was a Governor of the Northern Poly- technic (1950-60).He was a Fellow (1938) and Member of the Council (196143) of the Royal Institute of Chemistry and acted for the Institute as Assessor in Organic Chemistry for Higher National Certificates and Diplomas and as a special examiner; he was honoured by the Institute as Meldola Medal- list in 1936. To the Chemical Society he contributed personally in a multitude of ways; not only by his many scientific publications and by his participation in symposia and discussions but also by serving unselfishly on its sub-committees. He was Chairman of the Library Committee from 1959 onwards; an Honorary Secretary of the Society from 1950 to 1956 and a Vice-president from 1956 to 1959. From 1953 to 1955 he was Honorary Secretary of the Chemical Council; and he was a member of the organising committee for the very successful XIXth Meeting of the International Union of Pure and Applied Chemistry.Hughes had a dry humour and a sense of occasion which made him an excellent after-dinner speaker. He had a real understanding of human nature and a sympathy and respect for individuals which showed itself in his relationships with his friends and col- 26 J. 1944 243. 26 J. 1954 1290. leagues and was marked by the extent to which his advice was sought on difficulties of all kinds. His patience directness and recognition of general prin- ciples led him to the heart of whatever problem was under consideration. He had a clear understanding of the nature quality and extent of personal responsibility at all levels; a sense of personal example; a deep and abiding feeling of loyalty; and a devotion to the Department where so much of his work was done.No historian in attempting to assess the contribu-tion made by Hughes to the advancement of know-ledge should forget the context within which his work developed. At the beginning of his career the concept that carbonium ions were reactive inter- mediates important in organic chemistry was not recognised ;and the usefulness of considering organic reactions in terms of unstable intermediates and the transition states which lead to them was not appreci- ated. Throughout his life Hughes in the face not only of formidable opposition to his whole approach but also of repeated bitter and often unjustified criticism on points of detail and of priority showed a steadfast belief in the importance of this new approach to chemistry; an insistence on the neces- sity of putting each new point as it came under scrutiny on a firm experimental basis; and an intui- tive recognition of the quality of key observations and of the nature of the crucial experiments which might lead to them.He leaves behind him an organic chemistry which is a vindication of his outlook; re- shaped rationally based on sound physical theory and capable of development in many directions on the lines of which he was one of the great pioneers and champions. He leaves behind him also many who will remember him as a man of vision of integrity and of humanity.P. B. D. DE LA MARE. ADDITIONS TO THE LIBRARY Tables of spectrophotometric absorption data of compounds used for the colorimetric determination of elements. Pp. 626. Butterworths. London. 1963. Tables of experimental dipole moments. A. L. McClellan. Pp. 713. W. H. Freeman & Co. San Francisco. 1963. (Presented by the publisher.) Liquid-liquid equilibriums. A. W. Francis. Pp. 288. Interscience. New York. 1963. Molecular rearrangements. Edited by P. de Mayo. Part 1. Pp. 706. Interscience. New York. 1963. Physics and chemistry of the organic solid states. Edited by D. Fox M. M. Labes and A. Weissberger. Vol. 1. Pp. 823. Interscience. New York. 1963. Rates and equilibria of organic reactions as treated by statistical thermodynamic and extrathermodynamic methods.J. E. Leffler and E. Grunwald. Pp. 458. J. Wiley and Sons. New York. 1963. High polymers structure and physical properties. M. Gordon. Pp. 158. Iliffe Books Ltd. for the Plastics Institute. London. 1963. Inorganic complexes. C. K. Jnrrgensen. Pp. 220. Academic Press. London. 1963. Chemistry of the lanthanides. T. Moeller. Pp. 117. Reinhold. New York. 1963. Water and its impurities. T. R. Camp. Pp. 355. Reinhold. New York. 1963. Treatise on analytical chemistry. Edited by I. M. Kolthoff and P. J. Elving. Part 1 vol. 4. Pp. 1751-2705. Interscience. New York. 1963. Theorie und praxis der gravimetrischen Analyse. Vol. 1. L. Erdey. Pp. 382. Akademiai Kiado. Budapest. 1964. (Presented by the publisher.) Thin-layer chromatography.J. M. Bobbitt. Pp. 208. Reinhold. New York. 1963. Compilationof gas chromatographic data. Prepared by J. S. Lewis. Sponsored by ASTM Committee E-19 on Gas Chromatography. (ASTM Special Technical Publica- tion no. 343.) Pp. 625. ASTM. Philadelphia. 1963. Complexation in analytical chemistry a guide for the critical selection of analytical methods based on com- plexation reactions. A. Ringbom. (Chemical Analysis- Vol. 16.) Pp. 395. Interscience. New York. 1963. Modern methods of analysis of copper and its alloys. C. M.Dezinel. 2ndedn. Pp. 287. Elsevier. Amsterdam. 1963. Quantitative analysis of drugs. D. C. Garratt. 3rd edn. Pp. 925. Chapman and Hall. London. 1964. Standard methods of the Oils and Fats Division of the I.U.P.A.C.5th edn. Butterworths. London. 1964. Quantitative chemical techniques of histo- and cyto- chemistry. D. Glick. Vol. 2. Pp. 513. Interscience. New York. 1963. Biosynthesis of vitamins and related compounds. T. W. Goodwin. Pp. 366. Academic Press. London. 1963. Recent advances in food science. Edited by J. M. Leitch and D. N. Rhodes. Vol. 3. Pp. 325. Butterworths. London. 1963. Handbook of cosmetic science an introduction to principles and applications. Edited by H. W. Hibbott in association with the Society of Cosmetic Chemists of Great Britain. Pp. 556. Pergamon Press. Oxford. 1963. Textbook of photographic chemistry. D. H. 0. John and G. T. J. Field. Pp. 330. Chapman and Hall. London. 1963. Mathematical methods in chemical engineering.V. G. Jenson and G. V. Jeffreys. Pp. 556. Academic Press. London. 1963. An introduction to clay colloid chemistry for clay technologists geologists and soil scientists. H. van Olphen. Pp. 301. J. Wiley and Sons. New York. 1963. Chemistry and physics of rubber-like substances studies of the Natural Rubber Producers’ Research Association. Edited by L. Bateman. Maclaren & Sons Ltd. London. 1963. Corrosion. Edited by L. L. Shreir. 2 Vols. Newnes. London. 1963. Handbook of laboratory distillation. E. Krell. Edited by E. C. Lumb. (Translated from the 2nd German edition.) Pp. 561. Elsevier. Amsterdam. 1963. Informational macromolecules a symposium held at the Institute of Microbiology of Rutgers the State University 1962 with support from the National Science Foundation. Edited by H. J. Vogel V. Bryson and J. 0. Lampen. Pp. 542. Academic Press. New York. 1963. Gas chromatography :fourth International Symposium held under the auspices of the Analysis Instrumentation Division of the Instrument Society of America 1963. Edited by L. Fowler. Pp. 270. Academic Press. New York. 1963.
ISSN:0369-8718
DOI:10.1039/PS9640000073
出版商:RSC
年代:1964
数据来源: RSC
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