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Proceedings of the Chemical Society. December 1964 |
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Proceedings of the Chemical Society ,
Volume 1,
Issue December,
1964,
Page 385-434
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摘要:
PROCEEDINGS OF THE CHEMICAL SOCIETY DECEMBER 1964 SCIENTIFIC PROGRAMME MARKING THE OPENING OF THE NEW CHEMISTRY BUILDING AT THE TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY A DISTINGUISH~Dgroup of British and American chemists gathered in Haifa from October 1 Ith to 14th 1964 as guests of the Technion’s Depart- ment of Chemistry on the occasion of its removal to spacious new quarters on Mount Carmel. Professor D. Ginsburg Chairman of the department presided over the formal opening at which the guests were greeted on behalf of the home institution by its President General Y. Dori. The good wishes of Israel’s scientists were conveyed by Professor A. Katzir (Katchalsky) President of the Israel Academy of Science and Humanities and Professor S.Sarel President of the Israel Chemical Society both of whom con- gratulated Professor Ginsburg on the new build- ing the achievement of which is due in large measure to his vision and perseverance. The principal speaker of the afternoon was Lord Todd who developed the thesis that technology old as man himself became modern when it based itself on science whereas other branches of human endeavour still lag far behind because they do not. The speaker argued that it is the task of modern education to narrow this un- fortunate gap which is the source of many ills. The Israeli audience which was delighted by the faultless pronunciation of Lord Todd’s closing Hebrew sentences could only say “Amen” to his hope that the relatively tradition-free atmosphere of modern Israel will make the urgently needed adjustment of sociological attitudes to the present state of science less difficult than it might be elsewhere.The chairman then called on Lady Todd to cut the ribbon barring the main entrance and thus to end the ceremony by opening the new Chemistry Building for inspection. In the first session of the scientific programme Lord Todd gave a most interesting lecture on the synergistically active Ostreogrycin group of antibiotics in particular on the structure of Ostreogrycin A. Oxidative degradation and spectroscopic studies showed this to be a macro- cyclic peptide lactone incorporating an ap-un-saturated amide linkage a d2-pyrroline ring and a 1’3-diene system. Furthermore the course of hydrolysis of its tetrahydro-and perhydro-derivatives and their enolic reactions suggest that Ostreogrycin A also contains a latent acetonyl oxazole grouping and that the latter heterocyclic system is formed with great ease by the opening of a transannular hydroxymethylene linkage followed by recyclisation of the resulting aldehyde group.The second session was devoted to a most impressive lecture by Sir Christopher Ingold on electrophilic aliphatic substitution. The speaker began by noting how preconceptions based on what is known about nucleophilic aliphatic sub- stitution led to the search for mechanisms of types SEl,SE2 and SEi,but he was careful to point out the pitfalls of drawing too close an analogy between the two complementary classes of substitution reactions.Sir Christopher then described the concerted attack by a battery of kinetic isotopic and stereochemical techniques on Hg-Hg displacements which unequivocally demonstrated all of the three expected mechan- isms S,2 (with retention) as the general case; anion-catalysis of this mechanism which is essentially S,i in character; SEl heterolysis (with racemisation) which is obtained whether or not 385 carbanion formation is anion-catalysed with judiciously chosen alkylmercuric halides. The lecturer concluded with a brief description of work in progress on substitution by and of metal atoms other than mercury and held out the exciting prospect that rigorous mechanistic studies of electrophilic substitution are now capable of being extended via organometallics well into inorganic chemistry.Professor J. D. Roberts demonstrated in the third session how much valuable mechanistic information can be extracted from “a quarter of a millilitre of solution surrounded by $50,000 worth of equipment.” After reviewing the prin- ciples of nuclear magnetic resonance spectro- scopy as applied to kinetic studies Professor Roberts described how this powerful technique was brought to bear on the mechanism of electro- philic aliphatic substitution. The n.m.r. spectra of neohexylmagnesium bromide and of the cor- responding dialkylmagnesium show that the conformationally non-equivalent alpha-hydrogen atoms become equivalent as the temperature is raised.This presumably results from the in- creasingly rapid displacement with inversion of configuration of one MgX (or MgR) group by another. The kinetic effects of varying a number of factors :the concentration of the substrate the solvent the structure of the alkyl group the halogen and even that of changing the metal to lithium aluminium or mercury are all con- sistent with an SEl,or carbanion mechanism. Professor Roberts pointed out that this con-clusion is not at odds with that of Sir Christopher Ingold according to which the SE1mechanism is less facile than either SE2or SEi,since the latter two however rapidly they were taking place could only lead to retention of configura- tion and would not be detected.The last day was graced by the lectures of two guests from Harvard University who appeared to differ as much in the philosophy of their approach to chemical problems as they were alike in the ability to captivate their audience. Professor E. Bright Wilson regaled his audience with an exposition of his views on the role of theory in chemistry. Professor Wilson began by illustrating how much less amenable to rigorous theory is the subject matter of physical chemistry than that of physics and went on to outline the criteria by which the value of a theory should be judged. In the process the speaker PROCEEDINGS condemned the cardinal sins of extrapolation beyond the range of validity misuse of adjust- able and “hidden” parameters a posteriori rationalisation of exceptions and the like.According to Professor Wilson the primary requirement of a theory is its predictive power but its predictions must be verifiable otherwise unpredictable preferably quantitative and hope- fully believa ble-or no experimentalist will exert enough effort to confirm them. Addressing him- self specifically to mathematical theories the speaker illustrated his results abundantly with a mordant analysis of the various theoretical explanations of restricted rotation in ethane. At the conclusion of his vastly entertaining but most instructive lecture Professor Wilson extended cold comfort to the theoreticians in his audience by conceding that imperfect even false theories serve some purpose when they stimulate experi- mental research.In the closing session of the programme Professor R. B. Woodward treated us to an enthralling account of his present approach to the Herculean problem of the total synthesis of Vitamin BI2. He demonstrated how six of the nine asymmetric centres in the molecule can be assembled stereospecifically by a combination of two methods. In one induced asymmetric syn- thesis the introduction of a new asymmetric carbon is controlled by the configuration of an adjacent asymmetric centre or by the gross geometry of the molecular environment. The other that of absolute asymmetric synthesis ensures the correct absolute stereochemical sequence by the use of fragments derived from natural products of known absolute configura- tion.Among the highlights of his 25-hour lecture were (a)the use of a substituted iso-oxazole side- chain to fulfil the electronic requirements of a complex and stereospecific internal Michael addition; (b) the utilisation of newly discovered principles regarding the stereochemistry of heat- or light-induced alkatriene-cycloalkadieneinter-conversions; (c)a novel method of optical resolu- tion of a cyclic secondary amine; and (d)the use of compounds derived from either (+)-or (-)-camphor both to establish the absolute con- figuration of optically resolved intermediates and to provide additional links in the synthetic chain. E. A. HALEVI H. J. E. LOEWENTHAL. DECEMBER 1964 387 OTTO WALLACH A SHORT BIOGRAPHY By A.BLUMANN OTTOWALLACH was born at Konigsberg (East Prussia) educated at the “humanistic” gymnas- ium at Potsdam and already as a boy carried out chemical experiments at his parents’ Berlin home. Undeterred by the warning of a friend-“a chemist won’t even get a decoration”-he decided to study chemistry at Gsttingen Univer- sity founded by George I in 1737 a small rural place with only 800 students. However the famous Wohler taught there and the final examination could be passed in the shortest possible time. Wohler was already out of date. For him water was still HO and he was unable to under- stand the new developments in organic chem- istry so Wallach went to Berlin University. It was impossible to find a place in A. W.Hof- mann’s laboratory there he had to work in the private laboratory of Sonnenschein analy- tical chemist to the law courts and there was sometimes a stench of rotting parts of corpses at his rather miserable establishment. Wallach spent only one winter semestre there and returned to Gsttingen where he started work with Hubner since Wohler no longer took pupils. Within a short time he discovered a new crystalline bromotoluene by careful fractiona- tion but neither Hubner nor Fittig would believe in its existence. It did not fit into their theories. However Fittig recommended Wal- lach’s thesis to the faculty and he graduated as Dr. phil. in 1869. He went back to Berlin to become an assistant to Wichelhaus who kept a very primitive labora- tory in his house which adjoined the new build- ing of the Chemistry Department.Wichelhaus was one of the founders of the German Chemical Society (1 868) and the first editor of the Berichte. Wallach assisted him also in this function having joined the society in late 1869. Scientific life was very active with fortnightly meetings presided over by Hofmann and attended by such prominent men as Adolf Baeyer Victor Meyer Alphons Oppenheim Carl Liebermann and C. A. v. Martius. Within less than a year Wallach was offered a position as assistant to the famous KCkulC at Bonn University. The Franco-Prussian war broke out soon after. He volunteered but was not found fit enough and served for a while at the front with the Red Cross.Kkkulk soon wanted him back to assist him in lecturing but Wallach decided to accept an offer from his friend Martius to enter his new industrial enter- prise for manufacturing aniline which he had founded together with Paul Mendelssohn-Bartholdy (the son of the composer) and which later developed into the well known “Agfa”. However he had to resign after half a year suffering one attack of catarrh after the other from inhaling the poisonous fumes. Sanitary conditions for workers and chemists were un- known in those days. After a short time of work with Wichelhaus he went back to Bonn on a salary of 975 marks (E48 15s.) a year but with the prospect of becoming a lecturer soon. He was going to stay there for 17 years and publish more than 70 papers on various subjects before he started on his life work on terpenes and essential oils.Wallach enjoyed living in the easy-going Rhineland and was stimulated by the scientific activities at Bonn. He was appointed successor of Theodor Zincke and in the following year became Associate Professor earning a salary of 6,000 marks at an age of 29 years. While in charge of the inorganic chemistry section he had also to look after students in organic chemistry apart from supervising the work of collaborators. His lectures were already becoming popular and he did a lot to improve the teaching of analytical chemistry. When Friedrich Mohr Professor of Pharmacy in a separate institute died he fol- lowed him as Head of the remodelled School of Pharmacy at Bonn University.This appoint- ment became decisive for the rest of his life. During a visit to Kkkulk’s rooms he saw a collec- tion of bottles with essential oils a present from a manufacturer to the famous scientist and he asked KCkuIC whether he would allow him to experiment with them. The chief answered smiling ironically “By all means yes if you can get something out of that stuff. ..” Something similar happened once to young A. W. Hofmann who wanted to examine the constituents of coal tar and was told by Liebig “Leave that alone you cannot do anything with such rubbish”. Doubts of famous people sometimes inspire the opposition of their young subordinates. After the publication of his first paper “On oleum cinae,” Wallach published on the subject of terpenes and essential oils at increasing speed.His reputation grew in consequence and he was called on to succeed the great Victor Meyer as Professor of Chemistry at Gottingen 20 years after he had entered the Georgia Augusta as a student. From now on his scientific career was an unbroken success. In 1909 a celebration took place to commemorate the publication of the 100th “terpene paper,” with great participation from university staffs industry and present as well as former pupils. But he saw his main task in the organisation of teaching and the running of the Chemistry Department. This proved to be difficult at the start. An old protkgi of Wohler also with side whiskers who was employed in setting up apparatus for experiments during lectures once remarked to Wallach on the occa- sion of some mishap “This would not have happened under the late privy senior medicinal counsellor” (Wohler’s title) whereupon he was immediately relieved from his job.Wallach knew how to make the rather stubborn labora- tory personnel respect him soon. He vigorously organised the teaching after every young lecturer and assistant had gone to Heidelberg with V. Meyer and a lot of new ones had to be ap- pointed. Their numbers were constantly re-stricted by the stingy Prussian Ministry of Public Worship and Education. Wallach took his duties as a teacher very seriously. He lectured in inorganic experimental chemistry every morning in winter and in organic five times a week during summer.His lectures were always stimulating informative and illustrated by well prepared experiments. He spoke a perfect German with a clear voice understandable at the furthest end of the lecture theatre and it was a pleasure to look at the experimenter with his fresh face and white beard in his elegant black frock coat. A serious accident happened to him on December loth 1895. As was later discovered his assistant had received a gasometer from a laboratory em-ployee which had previously contained acetylene. Oxygen had been put in instead and Wallach was assured by both men that the oxygen was pure. Unfortunately it was not and the other- wise harmless experiment of burning selenium in the oxygen resulted in a terrible explosion.PROCEEDINGS Wallach collapsed covered in blood. Most of the students ran away some lightly injured. The only female student and a student of medicine remained and they together pressed the cut temporalis and bandaged it till the Professor of Surgery arrived after 45 minutes. An injury of the left wrist overlooked at first was more serious and Wallach was unable to use his left hand properly ever after. He also suffered from an eczema from time to time through contact with ethyl bromoacetate and some essential oils. The student’s laboratory work was considered of great importance and Wallach visited the various laboratories regularly talking to every student about his work. He discussed work with his own “doctorands” who worked on their thesis twice a day and when a result of im- portance had been achieved asked a student to follow him into his private laboratory commonly known as the “crystal palace” where everything sparkled and gleamed and where he checked m.p.aD nD and density personally. Nobody could fool him. Wallach’s pioneering work on terpenes was soon followed up by other scientists. Julius Bredt published his correct configuration of camphor as early as 1893 and there was soon lively com- petition among a number of people working in what Wallach considered “his field”. He did not mind Tiemann Wagner Aschan Komppa and W. H. Perkin. With the latter he was even on very friendly terms. But he could not stand Semmler and despised Kondakow.As regards the great Adolf Baeyer he disapproved of his work on terpenes and once when he had sug- gested an improvement on Baeyer’s oxidation of nopinic acid he remarked to me triumphantly after success “Well isn’t it so much better than Baeyer’s mess?” In 1909 Leipzig University had made him a Dr. med. h.c. and on the occasion of the opening of Sir Henry Roscoe’s new laboratory the degree of D.Sc. was conferred on him. He stayed at W. H. Perkin’s house as a guest and there made the acquaintance of W. N. Haworth who went to Gottingen later to work with Wallach and graduated as Dr. phil. Wallach visited England again in November 1910 to attend a meeting to honour Past Presidents of the Chemical Society in London of which he was an honorary member.He had already been elected President of the DECEMBER 1964 German Chemical Society. On his return journey he learnt from a Hanover paper that he had received the Nobel prize. Many more honours were going to follow. He received the Davy medal of the Royal Society on the occasion of their 250th anniversary the Technical Univer- sity of Brauschweig made him a Dr. Ing. e.h. and the University of Frankfurt a Dr. Phil. h.c. Wailach had already applied to the Ministry to be relieved from his post when the 1914-18 war broke out. He was succeeded on October lst 1915 by Adolf Windaus but continued to work in his private laboratory and even assisted in the Department of Organic Chemistry during the serious shortage of staff.Until the age of 80 he published a few more papers and maintained hi3 visits to the laboratory and his keen interest in scientific meetings until 1930. Then he had a stroke and died half a year later. His pioneering work lives on and is still of influence in organic chemical research particu- larly in the field of natural products such as steroids and triterpenes. By the reward of the Nobel prize he was acclaimed as a great scientist. But he was not a genius like Victor Meyer or Emil Fischer; his greatness lay in the combination of his research and teaching work. His clear thinking and vast knowledge were remarkable his experimental skill outstanding and his gift of observation exceptional. We all benefited from and soon shared his enthusiasm.He was well known for his astounding sense of smell. “So you found a new ketone. Did you purify it through the semicarbazone ?” “Not yet.” Wallach put a small drop on his left hand rubbed it with the right and smelt fractionating it by odour “Some saturated plus some un-saturated hydrocarbon saturated alcohol un-saturated alcohol-and a little bit of ketone.” Most of his holidays were spent in Italy a country he loved and from which he brought a collection of fine paintings to his well furnished house next to the General Chemistry Depart- ment. He kept an excellent table knew how to choose his wine and was a charming host friendly kind and wise. His scientific work has been comprehensively reviewed in W.Huckel’s excellent biography “Otto Wallach In Memoriam,” published by Verlag Chemie in 1960. CHEMICAL SOCIETY SYMPOSIUM The chemical significance of the Mossbauer effect ONEcould readily forgive the average chemist for being unexcited with the result that the east-west component of the aether drift at Birmingham is less than 3 metres per second,’ but it would be hard to approve of any lack of interest in how such a state- ment was experimentally made possible. Curiosity may have led our chemist. however “sceptical.” to published reviews of the Mossbauer and to Queen Mary College in the new London Borough of Tower Hamlets where the chemical significance of this effect was discussed on October 29th in a Symposium organised by the Chemical Society.The proceedings began promptly at 2 pm. in the new College Lecture Theatre under the chairmanship of Professor K. W. Sykes a prime mover of the Symposium in the regretted absence due to illness of Sir Christopher Ingold. The first of five talks was presented by Dr. L. G. Lang who is at Nuclear Physics Division A.E.R.E. Harwell while on leave from the Carnegie Institute of Technology Pittsburgh. Dr. Lang introduced the audience of approximately two hundred people to the “Nuclear Physics of the Mossbauer Effect.” The experiments consist of the measurement of trans- mission by a resonant solid absorber as a function of incident very monochromatic gamma energy produced by a suitable solid source. The frequency of the radiation as presented to the absorber is varied by means of the Doppler effect.The accoutrements or “hardware” involved were briefly described ar?d the audience thereby introduced to the new perhaps unfamiliar jargon (e.g. kicksorter instantaneous address recoiless events) which proved useful to later speakers. The chemist’s turn came with Dr. D. H. Whiffen of The National Physical Laboratory Teddington who claimed to be unsullied by experimental ex- perience of the technique. The Grecian aloofness was justified by the clarity of the exposition of the factors governing the spectral parameters of “isomer shift” D. C. Champeney G. R. Isaac and A. M. Khan Phys. Letters 1963 7 241. “Some Applications of the Mossbauer Effect,” P. B.Moon and D. A. Connor Endeavour 1964 23 131. “The Mossbauer Effect and its Significance in Chemistry,” E. Fluck W. Kerler and W. Neuwirte Angew. Chem. Znternat. Edn. 1963 2 277. (the frequency difference of the centre of absorption between a sample and a reference) and quadrupole splitting of Mossbauer lines. Shifts give information about s electrons whereas quadrupole splittings can be related to the electric field gradient at the nucleus which is dominated by the p electrons of the valence shell. The points were illustrated by reference to the Mossbauer spectra of the ferrocyanide ferricyanide iron carbonylnitrosyl complexes and of potassium iodide potassium iodate ammonium iodate and potassium periodate. A short discussion brought the first session to an end.After tea the second session which consisted of more specialised papers than those given previously began with two talks from Professor N. N. Green-wood’s group at the University of Newcastle-upon- Tyne. In the first Mr. T. C. Gibb gave an excellent account of the “Mossbauer Effect in Iron Borides and Silicate Minerals.” Analysis of the fine structure in the spectra of Fe,B and FeB has confirmed that electron transfer occurs from boron to metal. The talk concluded with an account of the oxidation states of iron present in natural South African Crocidoli te. Professor Greenwood himself presented the second contribution from his group “Mossbauer Effect in Compounds of Tin and other Elements.” It took the form of a succinct appraisal of the characteristics required of a Mossbauer nucleide to enable it to be used conveniently in chemical experiments followed by a review of work involving a nucleide which is among the easiest to study viz.tin. The absence of PROCEEDINGS quadrupole splitting in several cases for which it was anticipated was mentioned and this point was returned to in the subsequent discussion. The question of quadrupole splitting was raised again after the last talk by Dr. M. J. Rossiter (D.S.I.R. Isotope Application Unit Wantage Re- search Laboratory) which concerned “Ferric Oxy- hydroxide and some Spinel Solid Solutions contain- ing Iron.” Dr. Rossiter showed how Mossbauer studies helped in the deduction of cation valency and site distribution in Spinel oxides.Effects of paramag-netism and antiferromagnetism were outlined and the Mossbauer spectra of the four crystal forms of ferric oxyhydroxide were compared with magnetic measurements on the same species. The Symposium was concluded at approximately 6.30 p.m. after an announcement requesting that chemists interested in participating in a Mossbauer discussion group should write to Professor Green- wood. Speakers differed in the use of the umlaut; there was no apparent geographical correlation. Variations occurred also in the line-shapes used by authors for curve-fitting;Dr. Rossiter’s rather gothic presenta- tions were the most pleasing. The participants were all graciously invited to a Sherry Party by the Principal of Queen Mary College after which a select group attended the Symposium Dinner.The selection rules on this occasion were not discussed. E. W. Randall. Letter to the Editor Sir The development announced in the current number* of the Proceedings is seriously at variance with the “main object” of the Society defined in the leaflet circulated with it as “to advance the science of chemistry by means of discussion and publication of new discoveries.” In accordance with this Fellows used to receive Proceedings Journal and Abstracts. Of these the last have been supplanted and economic conditions have put the Journal beyond the reach of most Fellows. In these circumstances the Proceedings in modern- ised form with Memorial Lectures and original Communicationsof permanent value have remained symbolic of the Society’s function and a welcome palliative of our losses.Now we learn that it is actually planned to impose at short notice a sur- charge in order to give preference to a magazine reflecting in its title an insular concern rather than * 1.e. September issue.-ED. the international character of science and to contain a quantity of merely ephemeral matter such as is already available in a number of periodicals. The Fellows have given no mandate for such a subversion of the Society’s declared priorities and the offence is aggravated by a gratuitous reproof to those upwards of three-quarters of the Fellows who have not chosen to join the Royal Institute of Chemistry.It should have been evident that the price of any rapproche- ment with the Institute must not include grave dis- service to the Fellows and it must accordingly be hoped that the contemplated arrangement will be suitably modified. Yours faithfully J. KENNER. 41 Burlington Road Withington Manchester 20. October 21st 1964. DECEMBER 1964 391 COMMUNlCATIONS Stable Carbonium Ion Salts as Initiators for Vinyl Polymerisations By C. E. H. BAWN,C. FITZSIMMONS, and A. LEDWITH* STABLE carbonium ion salts are extremely useful ini- was obtained from a detailed investigation of the tiators for cationic polymerisations. In particular tri- polymerisation of isobutyl vinyl ether as shown in phenyhe t h yl hexachloroant hona t e (Ph,C+S bCI,-) the Table.has been used to investigate the polymerisation of The two catalysts Ph,eSbCl,- and C,H,+SbCl,- tetrahydrofurad and alkyl vinyl ethers where the both gave rapid and complete initiation and the initiation reaction involves addition of Ph,C+ to the absence of termination was evident from the repro- monomer or formation of Ph,CH by hydride-ion ducibility of initial reaction rates upon addition of abstraction. With the much more stable tropylium fresh monomer to unquenched but completed poly- (C,H,+) cation and common vinyl monomers these merisations. With Ph,C+SbCl,-as initiator it is initiation mechanisms can be virtually eliminated certain that a classical carbonium-ion polymerisation from consideration of relative carbonium ion is involved and the very close agreement between stabilities.rate and molecular-weight data obtained with this Using methylene chloride and acetonitrile as and C,H7+SbC16- as initiator confirms the cationic solvents it has been found that tropylium hexa- nature of the polymerisations initiated by the chloroantimonate (C,H,+SbCl,-) and tropyhm tropylium salt. tetrafluoroborate (C,H,+BF4-) can be used to The tropylium-ion initiation reaction is thought to initiate the polymerisation of alkyl vinyl ethers occur via formation of radical-cations i.e., N-vinylcarbazole acenaphthylene 1-and 2-vinyl- naphthalene vinylmesitylene and styrene. Tropylium C7H7+SbC1,-I-CH,=CH-OR + [Complex] -+ salts are known to form stable charge-transfer com- + C7H7. + .CH,-CH= ORSbCI,-.plexes with aromatic donor molecules3 and signi- ficantly initiation of polymerisation occurs after Polymerisation can occur at both radical and initial formation of coloured charge-transfer com- cationic ends of the cation radical but the radical end plexes between monomer and the C7H$ ion. The will quickly terminate leaving a conventional car- monomers listed are known to be susceptible to bonium ion-pair as the active intermediate. This type cationic p~lymerisation~ and it seems likely that the of initiation is analogous to that characterised by C,H,+ initiated polymerisations also follow a car- Szwarc' for anionic polymerisations with the bonium-ion mechanism. Support for this assumption sodium-naphthalene ion-pair as initiator and may Polymerisation of isobutyl vinyl ether in CH,CI at 0" [CH,= CHOBU'] Initiator Overall rate Polymer (M) coefficient* viscosityt [Ph,C+SbCl,] [C,H,+SbCI6-] lo- k 1771 (1 05M) (1.mole-l sec.-l) (dl. g.-l) 0.079 5-64 3.0 0.071 0.19 1.93 3.6 0.087 0.19 3-75 3.7 0.083 0.19 5.57 3.6 0.084 0.19 7-42 3.4 0.084 0.19 7.1 4.1 0.085 0.08 5.32 5.0 0.072 * Reaction rates were followed in vucuo in an adiabatic calorimeter essentially as described by Biddulph and Plesch.6 The rate coefficient was estimated from the expression -d[Monomer]/dr = kp [Monomer][Catalyst]. Measured in benzene at 25"c;the yield of polymer was always quantitative. * Department of Inorganic Physical and Industrial Chemistry University of Liverpool. C. E. H. Bawn R.M. Bell and A. Ledwith Anniversary Meeting of the Chemical Society Cardiff 1963; C. E. H. Rawn R. M. Bell and A. Ledwith Polymer in the press. C. E. H. Bawn A. Ledwith and J. Penfold unpublished work. M. Feldman and S. Winstem J. Amer. Chem. Soc. 1961 83 3338. * The Chemistry of Cationic Polymerisation Ed. P. H. Plesch Pergainon Press Oxford 1963. R. Biddulph and P. H. Plesch Chem. and Ind. 1959 1482. M. Szwarc Adv. Polymer Sci. 1960 2 275. PROCEEDINGS ~~ be involved in other charge-transfer complex-It is worth noting that the value of the propagation initiated polymerisa t ions reported recently. rate constant obtained in the present work (k -3.5 The charge-transfer complex between isobutyl x 1031. mole-l sec.-l at 0"c) is several orders of vinyl ether and C7H,+SbCl,- was only transient at magnitude greater than that reported8 for the iodine- room temperature but had a significant lifetime catalysed polymerisation of the same monomer in 1,2-dichloroethane (kp -6-5 1.niole-l sec.-l at below -30"c and it is hoped to characterise this and related complexes by low-tempera ture absorption 30"c). spectrophotometry. (Received November 2nd 1964.) Ellinger Chem. and Ind. 1963 1982; Polymer 1964,5 559; H. Scott G. A. Miller and M. M. Labes Tetrahedron Letters 1963 1073. * S. Okamura N. Kanoh and T. Higashimura Makromol. Chem. 1961 67 35. The Dissociation of Ethane By R. W. DEXTER and A. B. TRENWITH* SOME doubt exists as to the order of the reaction Since at low pressures methane formation is C2H -2CH,* under conditions employed in the directly proportional to heating time for periods of pyrolysis of ethane.Dodd and Steaciel studied the up to 15 min.? it was assumed that under the experi- reverse reaction at 147-247" and found it to be just mental conditions employed the first order rate in its third-order region at 200"and 1 mm. pressure. constant for the dissociation reaction is given by Thus by the principle of microscopic reversibility k = [CH4]/(2[C,H,] x heating time). The results the dissociation of ethane should be of second order plotted as log,, k/k against logloethane pressure below 1 mm. prsssure at 200". Using this result (mm.) are shown in the Figure. For comparison Laidler and Wojciechowski,2 by application of the curves of log, k/k against loglopressure which Hinshelwood-Rice-Ramsperger theory of unimole- have been calculated from the classical form of cular reactions predicted that at 600" the reaction Kassel's theory with s = 15 and s = 16 are included will certainly be of second order at pressures up to in the Figure.For each Eact was taken as 88 kcal./ who measured the rate mole4 and from the experimental value of kco,A, 180 mm. In contrast Q~inn,~ sec.-l. A value of 4-30A was of dissociation of ethane by determining the rate of was found to be 1016*37 formation of methane produced by the subsequent taken for the collision diameter of ethane. step CH,. + C2H -CH 4-C,H,* found the dissociation reaction to be still in its first-order region log P (mm.) at pressures as low as 60 mm.The preliminary experiments described here were carried out with a view to finding the pressure at which the first-order rate constant for the dissocia- tion of ethane begins to fall off from its high- pressure value. Ethane was pyrolysed at 567" and after heating times of 5-10 min. the products were collected in a series of four traps at -196" the first three being empty and the last containing molecular sieve 5A. The contents of this last trap (methane and hydrogen) were analysed for methane in a Perkin- Elmer Fractometer a 1-m. molecular sieve 5A The experimental first-order rate constant falls column being used at 50" with hydrogen as carrier measurably from the high-pressure value at pres- gas. For the pyrolysis at the lowest pressures the sures below 100 mm.and the order of the dissocia- products of two or three identical runs were com- tion reaction rises to approximately 1.2 at 10 mm. bined to give sufficient methane for accurate pressure. measurements. (Received October Sth 1964.) * Department of Inorganic Chemistry University of Newcastle upon Tyne. 1 R. E. Dodd and E. W. R. Steacie Proc. Roy. SOC.,1954 A 223 283. K. J. Laidler and B. W. Wojciechowski Proc. Roy. SOC.,1961 A 260 91. C. P. Quinn Proc. Roy. Soc. 1963 A 275 190. S. W. Benson "The Foundations of Chemical Kinetics," McGraw-Hill Book Co. Inc. New York 1960 p. 354. DECEMBER 1964 393 New Fluorides of Palladium :Palladium(n) HexafluoropaIladate@) and Related Compounds and Palladium Tetrafluoride By NEIL and P.R. RAO* BARTLETT Two binary fluorides of palladium a difluoride,l and a trifluoride2 have been described. The difluoride is the only simple Pd(n) compound which is paramag- netic the high spin valency electron configuration being compatible in terms of ligand field theory with the observed octahedral co-ordination of the palladium by fl~orine.~ However in the case of the supposed trifluoride magnetic measurements4 had been interpreted as indicating a low spin electron configuration d&,eg for the octahedrally co-ordinated5 Pd2+ ion. Ligand-field theory however predicts a distorted environment for an ion with such a configuration. We have resolved this difficulty by demonstrating that the "trifluoride" is the mixed valency compound palladium(n) hexafluoropal-ladate(Iv) Pd2+[PdF6]2-.The Pd2+ ion is assigned the high spin electron configuration associated with the difluoride and the Pd4+ ion is given the low spin configuration d&, associated with the PdF6% ion as in the hexafluoropalladates(rv) which are diamagnetic. Measurements over the temperature range 97- 298"~have established the magnetic susceptibility of PdPdF to obey the Curie-Weiss law with 8 = 28". The effective temperature-independent magnetic moment based on the formula unit Pd2F6 is 2-88 B.M. which is similar to the spin only moment based on Pd2+[PdF,I2-. Palladium(I1) hexafluoropalladate(1v) may be obtained2 by the sequence of reactions 2PdBr2 + 180" 4BrF -2 [PdF,,BrF,] ;2 [PdF,,BrF,] -4PdPdF, + 2BrF, which indicates the coexistence of Pd(r1) and Pd(1v) in neutral bromine trifluoride.Further- more earlier work6 had shown that in the presence of good fluoride-ion donors (i.e. basic conditions) bromine trifluoride gives rise to Pd(Iv) e.g. 6[PdF3,BrF,] + 12SeF4-6(SeF3),PdF + 4BrF, + Br,. It therefore appeared probable that good fluoride-ion acceptors would stabilise Pd(I1) in bromine trifluoride and this has proved to be so. In particular a series of compounds of general formula Pd2+[MF,I2- has been prepared by the addition of bromine trifluoride to stoicheiometric mixtures of palladium(@ bromide and the appropriate acid former 3PdBr2 + 3Ge02 + GBrF -3PdGeF6 + 302 + 6Br2; PdBr + Pt(or Sn)Br4 + 2BrF -PdPt(or Sn)F -I-4Br2 (Found F 38-2; Ge,25.4; Pd 36.4.PdGeF requires F 38.9; Ge 24.8; Pd 36.3%. Found F 27.0; Pd 25.1; Pt 47.8. PdPtF requires F 27.4; Pd 25-6; Pt 47.0%. Found F 32-6; Pd 31.9; Sn 35.5. PdSnF requires F 33.6; Pd 31.4; Sn 35.0%). The hexafluorostannate by virtue of its greater anion size has the largest unit cell a = 5.70 f0-02A a = 53.13 f0.05" the unit cells of the other salts being closer to that of PdPdF, a = 5.523 f0.001 A 01 = 53-93f0.01"; PdGeF, a = 5-53 f0.01 A 01 = 54.0 &-0.02"; PdPtF, a = 5-55 f0.01 A 01 = 54.0 & 0.02". All of the salts are similar magnetically to Pd2+[PdF6I2- with the values of peff(temp. indep.) and 8 being respectively PdSnF, 2.98 B.M. 28"; PdGeF, 2-82 B.M. 31" and PdPtF, 2.72 B.M.1.2". The thermal decom- position of PdGeF in vacuu at 350" is a new and convenient route to the difluoride PdGeF -PdF -t GeF,. Fluorination of Pd2+[h.IF,]" salts with gaseous fluorine in the temperature range 150-300" yields the tetrafluoride of palladium in the case of PdPdF and the mixed tetrafluorides in the other cases. The tin compound is the most easily oxidised and is com- pletely fluorinated at 150". The diamagnetic brick- red solid gives a tin tetrafluoride powder diffraction pattern the crystals of palladium tetrafluoride formed at this temperature being too small to give a powder pattern (Found F 40.4; Pd 28.5; Sn 32.4. Calc. for PdF, SnF, F 40-3; Pd 28-2; Sn 31.5 %). Relatively sharp X-ray powder patterns of palladium tetrafluoride have been obtained from the brick-red solid produced by fluorinating Pd2+[PdF6I2- at 300" under a 100 lb./sq in.pressure of fluorine but samples of crystalline material have always shown the faint pattern of Pd2+[PdF6I2-. The tetra- fluoride has a tetragonal unit cell a = 6.585 f 0.0005 A C = 5-835 f0-005 A; V = 253 Z = 4; S. G. D:E-l4/amd. It is structurally similar to PtF,.' Samples prepared at 300" are weakly paramagnetic the paramagnetism being attributable to Pd2+[PdF,I2-. For the best crystalline sample Xg2980 = 1.23 x lo- c.g.s. units whereas * The Chemistry Department The University of British Columbia Vancouver 8 B.C. Canada. N. Bartlett and M. A. Hepworth Chem. and Ind. 1956 1425. A. G. Sharpe,J. 1950 3444.N. Bartlett and R. Maitland Acta Cryst. 1958 11 747. * R. S. Nyholm and A. G. Sharpe,J. 1952 3579. M. A. Hepworth K. H. Jack R. D. Peacock and G. J. Westland Acta Cryst. 1957 10 63. N. Bartlett and J. W. Quail J. 1961 3728. N. Bartlett and D. H. Lohmann J. 1964 619. XgZg80 Pd"[PdF6l2-= 9.771 x c.g.s. (Found F 40.7; Pd 58.5. PdF4 requires F 41.7; Pd 58.3. Calc. for PdF, F 34-9;Pd 65.1 04). The tetrafluoride is easily reduced to Pd2+[PdF6l2- and reacts violently with water with the liberation of PROCEEDINGS ozone-smelling gases. It shows only slight increase in Pd2+[PdFJ2- content after three hours under vacuum at 200". Decomposition is rapid above 3500. (Received October 23rd 1964.) Amide as a Protecting Group in Phosphate Ester Synthesis By W.J. HOPWOOD, P. D. REGAN,and J. A. STOCK* WE report a preparative non-hydrolytic method of converting N-a1 kylp hosphoramidic diesters (I) in to the corresponding phosphate diesters (11) in high yield. A solution of the amidate (I; R = Ph R' = Me) in chloroform at 0" containing an equivalent of pentyl nitrite was treated with one equivalent of a strong acid (hydrogen chloride sulphuric acid or (RO),P(:O)N H R' (RO),P(:O)OH (RO),P(:O)OR' (1) ('1) (111) CI P(:0)N H R' ( Ph0) P( 0)N(N0)Ar ( Ph0)P( 0)0N NA r (IV) (V) (VI) toluene-p-sulphonic acid) in an organic solvent and the mixture set aside at room temperature; gas evolu- tion was observed. Sodium hydrogen carbonate ex- traction gave diphenyl hydrogen phosphate (TI; R = Ph) identified by m.p.(66-68"; 1it.l 67-69') mixed m.p. infrared spectrum and by comparison of the crystalline cyclohexylammonium and dicyclo- hexylammonium? salts with authentic samples. The N-methyl compound (I; R = Ph R' = Me) gave the best yield (75-800//,) of diester (11); other analogues (I; R' -Et the four Bu isomers cyclo- hexyl) were less satisfactory. The chloroform layer after extraction contained unchanged phosphor- amidate and the corresponding alkyl diphenyl phos- phate (111; R = Ph) identified by comparison with authentic material (i.r. spectra and thin-layer chromatography). A better conversion of the N-methyl compound was achieved with 1.5 equivalents of pentyl nitrite and acid; the yield of acid (11; R = Ph) was nearly 90%.The only other product isolated was the tri- ester; no starting material was recovered. When pentyl nitrite was omitted from the reaction starting material was recovered quantitatively. Di-n-butyl N-methylphosphoramidate (I; R =1 n-Bu R' = Me) under the same conditions (1.5 equivalents of pentyl nitrite) produced a 90-95% yield of the acid (11; R = n-Bu) identified by refractive index and m.p. of its anilinium salt (1221.4270 67-68'; lit.2 nE 1.4275 67-5-68-5'). The diethyl analogue (I; R = Et R' = Me) behaved similarly. The small neutral fraction from each of these experiments was homo- geneous (thin-layer chromatography); it was not starting material and was probably the correspond- ing ester (111).Pentyl nitrite does not appear to have been used before in this context. The reaction outlined thus provides an easy method of converting the readily available N-alkyl- phosphoramidic dichlorides (IV) into phosphate diesters via the corresponding amidates (I). Hamer has reported3 that nitrosation of N-alkyl- phosphoramidic diesters gave oils which evolved nitrogen but he did not characterise the "complex" products. On the other hand Bunyan and Cadogan showed4 earlier that diphenyl N-arylphosphoramid- ates (I; R = Ph; R' = aryl) gave on nitrosation diphenyl hydrogen phosphate in low yield. A rapid rearrangement of the supposed intermediate N-nitroso-amide (V) to the diazo-ester (VI) was the suggested reaction path.4 N-Nitroso-carboxamides are also thought to rearrange to the corresponding diazo-esters and two mechanisms have been sug- gested for their subsequent decomposition.One involves formation of a dia~oalkane,~ and the other oriented ion-pairs.6 Participation of diazoalkanes in the phosphoramidate conversion is unlikely as we have found that diphenyl hydrogen phosphate is readily esterified by diazomethane. The operation of either mechanism would in any case presumably lead to triester (111). (Received July 24th 1964.) * Chester Beatty Research Institute Institute of Cancer Research Royal Cancer Hospital London S.W.3. f Satisfactory analytical values were obtained for this new compound. E. Cherbuliez and J. P. Leber Helv. Chim. Acta 1952,35 644.A. Zwierzak Bull. Acad. Polon. Sci. Ser. Sci. Chim. 1963 11 333. N. K. Hamer J. 1964 1961. P. J. Bunvan and J. I. G. Cadoaan. J.. 1962. 1304. A. Streitweiser and W. D. Schaeffer J. Amer. Chem. Soc. 1957 79 2893; E. H. White and C. A. Aufdermarsh, ibid. 1961 83 1174. R. Huisgen and C. Riichardt Aimden 1956 601 1; E. H. White and C. A. Aufdermarsh,J. Amer. Chem. Soc., 1961 83 1179. DECEMBER 1964 395 The Structure of ~-o-Phenylenebisdimethylarsine-te~~rb~nyl~-methylcyclopen~d~enyl~~g~~I) By M. J. BENNETT and R.MASON* THEchelating properties of o-phenylenebisdimethyl- arsine (diars) are well known although complexes containing a bridging diarsine group have been pre- pared only recent1y.l A structural analysis of [n-CH,C5H4.Mn(C0),],diars based on three-di-mensional X-ray methods (Rhkl = 0.086) allows us to comment on the nature of the bridging group and on its stereochemistry vis h vis that in such chelated diarsine complexes as M(diars),I (M = Pt,2 Pd.3 and Ni4).the manganese and arsenic atoms. The Mn-C(0) bond lengths suggest that n-bonding has reduced the Mn-C single bond by 0.31 A in the diarsine complex compared with 0-28 A in n-C,H,Mn(CO)3. The difference of 0-03 A is scarcely significant but the implication that the diarsine ligand is a less strongly n-accepting ligand than the replaced carbonyl group is borne out by the available infrared spectral data. The stretching frequencies of the carbonyl groups in n-C,H,Mn(CO) (2023 and 1939 cm.-l)' are reduced TABLE 1.Molecular dimensions in r-C,H,Mn(CO) and [n-CH,C,H,-Mn(CO),],diars. Molecule Bond lengths (A) Bond angles Mn-C(n-C,H,) Mn-C(0) O(C)-Mn-C(0) O(C)-Mn-As n-C,H,Mn( CO) 2-15 1 -80 91 ",91 O 94" -[n-CH,~C,H,-Mn(CO),],diars 2.15 1 -77 94" 91" 91" TABU2. Bond angles around the arsenic atoms in Ni(diars),I and [n-CH3C,H4-Mn(CO),1,diars. Bond angles Molecule A B M-As-CH M-As-C(pheny1ene) H~C-AS-CH The molecule has exact two-fold symmetry the molecular and crystallographic diad axes in the space group C2/c being coincident. The overall stereochemistry is shown in the Figure the As-CH and As-Mn bond directions being rotated through 85O about the arsenic-phenylene carbon bonds with respect to their conformation in the chelated com- plexes.Average e.s.d.'s of the observed bond lengths are 0.005 (Mn-As) 0.03 (Mn-C) 0.03 (As-C) and 0.048 (C-C). As Table 1 summarises there are some striking similarities between the present structure and that of n-cyclopentadienyltricarbonylmanganese(I),5 the steric requirements of the arsine ligand being apparently equivalent to that of the replaced carbonyl. A recent analysis6 of bond lengths in organo- metallic molecules has suggested that the covalent radius of "octahedral" (n-C,H being imagined as a formally tridentate ligand) Mn(r) is 1-38 f0.03 A so that the sum of covalent radii for Mn(r)-As is 2.56 A the arsenic radius being estimated from three independent C-As bond lengths. This value is 0-19A longer than the observed bond length of 2-37A and the difference must be due to dr-dn bonding between 119"(avg.) 1 16"(avg.) 109"(avg.) 120" 102"(avg.) 97" by ca.80 cm.-l in [n-CH,.C,H,-Mn(CO),],diars and [n-C,H,Mn(C0)2],diars (1934 and 1862 cm.-l).l I I I c Comparison of the metal-arsenic bond lengths in [n-CH,C,H,.Mn(CO),],diars and Ni(diarsJ1 sug- gests that there is more double bond character in the Ni-As than in the equivalent Mn-As bond since the observed Ni-As bond length is quoted4 as being 0.28 8 shorter than the sum of the covalent radii of nickel and arsenic. This result however rests on the * Department of Chemistry The University Sheffield. t R. S. Nyholm S. S. Sandhu and M. H. B. Stiddard,J. 1963 5916. -N. C. Stephenson J. Inorg. Nuclear Chem.1963,24 791. N. C. Stephenson J. Inorg. Nuclear Chem. 1963,24 797. N. C. Stephenson Acta Cryst. 1964 17 592. A. F. Berndt and R. E. Marsh Acta Cryst. 1963 16 119. M. J. Bennett and R. Mason in press. ' F. A. Cotton A. D. Liehr and G. Wilkinson J. Inorg. Nuclear Chem. 1955 1 175. assignment of an average covalent radius for Ni(n) in a system where the metal co-ordination is a tetra- gonall y distorted octahedron. The arsenic bond angles (e.s.d. 2”) show con- siderable distortions from tetrahedral values ;Table 2 summarises the relevant data for Ni(diars),I (A) and [n-CH,.C,H,-Mn(CO) ,],diars (B). These distortions were originally explained4 in terms of steric interactions between the iodine atoms and methyl groups.In the absence of such effects in PROCEEDINGS the bridging diarsine complex we prefer to believe that they indicate a change of hybridisation of the arsenic atoms resulting from either the metal-arsenic .rr-bonding or from repulsion between the lone pairs on the metal ion and bonding electron pairs on the arsenic atoms. We are grateful to Professor R. S. Nyholm and Dr. M. Stiddard for providing us with a sample of the com-plex. (Received November 9th 1964.) Formation of Free Radicals in Friedel-Crafts Reactions R. N. HASZELDINE, By R. E. BANKS,L. F. FARNELL P. N. PRESTON and L. H. SUTCLIFFE* RECENTLY, Adams and Nicksicl used electron-spin resonance techniques to demonstrate that free radicals are generated in Friedel-Crafts alkylation systems containing benzene aluminium chloride and an alkyl halide or an olefin; quantitative measure- ments were made on systems comprised of benzene aluminium chloride and (i) benzyl chloride (ii) di- chloromethane (iii) 1 ,Zdichloroet hane or (iv) 1-chlorobutane.The radicals which had g-values expected for hydrocarbon species were not identi- fied and it was suggested that they were either (a) intermediates associated with the mechanism of Friedel-Crafts alkylation reactions or (b) derived from the reaction products. As part of a study of Friedel-Crafts complexes,2 systems (i) and (ii) have been examined and the paramagnetic species generated in each case has been recognised as the anthracene positive radical-ion. This result is readily understood under the influence of aluminium chloride anthracene is formed by self- condensation of benzyl chloride and also by reaction of dichloromethane with ben~ene;~ and anthracene is known to partake in an electron-transfer reaction with aluminium chloride to yield anthracene positive radical-ions? Formation of anthracenes has been noted in several Friedel-Crafts alkylations involving aromatic substrates e.g.9,lO-dimethylanthracene is produced in the preparation of ethylbenzene from benzene and ethylene. The reaction products ob- tained from alkylation system (iv) or where olefins are the alkylating agents would thus also be expected to exhibit paramagnetic resonance absorption due to interaction of the anthracene products with alumin- ium chloride.On the basis of this evidence only suggestion (b) made by Adams and Nicksicl regard- ing the source of free radicals in Friedel-Crafts alkylations can be accepted. Electron-spin resonance measurements were made with a Varian V 4500 spectrometer operating at 9OOO Mc./sec. and a magnetic field modulated at 100 kc./sec. The spectrum obtained from a mixture of anthracene aluminium chloride and chloroform is shown in the Figure together with the spectrum obtained for system (i) in the absence of air; the spectrum obtained with system (ii) was similar to that for (i) but the radical concentration was lower. -H Electron-spin resonance spectra :(A) anthracene + aluminium chloride f chloroform in the absence of air and (B) benzene -l-aluminium chloride -l-benzyl chloride in the absence of air.The aluminium chloride was prepared from the elements and the organic reagents were rigorously purified before use. (Received October 29th 1964.) * (L.F.F. and L.H.S.) The Donnan Laboratories University of Liverpool Vine Street Liverpool 7 (R.E.B. R.N.H., and P.N.P.) The Chemistry Department Faculty of Technology University of Manchester Manchester 1. 1 J. Q. Adams and S. W. Nicksic J. Amer. Chem. SOC.,1962,84,4355. R. E. Banks R. N. Haszeldine and P. N. Preston unpublished work. J See references quoted by E. de Barry Barnett in “Anthracene and Anthraquinone,” Bailliere Tindall and Cox London 1921 p. 15 and A. T. Balaban and C. D. Nenitzescu in “Friedel-Crafts and Related Reactions,” ed.G. A. Olah Interscience New York 1964 Vol. 11 Part 2 p. 979. 4 J. J. Rooney and R. C. Pink Proc. Chem. Soc. 1961 142. DECEMBER 1964 397 [14]Annulene and [18]Annulene Dependence of Nuclear Magnetic Resonance Spectra on Temperature By Y. GAONI F. SONDHEIMER, A. MELERA and R. WOLOVSKY* THEnuclear magnetic resonance (n.m.r.) spectrum of [14]annulene (I)l at room temperature consists of two sharp singlets at r 4.42 and 3.93 (ratio ca. 6 1) due to the presence of two conformers (isomers A and B).3The T 4.4 band (isomer A) undergoes funda- mental changes when the solution is coo1ed.t It broadens progressively; e.g. at -20" the half-height width (h.h.w.) is ca. 60 C.P.S. versus ca. 3 C.P.S. at +20". At -30" the T 4.4 peak can no longer be recognised but at -40" a very broad new band at ca.r 2.7 appears. This new band becomes less broad on further cooling and is found to be associated with a second new band in the T 10 region (this latter peak can best be observed when tetramethylsilane is omitted). At -60" the spectrum consists of broad peaks at T 2.4 (h.h.w. ca. 25 c.P.s.) and r 10.0 (h.h.w. ca. 40 c.P.s.) due to isomer A as well as the T 3.9 peak (which had broadened slightly) due to isomer B. Crystalline [14]annulene shown to consist of isomer A at -60" gave the same spectrum as the equilibrium mixture but without the T 3.9 peak. The r 2.4 band in the -60" spectrum of [14]an- nulene (isomer A) is assigned to the ten outer protons and the T 10.0 band to the four inner protons.This assignment is confirmed by the integrated areas of the two bands which were found to be in the ratio of ca. 5:2. The low temperature n.m.r. spectrum of [14]annulene (isomer A) is typical of that of an aromatic substance showing the existence of a ring current which deshields the outer protons and shields the inner protons. This observation is compatible with the fact that [14]annulene complies with Hiickel's rule. The n.m.r. spectrum of [18]annulene* at room temperature consists of two broad bands at ca. r 1.1 and 11 -8(ratio 2 1 corresponding to the outer and inner protons respectively) providing evidence for the aromatic nature of the substance. It has now been found that these peaks become progressively sharper and exhibit fine structure as the solution is cooled.In addition the separation between the bands is in-creased. Thus at -6O",the low-field signal appears as a quartet-like multiplet centred at T 0.72 and the high-field signal as a complex multiplet centred at r 12-99 (ratio 2 1). The increased separation of the bands at low temperature is indicative of an in- creased ring current. This is in accord with the con- clusion reached from an analysis of the variation with temperature of the diffraction pattern that the equilibrium displacement of the atoms from the mean molecular plane decreases with decreasing tem- perat~re.~ Heating a solution of [18]annulene causes the bands at r 1.1 and 11.8 to broaden and at 40" these bands can no longer be recognised.At 60",a very broad peak at ca. r 4.6 appears which sharpens as the temperature is increased; e.g. the h.h.w. at 80" is ca. 30 C.P.S. and at 100" ca. 10 C.P.S. At 110" the spectrum consists of a relatively sharp singlet (h.h.w. ca. 5 c.P.s.) at T 4-55. The changes with temperature observed for the spectra of both [14]annulene and [18]annulene were found to be reversible. It appears therefore that the n.m.r. spzctra of [14lannulene (isomer A) and [18lannulene are similar in type except that the transition from the "aromatic" two-band spectrum to the single-band spectrum occurs at considerably lower temperature in the case of [l.l]annulene. The most likely explana- tion for the singlet at higher temperatures in each substance lies in the fact that at the higher tempera- ture the protons change position at such a rate that an average value results for the band location.In fact the position of the singlet in each substance is close to that calculated by taking the weighed average of the outer and inner proton band locations. In agree-ment with this explanation is the observation that the ultraviolet and visible spectra of both substances * (Y.G.,F.S. and R.W.) Daniel Sieff Research Institute Weizmann Institute of Science Rehovoth Israel (A.M.) Research Laboratory Varian A.G. Ziirich Switzerland. (Present address of F.S.) University Chemical Laboratory Lensfield Road Cambridge. t The n.m.r. spectra were measured on a Varian A-60 spectrometer tetramethylsilane being used as internal standard (7 10.00).The spectra of [14lannulene were determined in deuterochloroform and those of [18]annulene in perdeutero- tetrahydro furan. F. Sondheimer and Y. Gaoni J. Amer. Chem. Soc. 1960 82 5765; J. Bregman Nature 1962 194 679. L. M. Jackman F. Sondheimer Y. Amiel D. A. Ben-Efraim Y. Gaoni R. Wolovsky and A. A. Bother-By J. Amer. Chem. SOC.,1962,84,4307; F. Sondheimer Pure Appl. Chem. 1963,7 363. Y. Gaoni and F. Sondheimer Proc. Chem. SOC.,1964,299. F. Sondheimer R. Wolovsky and Y. Amiel J. Amer. Chem. SOC.,1962 84 274. ri J. Bregman private communication. were essentially unchanged throughout the tempera- ture range in which the n.m.r. spectra were deter- mined. The compounds therefore presumably possess a ring current even in the temperature range in which the n.m.r.spectra show only a single peak. PROCEEDINGS Thus the existence of a single n.m.r. band in the “non-aromatic” region cannot be considered as evidence for lack of aromaticity unless it is shown that there is no change on cooling. (Received October 23rd 1964.) Catalytic Acitivity of Reduced Platinum-Ruthenium Oxides By G. C. BOND and D. E. WEBSTER* MIXEDrhodium-platinum oxides prepared by a modification of the well-known Adams method after reduction with hydrogen under mild conditions yield catalysts having properties not possessed by either constituent a1one.l By a similar procedure we have prepared platinum-ruthenium oxides many of which on reduction give catalysts of surprisingly high Reactant Solvent Reactant Concn.(M) activity in certain hydrogenation reactions. Tests were performed by shaking 10-50 mg. of the mixed oxide with 20 ml. of an alcoholic (generally meth- anolic) solution of the reactant at 30°c a Griffin laboratory shaker being used hydrogen consump- tion was measured at constant pressure. The results for nitrobenzene and o-nitroaniline are Wt. of oxide E.F. Optimum Ru content 2-Methylbut-3-yn-2-oIb MeOH Maleic acid MeOH Cyclohexene MeOH Cyclohexanone Et OH-HCl Acetophenone MeOH-HC1 Pyridine MeOH-HCI 0.8 1.8 1.5 0-5 3.4 0.25 (mg.) 10 50 10 50 50 so (atomic-%)“ 2.5 3 2.5 20 3-0 30 3.5 30 3.0 30 1.5 3 Reduced to corresponding secondary alcohol.0 10 20 30 40 50 6C Atom-%of Ru (as%of total metal) 0Hydrogenation of 0.6~-nitrobenzene in methanol 10 mg. of catalyst (to aniline). Hydrogenation of 0.Ghil-o-nitroaniEirze in ineth- nnol 20 nig. of catalyst (to o-phenylenediamine). Approximate Ru content as atom-:< of total metal at which rate is a maximum. Products not analysed. shown in the Figure details of the test conditions are given in the legend. The “enhancement factor” (E.F. defined as maximum rate/rate for PtO,) is about 4 for nitrobenzene and 2 for o-nitroaniline. Further results are summarised in the Table. The E.F. and the composition at which the maximum rate occurs varies quite widely from one reactant to another. No variation in the rate of hydrogenation of benzene with composition was observed.The nature of the reduced catalysts has not yet been fully explored but there is indirect evidence that the metals are alloyed rather than being in admix- ture. RuO is not reduced under the conditions used yet the mixed oxides are readily reduced to highly active catalysts mechanical mixtures of PtO and RuO on reduction are not highly active. Variations in surface area cannot alone account for the ob-served results which show greatly different activity- composition curves. Effects due to the electronic interaction of the reactant molecules with the catalyst surface are probably being exhibited and we hope that the more detailed study of this system now in progress will illuminate the relevance of the electronic constitution of alloys to their catalytic properties.(Received November 9th 1964.) * Johnson Matthey and Co. Ltd. Research Laboratories Exhibition Grounds Wembley Middlesex. S. Nishimura and H. Taguchi Bull. Chew. SOC.Japnn 1963 36 353 and preceding papers. DECEMBER 1964 399 A New Sugar Orthoformate By E. J. HEDGLEY and 0. MBRBsz* RECENTpublications report the occurrence of novel stru~turesl~~ and suggest possible synthetic applica- tion~~~* of carbohydrate orthoesters. We therefore report the isolation and characterisation of 1,2-0- isopropylidene -3,5,6 -0 -methylidyne -a -D -glucofuranose (I). This compound will be recognised as the unique? orthoester formally derived by the condensation of one molecule of (tridentate) mono- isopropylidene-D-glucose (11) with one of formic acid.The structure of (I) without precedent among sugar orthoformates is analogous to that of the monothio-orthocarbonate newly encountered by Shasha and his co-workers.2 A solution of monoisopropylidene-D-glucose(11) in dimethylformamide and pyridine reacted on addi- tion of toluene-p-sulphonyl chloride to give (I) which separated from the cooled solution as plates1 (70%) m.p. 201-203" [aID-40-9" (in CHCl,) exhibiting no hydroxyl absorption in the i.r. spec- trum. The expected toluene-p-sulphonate was not isolable. A product identical with (I) was also ob- tained when an ethanolic suspension of the trio1 (11) was treated at room temperature with ethyl ortho- formate catalysed by boron trifluoride etherate.This evidence considered with molecular weight data provided initial confidence in the correctness of the four-ring structure suggested for (I). The structure is unequivocally established by the n.m.r. spectrum of (I) (in deuterated chloroform) which shows a signal for the trioxymethine proton at r 3-99 (singlet) slightly upfield from that for the anomeric proton centred at r 3-90 (doublet). At room temperature the orthoformate (I) has a low solubility in water and a range of common organic solvents. It is characteristically very resistant to alkaline hydrolysis but undergoes ready hydro- lysis in acid to yield a mixture of products which depending on conditions can include partially formylated or unsubstituted monoisopropylidene- D-glucose and (ultimately) D-glucose itself.Specula- tion on the structure(s) probable for a partially formylated monoisopropylidene-D-glucose,arising from (I) by hydrolysis was influenced by considera- tion of the generally accepted principles governing acyl migration in carbohydrate system^.^ The pre- ferential formation of 6-O-formyl-l,2-0-isopropyli-dene- a-D-glucofuranose (111) was therefore expected. From a sample of (I) by partial hydrolysis the formate (111) was isolated (recrystallisable from benzene) m.p. 98-lOO" [aID-3.5 (in CHC13) (Found C 48.5; H 6-5;0,455. CloH,,O requires C 48.4; H 6.5; 0 45.1%). Supported by n.m.r. spectral data,§ an unambiguous proof of the struc- ture of the new ester was obtained as follows.h (n R=H) (m R=formyl) Me By conventional means (111) was converted into the amorphous acetal3,5-0-benzylidene6-0-formyl-1,2-0-isopropylidene- a-D-glucofuranose (IV),which when deformylated in alkali gave crystalline 3,5-0- benzylidene -1,2 -0-isopropylidene -a -D -gluco-furanose (V) m.p. 149-150" [aID + 23.2" (in CHCI,). The product (V) had constants in close agreement with those previously reported for this cornpound,6y7 and was identical with a specimen obtained by alkaline deacylation of 6-0-acetyl-3,5- 0 -benzylidene -1,2 -0 -isopropylidene -a-D -glucofuranose,6 prepared by adaptation of Bell's method. (Received October 26th 1964.) * Department of Chemistry Birkbeck College London W.C.1.t The methylidyne group is asymmetric but formation of the diastereoisomer of (I) is sterically precluded. $ Found C 52.5; H 6.4; 0,41-4. C,,H,,O requires C 52.2; H 6-1; 0,41.70/,. 0 E.g. in deuterated chloroform the formyl proton showed a signal at T 1.81 (singlet) characteristically at lowest field and the anomeric proton a signal centred at T 4.02 (doublet). C. S. Giam H. R. Goldschmid and A. S. Perlin Canad. J. Chem. 1963 41 3074. B. S. Shasha W. M. Doane C. R. Russell and C. E. Rist Nature 1964 204 186. J. Zemlicka Chem. and Ind. 1964 581. C. B. Reese and J. E. Sulston,Proc. Chem. Soc. 1964 214. -,E. Pacsu Adv. Carbohydrate Chem. 1945 1 109. P. Brig1 and H. Gruner Ber. 1932 65 1428. P. A. Levene and A. C. Raymond Ber.1933 66 384. D. G. Bell J. 1936 859. PROCEEDINGS The Crystal Structure of p-Sb204 A New Polymorph By D. ROGERS and A. C. SUPSKI* THEnormally available form of Sb204is an ortho- rhombic powder or the mineral cervantite;l we shall call this ar-Sb204. For lack of suitable single crystals its structure has had to be inferred from that of stibiotantalite (SbqaVOJ with which it is iso- morphous? A new form which we designate p-Sb,04 is produced by heating a-Sb204 in air or oxygen. It is probably formed in the following manner 2a-Sb2O4-f Sb40 + O2 + 2p-Sb204. (solid) WPOW (solid) O$ +f q2 -A (b) I l-2 i a -a (a) 7! 4 I '-4 FIG.1 (a). [001] projection of P-Sb2O4showing cor-rugated layers of Sbv octahedra and Sb'II columns trapped between them.Sb'CO bonh are marked (short) and -- - (long). (b). View from C looking toward A B in Fig. la. hyer B of octahedra contributes oxygens (0)to column A of SbIn. Oxygens (0) are contributed by octahedra in layer C,which is related to layer B by the diads passing through the Sb". The best-textured specimens were obtained by heating a-Sb204to about 113O"c in a stream of dry oxygen. P-Sb2O4 is stable in oxygen up to 1006 lo" and in air to 933 f10". + 2.218 sbm(b) FIG.2 (a). Sbv co-ordination.(b). Sbm co-ordination. (Standard deviation of bonds is 4.009 A and of angles is 4.4 A.) a = 148.1"; ,8 = 87.9"; y = 88.7"; 6 = 89.8"; E = 95.7". The crystals are monoclinic prisms elongated along c with (100) prominent but the habit is slightly variable according to the temperature of formation.All are polysynthetically twinned on (100) with 6 c in common. Unit-cell data obtained from a combination of single-crystal measurements and least-squares calculations on data from Guinier and 19-cm. powder photographs are a = 12.060 f 0.003 b = 4.834 f0.002 c = 5.383 f0.002 A, 18 = 104" 35' f2' u = 303.7 f0.3 A3 Dabs. 6-73 g.cm.4 Dcalc. = 6.72 g.~m.-~ for a cell con- tent of 4(Sb@4). Systematic absences indicate the space group is Cc or C2/c:the latter has emerged as the relevant one. The structure has been determined from some 420 (hkl)reflections recorded with Mo-K radiation and visually estimated. It has been refined using isotropic temperature factors to R = 0.066.Figures la and b show that the two Sb species have very different environments. The Sbv atoms occupy centres of symmetry and each is surrounded by a slightly distorted octahedral set of oxygen atoms (see also Figure 2a). The SbnI atoms lie on diad axes and have a very one-sided co-ordination (see Figure 2b). A similar co-ordination occurs3 for Bi in BiWbvO (which is isomorphous with p-Sb20,) @.It.) Chemistry Department Imperial College London S.W.7 (A.C.S.) Present address Institute of Inorganic Chemistry University of Stockholm. 1 W. Grunder H. Patzold and H. Strunz Neues Jahrb. Min. 1962 5 93. a K. Dihlstrom 2.anorg. Chem. 1938,239 57. * B. Aurivillius Arkiv Kemi,1951 3 153. DECEMBER 1964 and for As'*' in potassium di-o-phenylenedioxy- arsenate(IrI) K [As(C,H,O,),].~ The octahedra are linked by sharing corners to form corrugated sheets parallel to (100).Adjacent sheets are joined by the A. C. Skapski to be published. SbI" atoms. The polysynthetic twinning is explicable in terms of occasional mistakes in the stacking of the layers of octahedra. (Received October 19th 1964.) A Cyclic Acetylene Complex of Hexacarbonyldicobalt (CO)3CoC6F6Co(CO) By N. A. BAILEY,M. R. CHURCHILL, R. HUNT,R. MASON,and G. WILKINSON* THE reaction of octacarbonyldicobalt CO,(CO)~ with octafluorocyclohexa-l,3-dienegives in 14% yield a complex of molecular formula (OC)3CoC,F,Co(CO)3 (np. 47-48 "). The infrared spectrum in cyclohexane shows carbonyl stretching frequencies at 2120 2086 and 2062 cm.-l with a further prominent absorption at 1672 cm.-l (C-C).The 19F nuclear magnetic resonance spectrum (in benzene) shows four bands details of which are summarised in the Table. P.p.m. up- Relative Total width field from area (c./sec.) Cf3HdCF3 Band 1 36.2 2.0 31 Band 2 51.0 2.0 58 Band 3 59.1 1.0 37 Band 4 89.6 1-0 62 All the bands are multiplets symmetric about the centre of the band and containing at least nine peaks. This spectroscopic data suggested a formulation of the complex involving an isomer of perfluorobenzene that is a perfluorocyclohex-1-yn-3-ene group (I) and a three-dimensional X-ray analysis (R = 0.09) con- firms this assignment. The complete molecular stereochemistry is shown in the Figure.The two cobalt ions separated by 2.471 A are bridged by the formally acetylenic bond (1.29 A); the two sets of terminal tricarbonyl groups are in an eclipsed con- formation the average Co-C(0) distance being 1.81 f0.03 A. The bond angles within the carbocyclic ring are all remarkably close to 120". There are close similarities between the present structure and those of octacarbonyldicobaltl and hexacarbonyldiphenylacetylenedicobalt.2 The di-hedral angle between the bridging group and the Co-Co bond direction is 87" in the present example and 88" in Co,(CO),C2Ph,. The average Co-C (acetylene) bond length of 1-96 A in Co,(CO),C,Ph is however greater as is the formal triple bond length (1.46 A).In Co,(CO),,the Co-Co bond length is 2.52 A a value which is significantly greater (40) than the present result despite the fact that the essential geometry of (OC)3CoC,F,Co(CO)3 is one in which the two bridging carbonyl groups in CO,(CO)~ are replaced by the one bridging C,F moiety. This replacement presumably serves to modify the effective nuclear charge and hence the radii of the cobalt ions. As such the results are identical to those in other molecules containing metal -metal bonds -for example Hg,F (Hg-Hg 2-43 A) Hg,CI (2.53 A), Hg,Br2 (2.58 A) and Hg,I (2-69 (Received October 15th 1964.) (N.A.B. M.R.C. R.M.)Department of Chemistry The University Sheffield (R.H. and G.W.) InorgaHic Chem- istry Research Laboratories Imperial College ,London.G. G. Sumner H. P. Klug and L. E. Alexander Acta Cryst. 1964 17 732. W. G. Sly,J. Amer. Chem. SOC.,1959 81 18. A. F. Wells "Structural Inorganic Chemistry," 3rd edn. Oxford University Press 1962 p. 891. PROCEEDINGS Boron-11 Nuclear Magnetic Resonance Spectra of Two Boron Hydride Derivatives at 60 Mc./sec. L. PILLING M. FREDERICK and EUGENE By RICHARD FREDN. TEBBE HAWTHORNE A. PIER* -11.3 p.p.m. ponding to the 3(6) 8(10) 9(12) and 4(5,7,1 I) atoms d should be in the ratio of 2:2:2:4. Although it is not +35.8 apparent in the llB n.m.r. spectrum obtained at 1In 19.3 Mc./sec.’ that four distinct types of borons are d f I DECEMBER 1964 present all of the expected peaks can be distinguished in the more highly resolved spectrum at 60.0Mc./sec.(Fig. 2). Three doublets of relative intensity 2 appear from low to high field at positions a 6 and d. The doublet of intensity 4at c centred between the b and d positions can be unambiguously assigned to the four structurally equivalent' 4(5 7 11) atoms. The high resolution spectrum is therefore consistent with the known structure although it does not by itself provide a unique structural solution. If the relative chemical shift values are used to reduce the resolution of the 60.0 Mc./sec. spectrum to the 19-3 Mc./sec. level the doublets a and b coalesce so that the high- field member of a and the low-field member of b are nearly superimposed. Thus the two low-field lines in the reported spectrum7 are members of an apparent 1 :2 1 triplet formed by partial overlap of a pair of doublets.At the lower frequency the doublet at b is nearly centred on the low-field member of c and the doublets at c and d are so closely overlapped as to be indistinguishable. The effects of selectively substi- tuting for hydrogen groups not coupled with boron can be estimated for the 60 Mc./sec. spectrum. The 60 Mc./sec. spectrum therefore can provide a guide for completing the assignment of peaks in carborane spectra obtainable at lower frequencies. (Received August 3 lst 1964.) The Effect of Heat on Some Di(a1kylamino)phenylphosphhes By A. P. LANEand D. S. PAW* THE recent publication of details of &he investigation of the deamination of di(a1kylamino)dimethylsilanesl prompts us to report similar work with alkylamino- phosphines.In an attempt to prepare further cyclic aminophosphines2 the thermal deamination of a series of di(alkylamino)phenylphosphines PhP(NHR), (R = Me Et Pri and But) has been investigated. Experiments with R = Me led to the loss of methylamine and the formation of poly-phenylphosphine (PhP), together with a complex mixture of high molecular weight material. However in the case of the ethyl and isopropyl compounds the products after heating in sealed tubes at 140-160" for periods from 24 to 120 hr. comprised a mixture of unchanged starting material free amine some condensed material of indefinite composition con- taining a number of PhPNLNR units a monophos- phazene PhP(NHR) =NR and tetracyclo(pheny1- phosphine).The reactions can be represented 2PhP(NHR) -NR:PPh(NHR) + '/4(PhP)d + RNH 2PhP(NHR) --t PhP(NHR)-NR.PPh(NHR) + RNH etc. The amount of aminophosphine converted into phosphazene did not exceed about 20% of the original phosphine for the ethyl analogue and 12% for the isopropyl. The l-alkyl-2,2-di(alkylamino)-2-phenylphosphazenes are white crystalline solids very susceptible to hydrolysis which leads to the corresponding oxide PhPO(NHR) and free amine. The isopropyl derivative was readily purified by sublimation at 110-1 150/104 mm. (m.p. 135-138") (Found C 63.9; H 10.1; N 15.0; P 11.0. C15H28N,P requires C 64.0;H 10.0; N 15.0; P 11 SO%). The ethyl derivative was more difficult to purify; however an impure sample (m.p.110-122") proved to be monomer in benzene. The presence of more highly condensed material in the case of the iso- propyl compound was demonstrated by the ozonisa- tion of the products. after removal of the almost in- soluble phosphazene to yield a small amount of di(isopropylamin~phenylphosphiny1)isopropylamine monohydrate [PhP(NHPrl)O] NPri,H,O identified by analysis and infrared spectrum. No more com- plex condensation products have yet been identified. In the case of the t-butyl compound the product did not contain polyphenylphosphine and the phos- phazene although produced was present to a much lesser extent. Thus the thermal deamination of di(alky1amino)- phenylphosphines is not readily accomplished; instead a rearrangement occurs which leads to a monophosphazene.It is suggested that the reaction involves a transfer of an RN group from one phos- phorus to another perhaps by a free-radical mechan- ism; the resulting alkylaminophenylphosphine then loses amine to give the tetracyclo(pheny1phosphine) 2PhP(NHK) -RN:PPh(NHR) + PhPH(NHR) PhPH(NHR) +l/a(PhP)* + NHzR (where R = Et and hi). (Received October 9th 1964.) * Chemistry Department The University Glasgow W.2. E. W. Abel and R. P. Bush J. fnorg. Nuclear Chem. 1964,26 1685. a E. W. Abel and G. Willey Proc. Chern. Soc. 1962 308. PROCEEDINGS Non-flexible Vinyl Polymers in Solution By J. HUGHES and A. M. NORTH* No studies have yet been reported which compare the solution properties of a certain flexible coiled molecule with rigid random coils of the same mole- cule.That such a comparison is possible in an experimentally practicable temperature range must follow from the hypothesis that the restriction of polymer backbone motion causes the decreased rate of free-radical termination in low-temperature photopo1ymerisations.l In order to test the hypo- thesis we have examined the kinetics of the low- temperature photopolymerisation of vinyl bromide (which leads to a flexible chain) of methyl methacryl- ate (a rather stiff chain) and of N-vinylcarbazole (a very stiff chain) and have determined the tempera- ture dependence of viscosity of poly(methy1 meth- acrylate) and yoly-A’-vinylcarbazole solutions.Values of the radical-radical termination rate constant (in the case of vinylcarbazole the ratio of the termination and propagation rate constants) are presented in Figure 1. The increased activation energy I I I 0.40 -\ d -(Lo-o-& -0.35- -7030 I ii U 1 I 4.0 o,J 0.25 3.0 35 45 IO?;r P’ I FIG.1. Plot of 2kt or 2kt/kp against 1/T. a Vinyl bromide b N-Vinylcarbazole c Methyl methacrylate. -50 0 + 50 for low-temperature termination of the stiff chains is (“c) apparent. The lack of curvature in the corresponding FIG.2. Plot of intrinsic viscosity against temperature. plot for vinyl bromide confirms that the phenomenon d Poly-N-vinylcarbazole (A4 ca. 80,000)in tetra-is not due to some inexplicable error introduced by hydrojuran.e Poly(methy1 methacrylate) (M 9.1 x the experimental technique. The rate constants were 104) in ethyl acetate. f Poly(methy1 methacrylate) (A4 measured by conventional techniques of intermittent 1.4 X lo6)in ethyl acetate [y] X 10-l. * Donnan Laboratories University of Liverpool Liverpool England. J. Hughes and A. M. North Trans. Farahy SGC.,1964,60 960. M. Kryszewski Roczniki Chem. 1957 31 147 893. DECEMBER 1964 times were measured 15-20 minutes after adding liquid to the viscometer.) In the case of poly(methy1 methacrylate) a sharp transition is observed in the temperature range predicted by the kinetic experi- ments. Poly-N-vinylcarbazole shows a minimum in the intrinsic viscosity-temperature curve in a temperature region higher than the transition region of the kinetic experiments.The reason for this prob- ably lies in the fact that the monomer polymerises slowly at these temperatures and that radicals of low molecular weight (for which this effect would be less pronounced) predominate in the termination re-action. The viscosity transition temperature is thus more relevant to a discussion of the solution pro- perties of long chains. The intrinsic viscosity of poly-N-vinylcarbazole solutions below 0"c is very dependent on the solution history. Lower values are obtained after slower cool- ing and higher values are obtained from solutions with a history of subjection to shear stress. This apparent stabilisation of the metastable conforma- tions produced under shear is being studied in greater detail in these laboratories.Thus studies of the polymerisation of vinyl bromide and N-vinylcarbazole confirm the existence of a low-temperature transition in the termination reactions of stiff polymeric radicals but not in those of flexible chains. The occurrence of a related transi- tion in the intrinsic viscosity of these polymers seems to be the first reported observation of the random flexible coil-random rigid coil transition in dilute solution. (Received November 2nd 1964.) Equilibria between Carboxylic Acids and Stannic Chloride and the Brnrnsted Acidity of such Dual-acid Systems By D. P. N. SATCHELL and J. L. WARDELL* DUAL-ACID systems such as carboxylic acid-stannic chloride-aprotic solvent are important in Friedel- Crafts catalysis.They possess enhanced Bronsted acidity and are unusual in that the most acidic systems from this viewpoint are provided by those carboxylic acids which are the weakest in hydroxylic media.l Equilibria (1)-(3) are expected and on addi- tion of a basic indicator (B) which is not affected by the stannic chloride or the carboxylic acid separately Brsnsted acidity may be determinedl by means of equilibria like (4). Kl 2 R*CO,H + (R*CO,H) (1) K2 R-CO,H + SnC1 +HSnC1,OCORt (2)# K3 2R-C02H+ SnC1 +H,SnCl,(OCOR),t (3)$ K4 H,SnCl,(OCOR) + B + [BH J+[HSnCI4(0COR),]-(4) It is (4) and any similar equilibria which are the real measures of the strengths of the complex acid species.The amounts of these species present and therefore the observed acidity of a given dual-acid system is also controlled by (2) and/or (3). We have now been able to separate these factors. We have measured K, K2 and K3 by infrared spectroscopy and K by ultraviolet spectroscopy using as B o-nitrodiphenylamine. K was always negligible compared with K, and H,SnCl,(OCOR) behaved essentially as a monobasic acid as in (4). Some values of K3 and K4 are in the Table together with the aqueous dissociation constants K of RC0,H. Equilibrium constants for RC0,H. (Concn. units moles/l. ;solvent o-dichlorobenzene) R 1OW3K3 (28") K4 (25") K (25") But 69 Bun 52 Bu' 44 Et 27 Me 12 PhCH 9.8 CH,CI*CH2 0.90 CH&l 0.056 64 8.9 x 73 1.5 x lo-' 57 1.4 x 10-5 -1.3 x 10-5 83 1.7 x 63 4.9 x 10-5 129 1.0 x lo4 200 1.4 x lo4 The variations of K3(which roughly but inversely parallel the variations in K) are explicable in terms of the known substituent effects of the groups R.K4 varies by a factor of c 4 while K varies by a factor of > 150. This striking result shows that the strengths of the complex acids are insensitive to the structure of their Bronsted components and means that the acidity in these systems is largely controlled by (3). This result supports our empirical rule concerning such systems.l K3 and K4have not previously been evaluated for any Lewis-carboxylic acid pair. That K2 is negligible is exceptional. With no other ligand so far studied is this true for stannic chloride adducts.(Received October 13th 1964.) King's College Strand London W.C.2. 7 This conventional representation is not intended to indicate any particular structure. $ Equilibria (2) and (3) may be written alternatively in terms of (RC02H)2. D. P. N. Satchel1 and J. L. Wardell Pruc. Chem. Suc. 1962 296. J. J. Myher and K. E. Russell Cunad. J. Chem. 1964 42 1555. PROCEEDINGS Solvolysis of Alkyl Chlorosulphates A Possible Multiple Bond Fission Solvolytic Reaction E. BUNCEL and J. P. MILLINGTON* ALKYLCHLOROSULPHATES RO.SO,Cl are struc-turally related to other acyl halides which can react by alkyl-oxygen or acyl-halogen bond fission e.g. alkyl chlorosulphites or chloroformates.Very few studies of chlorosulphates have been reported.lP2 We have investigated the series RO-S02CIwhere R = methyl ethyl n-propyl isobutyl and neopentyl under solvolytic conditions. In 10waqueous dioxan product analysis of dilute solutions shows that the stoicheiometry of the reaction is RO.SO,Cl + 2H20 --t ROH + H2SO4 + HC1 (1) The formation of t-pentyl alcohol from neopentyl chlorosulphate shows the onset of a carbonium-ion mechanism with this member. When the activation parameters (Table 1) are compared with those of other solvolytic reactions in the same reaction medium ii becomes apparent that chlorosulphate solvolysis is associated with a more positive AS$,by 10-15 e.u. in unimolecular as well as in. bimolecular solvolysis.t TABLE 1 .Rates and activation parameters-for solvolysis of‘RO.SO,CI in 1Owaqueous dioxana R 104k (25°)b (sec.-l) AHS~ (kcal./mole) AS$ (25°)b (e.u.) Me 21 1 13-8 -20-0 Et 71.6 12-6 -26.0 n-Pr 39.8 13.6 -24.0 i-Bu 3.09 17-6 -15.5 neo-Pe 0-168 24.0 0.1 a Rates measured conductometrically. Error in k is f1%; in AH$ f0.35 kcal.; in AS$, f1.0e.u. The relative reactivities (Table l) the lyate-ion effect and the effect of added ~iucleophiles~ in chloro- sulphate solvolysis are entirely consistent with a normal solvolytic mechanism which can be uni- molecular or bimo!ecular with the leaving group being -O.SO,Cl (cf. ref. 2). On this basis the transition state for the unimolecular mechanism would be as shown in (1). The solvation of (I) would not be expected to differ significantly from that of R -0-SO2 -C1 R -0402 -C1 (1) (11) the corresponding transition state in arenesulphonate solvolysis from which one would expect similar ASS values but this is not the case.The alternative transition state (11) with its greater charge separation would be more strongly solvated leading to a more negativeASS but the simultaneous weakening of two bonds leading to the formation of three fragments would result in an increased AS$due to the gain of vibrational and rotational degrees of freedom. In gas-phase reactions abnormally high ASS values by 10-20 e.u. are believed to be due to simultaneous rupture of two bonds.* The fragmentation process in chlorosulphate solvolysis may therefore well result in abnormally large entropies of activation.The transition state in chlorosulphate solvolysis is hence represented by the following resonance structures R+-O-SO2-C1 R+ OSO2 C1-R-O-S02+ Cl-The hypothesis of the fragmentation process in chlorosulphate solvolysis is pertinent to the problem of the possible generality of multiple bond fission. The solvolysis of alkyl chloroformates in formic acid appears to be associated with an unusually high ASS ethyl and isopropyl chloroformates have ASS values of -1-8 and -0.4 ex. respectively.D In con-trast formolysis of the corresponding arenesul- phonates proceeds with more negative AS$ by 5-15 e.u.lo It is therefore noteworthy that in the solvolysis of alkyl chloroformates there is evidence of both alkyl-oxygen and acyl-chlorine bond fi~sion.~,ll A recent study12 of an SNireaction the de- composition of arylalkyl thiocarbonates ROCO.SR’ to RSR’and CO,,has provided evidence for simul- taneous fission of the alkyl-oxygen and acyl-sulphur * Department of Chemistry Queen’s University Kingston Ontario.Typical cases of unimolecular solvolysis are t-butyl chloride (ASS = -12.7 e.u. AH$ = 21 -9 k~al.)~ and isopropyl benzenesulphonate (ASS = -14.6 e.u. AH$ = 22.4 kcal.),J and of bimolecular solvolysis ethanesulphonyl chloride (ASS = -37.4 e.u.. AH# = 12-8 k~al.).~ More than a dozen examples are available in refs. 3-6. Jennings and Jones Canad. J. Chem. 1963 41,1151; Jones Perry and Turner Ibid.,1960 38,1122. a Hall J.Amer. Chem. SOC.,1956 78. 1450. Winstein and Fainberg J. Amer. Chem. SOC.,1957 79 5937. Tommila and Merikallio Suomen Kem. 1953 26 B 79; Tommila Acta. Chem. Scand. 1955 9 975. ti Foon and Hambly Aust. J. Chem. 1962 15 668. Fainberg and Winstein J. Amer. Chem. SOC.,1957 79,1597 1602; Winstein Fainberg and Grunwald ibid. 1957 79 4146. Buncel and Millington unpublished work. * Gowenlock Qucrrl. Rev. 1960 14. 133; Steel and Laidler J. Chem. Phys. 1961 34 1827. Grunden and Hudson J. 1961 3748. lo Winstein and Marshall J. Amer. Chem. SOC.,1952 74 1120. l1 Green and Hudson J. 1962 1076. l2 Kice and Bartsch Tetrahedron Letters 1963 25 1693. DECEMBER 1964 bonds through the observation of specific electronic effects of R and R’ on the rate of reaction.No entropies of activation were reported for the reaction. In view of the many factors which can influence entropies of acti~ation,~,~~~~~ further entropy data for SNiand other solvolytic processes are needed and corroboration by other criteria which allow a direct measure of the extent of bond weakening is desirable for between Processes. full evaluation of the relationship and multiple bond fission in solution (Received September 25th 1964.) Schalager and Long Advances Phys. Urg. Chem. 1963,1 1. l4 Kohnstam “The Transition State,” p. 179 Special Publ. No. 16 The Chemical Society London,1962. Fluorine Nuclear Magnetic Resonance Spectraof Hydroxyfluorostamates By P.A. W.DEAN and D. F. EVANS* M SnF,2- ion is well characterised both in the solid state and in solution and solid compounds of the type M*SnF,.0H,1s2 MiSnF,(OH),,2 and MiSnF2(OH)42 have been reported.Solid MiSnF,(OH) could not be obtained and this was attributed to the high stability of MXSnF2(OH)4.2 From the fluorine resonance spectra of aqueous solutions of (NHJ2SnF in the presence of ammonia ingly the two spectra can be assigned to truns-and ~is-SnF,(oH),~- respectively. The l17Sn andllg Sn satellite bands of each were consistent with this interpretation. Finally at high pH (> 7-5) another single sharp line and an AB,spectrum also appeared showing the formation of sym-and asym-SnF,(OH)32-. The relative areas (1 -2-0) were again independent of pH. Fluorine chemical shifts (to high field of CF,.CO,H as external reference) and spin-spin coupling constants.Complex Chemical shift JC17Sn-19F) J(119Sn-19~ JWA-FB) bp-m.) SnF2- 79.3 SnF,0H2- FA 68.6 cis-SnF,(OH) 2- FB FA FB 68.6 60.2 62.6 trans-SnF,(OH):-asym-SnF,(OH) 2- FA FB 58-8 51.4 53.6 sym-SnF,( 53.5 we have been able to characterise unambiguously the ions SnF,-OH*- cis- and tr~ns-SnF,(OH),~- and asym- and sym-SnF3(OH),2- in labile equi1ibrium.f. The species first obtained on addition of ammonia to an aqueous solution of (NH,),SnF gave a slightly broad fluorine resonance line which displayed some structure under high resolution. The l17Sn and l19Sn satellite bands of this resonance showed that it is an AB system with a large value of J/8; clearly the species responsible is SnF,-OH2-.On further addi- tion of ammonia a single sharp line and an A2B spectrum appeared simultaneously. The relative areas (1 :4.3)were independent of pH and accord- (c./sec.) (c./sec.) (c./sec.) 1486 1555 1222 1278 29 1698 1776 1452 1518 32 1750 1820 1870 1956 -37 1553 1605 The cis/trans ratio of 4-3 and the asymlsym ratio of -2.0 are close to those expected on purely statistical grounds (4 and 1.5 respectively). This is not surprising in view of the close simiIarity between the OH and F ligands in size polarisability and electronegativity. Neutral cis- and trans-isomers of stannic fluoride with ethanol and cis-.isomers with organic bases4 have previously been characleriscd by fluorine n.m.r.spectroscopy. The chemical shifts and l9F-l9Fand 1171119Sn-19F spin coupling constants for the various species studied are given in the Table. (Received October 15th 1964.) Inorganic Chemistry Research Laboratories Imperial College of Science and Technology London S.W.7. t Fluorine exchange between these ions and fluoride ion is however slow on an n.m.r. time scale (average lifetime > sec.). S. H. C. Briggs 2.anorg. Chem. 1913 82,441. V. L. Kolditz and H. Preiss 2.anorg. Chem. 1963 325 442. R. 0. Ragsdale and B. B. Stewart Proc. Chem. SOC.,1964 194. * E. L. Muetterties J. Amer. Chem. SOC.,1960 82 1082. PROCEEDINGS The Catalysed Photochemical Isomerisation of Olefms By M. D. CARR,V. V. KANE,and M. C. WHITING* THEdirect and the promoted photochemical stereo- mutation of olefins have received attention recent1y.l Olefins may also be stereomutated and rearranged positionally by the photochemical generation in the same solution of species capable of catalysing their interconversion.We describe two examples of this process reach mechanistic conclusions and draw attention to the advantages of generating reactive inorganic intermediates by using radiation of long wavelengths. Iron dodecacarbonyl (Amax. ca. 6000 A) was irradiated with tungsten light (3400"K filtered to remove radiation below 4400 A) as a 0.0004~-solution in light petroleum (b.p. 3040") in the presence of oct-l-ene at 293"~. The internal octenes were formed in yields as high as 270 mol. The com- position of the initial mixture of products was estimated by gas-chromatographic analysis after various degrees of reaction in the range 4-27 % and linear least-squares extrapolation of relative yields to zero conversion,2 and is shown in the Table (col.1). tion to olefin + Fe(CO),. The equilibration reaction was too slow to follow when cis- or trans-oct-4-ene was the starting material pal tly because of concur- rent photo-decomposition of the carbonyl. Although the complexes olefin-Fe(CO), are easily formulated their interconversion requires the brief existence of other complexes with the iron atom attached to three carbon atoms two non-adjacent carbon atoms or one carbon atom. The last two seem the most prob- able. Similar problems exist for analogous rearrange ments catalysed by noble-metal compo~nds.~ Under our conditions no reaction took place in the dark but various descri bed5 isomerisations of olefins in the presence of iron carbonyls nonphotochemical or not known to be photochemical may involve identical organometallic intermediates (cf.ref. 5c). Iodine is well known to stereomutate complex olefins in solution especially polyenm in the presence or absence of light. Iodine atoms generated thermally6 or photoche~ni~ally~ have been shown to stereomutate the but-Zenes and more slowly to Composition of extrapolated initial isomerisation products Temp. (OK) 293 293 373 373 373 Catalyst Fe3(c0)12 t 12 I2 12 Starting material t-4-ene c-4-ene t-3-ene c-3-ene t-2-ene c-Zene dl d1 -dl c-4-ene dl +c-4-ene 59 82 1 loo* loo* -7 15 0 loo* loo* 7 17 19 17 0 15 97 104 loo* 0 23 27 33 0 --0 * Arbitrary.Isomerisation is non-sequential and indeed the com- position of the kinetically-controlled product-mixture closely resembles that calculated2 for the equilibrium mixture (col. 2). The most plausible mechankm involves photochemical formation of Fe(CO)* addition to oct-l-ene to give a complex analogous to C2H,.Fe(CO),;3 rapid rearrangement to a set of six internal-olefin complexes correspond- ing to the internal n-octenes and-not surprisingly-having equilibrium constants close to those of the parent hydrocarbons; and relatively slow decomposi- t Calculated gas-phase equilibrium mixture omitting A'.equilibrate the three butenes in the gas phase. Trradia- tion (light of 3400"~ at 374"~) of methylcyclohexane solutions of iodine and (a) oct-l-ene (6)cis-oct-4-ene and (c) both olefins (1 :1) effected rearrangements (up to 60 rnol.). The extrapolated initial ptoduct- mixture composition was found as before. The cis-olefin stereomutated about three times as fast as it rearranged ; both rearrangements were cssentially sequential (cols. 3 and 4); the competitive experi- ment (col. 5) gave products in essentially the same ratios as were formed from individual starting * Dyson Perrins Laboratory Oxford University. l G. S. Hammond J. Saltiel A. A. Lamola N. J. Turro J. S.Bradshaw D. 0.Cowan R. C. Counsell V. Vogt and C. Dalton J.Amer. Chem. Suc. 1964 86 3197 and references there cited. M. D. Carr J. R. P. Clarke and M. C. Whiting Pruc. Chem. SOC.,1963 333. a H. D. Murdoch and E. Weiss Helv. Chim. Acfa 1963 46 1588. 4 J. F. Harrod and A. J. Chalk J. Amer. Chem. SOC.,1964 86 1776. ti (a)H. W. Sternberg R. Markby and I. Wender J. Amer. Chem. Suc. 1956,78,5704; 1957,79,6116; (b) F. Asinger and 0.Berg Ber. 1955,88,445; (c)T. A. Manuel J. Org. Chem. 1962,27,3941. 6 S. W. Benson and A. N. Bose J. Amer. Chem. Suc. 1963 85 1385. M. H. Back and R. J. Cvetanovic Canad.J. Chem. 1963,41 1396 1406. DECEMBER 1964 materials and indicated that cis-oct-4-ene rearranged positionally about four times as fast as did oct-1-ene. Traces (-1 % of total product) of octadienes were formed from oct-1-ene.No reaction occurred in the dark at 374”~ in the presence or absence of hydrogen iodide equivalent to the iodine. The ratio of cis- to trans-oct-2-ene formed from oct-1 -ene is near the equilibrium value a result not meaningful in view of the probably much more rapid equilibration of these two isomers which may defeat the approxima- tions implicit in the extrapolation procedure. The ratio of cis- to trans-oct-3-ene from cis-oct-4-ene (0-9) however is much higher than the equilibrium value. In contrast a mechanism involving a planar allylic species e.g. the carbanion is expected to give a ratio lower than the equilibrium ratio because of the steric hindrance in the cisoid cis-conformation; and it does.2 Any route involving direct reduction of a 3,5-allylic radical is therefore ruled out.If however such a radical is assumed to equilibrate with the two iodo-octenes (two stereoisomers each) or if the radical is long-lived enough to stereomutate in- ternally our results become consonant with the American picture6 of the butene equilibration. The more complex Canadian mechanism‘ can also be fitted to them if the formation of the diene is a minor reaction under these conditions; there is no plausible route from octa-1,3-diene to the octenes which allows a ratio of oct-3-ene oct-2-ene as low (0-05)as was observed here. (Received November 2nd 1964.) Copper-catalysed Hydrogen-transfer Reactions By R. G. R. BACON,S. C. RENNLSON, and 0.J. STEWART* WE summarise results of investigations which in ‘*g** extension of miscellaneous obs&ations in the literature e.g.concerning by-products of Ullmann reactions,l demonstrate the occurrence of copper- catalysed hydrogen-transfer from many kinds of donors to specific types of organic acceptors result- ing in substitutive reductions RX 4 RH. Acceptors so far known are halides the response of which varies widely with their structure certain organo- sulphur compounds and diazonium salts. Reactions have been effected e.g. in refluxing dimethyl- acetamide or 2,4,6-collidine with cuprous oxide or copper as preferred catalysts; the compounds CuO Cu,S CuHal CuSCN and CuCN were less effective. (a)Halides.-Two kinds of dehydrogenation were observed in the donors.Type (i) RHal + XH-RH + Hal-+ X (or RHal + XH 4 RH + HHal + X). Thus 1-bromonaphthalene gave naphthalene in yields of up to 90% with alkoxides (p.g. XH-= MeO- EtO- PriO- ButO-) in moderzte yield with sodium formate (XH- = HC02-) and in poor yield with a suitable alcohol (XH = CHPh,-OH). Such reactions may be hydride-ion transfers as was sug- gested2 for reductions of bromonaphthalene by copper (1) salts of carboxylic acids. Type (ii) RHal + XH -RH + HHal + poly-meric products of X (e.g. X-X) or fragmentation products of X Donors included phenols aromatic compounds with’ unsaturated substituents (NO2 CO,Et etc.) quin- ones amines and other compounds with >NH groups. Identified dehydrogenation products were the same as those produced in homolytic oxidations of the donors by transition-metal ions; i.e.these copper-catalysed reductions may involve hydrogen- atom transfer. Side reactions included nucleophilic substitution (RHal -RX) halide coupling (RHal --f R-R) and catalysed autoxidation of the donor. (b) SuIphur compounds.-An example studied was o-NO2.CGHa.SCN + (I) -(o-NO~C,H,.S)~+ (11) 5. (further reaction) (O-NOZ.C,H~)~S (c) Diazonium salts.-It is known3 that reduction of * Department of Organic Chemistry Queen’s University Belfast Northern Ireland. E:g. W. M. Whaley L. Starker and M. Meadow J. Org. Chem. 1953 18 833; H. E. Nursten J. 1955 3081; M. Nilsson Acta Chem. Scand. 1958,12,537; R. G. R. Bacon and R. Bankhead,J. 1963,839. R. G. R. Bacon and H.A. 0. Hill J. 1964 1112. N. Kornblum Org. Reactions 1944 2 262; K. H. Saunders “Aromatic Diazo-Compounds,” Arnold and Co., London 1949. PROCEEDINGS the type ArN,+ -ArH effected e.g. by ethanol saturated and hydroaromatic molecules,” and from may be aided by copper or cuprous oxide. N3+-promoted transfer in alkoxide-carbonyl inter- These examples illustrate features of copper-actions of the Meerwein-Ponndorf type. New promoted hydrogen transfer which distinguish it examples of hydrogen transfer which proceed with- from palladium-promoted transfer between un-out catalysis have been incidentally observed. (Received Ocfober19th 1964.) L. M. Jackman in “Advances in Organic Chemistry. Methods and Results,,’ edited by R. A. Raphael et al. Vol.2, Interscience Publishers Inc. New York 1960. The Behaviour of The CN Radical in Active Nitrogen By I. M. CAMPBELL and B. A. THRUSH* EMISSION from the lower vibrational levels of the although this may be decreased slightly if CN reacts A2n state of CN (red system) and from the B2C+ significantly with NH during the titration time. state (violet system) particularly levels v’ = 0 and It has been suggested that reaction (3) yields the 5-7 occurs in active nitrogen containing traces of electronically excited CN.6 We find however that carbonaceous rnaterial.l* We have observed this the intensity of CN emission obeys the relation CN emission in studies of nitrogen-atom recombina- la [CN] “I2 [MI2 tion in a fast flow system when nitrogen containing and under our conditions the rate of CN violet traces of organic materials (particularly methane) is emission is only a factor of two less than that of passed through a radiofrequency discharge.In this reaction (2). Unlike the nitrogen afterglow the CN work nitrogen-atom concentrations were deter-emission does not extend to the walls of the flow mined by titration with NO and the recombination tube showing that a wall diffusion process competes followed by photoelectric measurements of the in- with radiation. Such competition produces a first- tensity of the nitrogen first positive emission which power dependence on pressure and reactions (2) and is proportional to the square of the nitrogen-atom (3) could only explain the observed emission kinetics concentration.ls3 The intensity of CN violet emission if NCN is removed predominantly and efficiently by was also proportional to the square of the concentra- diffusion to the wall.This is consistent neither with tion of nitrogen atoms in any experiment and there the high intensity of CN emission observed nor with was no evidence of any decrease in CN concentration the type of product excitation normally found in down the flow tube. The concentration of CN was transfer reaction^.^,^ typically about 5 x moles/c.c. This was deter- mined by titration with ammonia according to the We therefore prefer the mechanism reaction N + N + M = N* + M (4) CN + NH = HCN + NH2 (1) N*2+ CN = N2 + CN* (5) where kl is probably4 about 1013 ~m.~ mole-l sec.-l. N* + wall = N (6) Removal of CN by reaction with ammonia or with and identify N* as the metastable A3C$state which oxygen decreases the rate of nitrogen-atom removal.is formed to a considerable extent in nitrogen-atom Analysis of nitrogen atom decays by use of an re~ombination.~This state has sufficient energy I.B.M. 1620 computer showed that the acceleration (142 kcal./mole) to give the CN excitation energy due to CN which was postulated by Bayes? is of observed and it should readily transfer its energy to first order in [N] [CN] and total pressure; this CN which has an unpaired electron. must be attributed to the reactions These conclusions imply that A3Z$ N molecules N + CN + M = NCN + M (2) have a low steady state concentration in active nitro- N + NCN = N2 + CN (3) gen but this is consistent with the absence of their and a value of k = (5.6 f1.0) x 10l5 mole- Vegard-Kaplan band emission except at very high sec.-l at 20”c has been obtained for M = N, pressures.(Received Noveniber 2nd 1964.) * Department of Physical Chemistry University of Cambridge. R. A. Young and R. L. Sharpless J. Chem. Phys. 1963,39 1071. D. W. Setser and B. A. Thrush Nutiire 1963 200 864. J. Berkowitz W. Chupka and G. B. Kistiakowsky f. Chem. Phys. 1956 25 457. D. W. Setser and B. A. Thrush in course of publication. K. D. Bayes Cunud.J. Chem. 1961,39 1074. R. L. Brown and H. P. Broida J. Chem. Phys. 1964,41,2053. F. J. Lipscomb R. G. W. Norrish and B. A. Thrush Proc. Roy. Suc. 1956 A 233 455. J. C. Polanyi J.Quunt. Spec. and Rad. Trans. 1963,3 471. J. F. Noxon J. Chem. Phys. 1962,36,926. DECEMBER 1964 411 Transient Spectra of Some Inorganic Radical Anions Produced by Reactions of the Hydroxyl Radical By G. E. ADAMS,J. W. BOAG,and B. D. MICHAEL* IT has been shown that the hydroxyl radical pro- duced during the pulsed radiolysis of aqueous solu-tions reacts rapidly with many inorganic reducing i0ns.l In particular relative and absolute rate data have been obtained from competition studies using the transient absorption spectra produced in some of these a d b e C f that produced in iodide ion solution. The maximum at 3900 A presumably due to 12- decays within a few microseconds to a permanent absorption which is identical to that of the ion 1,.We conclude that these spectra are probably due to radical anions produced by electron transfer from the ion to OH since (a) they are not suppressed bv oxygen; (b) the 9 h Wavelength Xl3OA Transient spectra produced in irradiated neutral solutions of some reducing anions (a) Silicate (b) Carbonate (c) Arsenite (dl) Sulphite (d2) Bisulphite (e) Selenite (f) Tellurite (8)Thiosulpliate (h) Thiocyanate (i) Zodide. Using the technique of pulsed absorption spectro- graphy we have observed several new transient spectra produced after a 0.2 or 2.0 microsecond pulse of 2 Mev electrons had been delivered to aqueous solutions of various reducing anions of groups 4,5 6 and 7 of the Periodic Table. The were de-aerated and then saturated with nitrous oxide before irradiation.Fig. 1 shows several transient spectra produced in irradiated solutions of Some simple reducing anions Of groups* The strong absorption maximum produced in tions containing silicate ion is strongly reminiscent of that of its analogue the carbonate ion. These transient spectra decay rapidly particularly peak intensities are enhanced when oxygen is re- placed by nitrous oxide which increases the net yield of OH radicals by the reaction4 N20 f eaq-N f 0-; (c) they are suppressed by a suitable concentration of carbonate ion itself an efficient OH scavenger; and (d)the rate constants for the reactions obtained either by direct observation of the build-up of the absorption using an oscillographic technique or by competition methods appear to increase with the standard potentials for the general reaction An-+ OH -+ OH-.(Received September 3rd 1964.) * Research Unit in Radiobiology British Empire Cancer Campaign Mount Vernon Hospital Northwood Middlesex. J. W. Boag and G. E. Adams XVZZI Annual Symp. Cellular Radiation Blol. Houston March 1964 in press. G. E. Adams and J. W. Boag Proc. Chem. Soc. 1964 112. G. E. Adams J. W. Boag and B. D. Michael to be published. * F. S. Dainton and D. B. Peterson Proc. Roy. SOC.,1962 A 267,443. PROCEEDINGS Optical Rotatory Dispersion of Lactones By J. P. JENNINGS W. KLYNE,and P. M. SCOPES* THEdevelopment of an automatic recording spectro- polarimeter,' with a range down to about 210 mp has enabled us to examine the optical rotatory dis- persion (ORD) curves of carboxylic compounds in their region of weak absorption at 215 mp.Acids esters lactones and amides (including peptides) have Cotton effects with a first extremum at about 225 mp but no theoretical interpretation of the results com- parable with the Octant rule for ketones has been advanced. Okuda er d4have recently discussed the ORD curves of some carbohydrate lactones. We have now measured the ORD curves of a large number of polycyclic lactones ;these compounds are particularly favourable for stereochemical study because the chromophore is held in a fixed con- formation. The lactones show regular patterns of behaviour comparable with those shown by ketones e.g.3-0x0-4-oxa-5 a-steroids (1) and 17-0x0- 17a- oxa-D-homosteroids (IT) show positive and negative Cotton effects respectively. R 0&& H 0Q4 - i !! I + I + ! - ! These facts can be interpreted by a lactone sector rule; in this treatment the molecule is viewed in the plane of the lactone group along the bisectrix of the O-C-0 angle i.e. the line of the carboxyl carbon and its attached carbon atom (111). (The lactone group is considered as roughly planar; cf. X-ray *Westfield College N.W.3. ~tudies.~) The space around the lactone group can be divided into sectors by means of planes meeting at the carboxyl carbon atom and from the empirical data it can be shown that the signs used in the ketone octant rule3 must be reversed for the lactone sector rule.Thus atoms lying in the back upper right and lower left sectors make positive contributions to the lactone Cotton effect while atoms in the back upper left and lower right sectors make negative contribu- tions (IV). A semiquantitative treatment has been suggested to us by Professor A. Moscowitz (University of Minnesota) to whom we are greatly indebted for his interest and help. Both carbon-oxygen bonds are regarded as having some double-bond character and as a rough approximation the two bonds are con- sidered to be identical. Each bond in turn is treated as a double bond and the signs of the contributions made by the atoms (alkyl groups) in different octants are all determined according to the ketone.octant rule3 (Va and Vb). (In Va Vb and VI the group is seen from above in projection on the plane of the lactone group. The signs given are those of the back upper octants i.e. those above the plane of the lactone group.) The two diagrams (Va and Vb) are then superimposed giving (VI) the signs of the contribu- tions of atoms in some sectors cancel in varying degrees (Sectors A C D F) and in others reinforce one another giving on balance a positive rotation in the back upper right sector (E) and a negative con- tribution in the back upper left sector (B) (VI) in accordance with empirical observations. It is necessary to consider two views of each molecule in order to predict the sign of its Cotton eiTect from the lactone sector rule.These are (a) the view along the bisectrix of the 0-C-0 angle (the usual octant projections; Ia and Ila) and (b) thc view of the molecule from above projected on to the plane of the lactone ring (the new sector projections; lb and IIb). Projections for the 3-0x0-4-oxa-5 a-steroid (I) are shown in (la) and (Ib). When the molecule is viewed along the bisectrix of the 0-C-0 angle it lies en- tirely in the back upper right sector (la); projection (Ib) shows that atoms 9 10 11 12. 13 17 lie in the region of high positive contribution. This is in keep- ing with the experimental results; 17P-hydroxy-E. J. Gilham and R. J. King J. Sci. Instr. 1961 38 21; J. P. Jennings Biochem. J. 1963 86 16~. I. P.Dirx and F. L. J. Sixma Rec. Trav. chim. 1964,83,522; W. Gaffield Chem.and Ind. 1964,1460; J. P. Jennings W. Klyne and P. M. Scopes J. Chem. SOC.,in press. W. Moffitt A. Moscowitz R. B. Woodward W. Klyne and C. Djerassi J. Amer. Chem. SOC.,1961 83,4013. T. Okuda S. Marigaya and A. Kiyomoto Chem. Phurm. Bull. Japan 1964 12 504. A. McL. Mathieson Tetrahedron Letters 1963 2 81 and other references therein. DECEMBER 1964 3-oxo-4-oxa-5a-androstanehas [+I +6250 at 226 mp. For the 17-oxo-17a-oxa-~-homosteroids a negative Cotton effect would be predicted by the sector rule (Ira and Ilb) ;in fact 3p-acetoxy- I 7-0x0-17a-oxa-~-homo-5a-androstane has [+] -5150 at 217 mp. I ! I -.-----bsitive contribution -! ! Me i Lactones can be considered as heterocyclic analogues of decalones hexahydroindanones and bicyclo [3,3,0]octanones (cf.treatment of deca-W. KIyne Experientia 1964 20 349. lone@); each series exists in cis-and trans-forms and with the heteroatoms in positions 1 or 2 relative to the bridgcheads this gives twelve main stereochem- ical types of which nine have already been examined. We have measured the ORD curves of over seventy lactones of these nine main types and the sector rule 1 .... iijijii Negative contribution .... I offers a satisfactory explanation of the observed sign of the Cotton effect in 95 % of the compounds. (Received November 2nd 1964.) PROCEEDINGS 1-and 2-Lithiobiphenylene and Derived Compounds By WILSON BAKER,A.J. BOULTON R. HARRISON, CHARLES and J. F. W. MCOMIE" THEstudy of 1-substituted biphenylenes has been greatly hindered by their inaccessibility. The usual synthesis of biphenylenes involves the reaction of substituted 2,2'-di-iodobiphenyls with cuprous oxide at 350-380" and the iodinated biphenyls required for the preparation of 1 -substituted biphenylenes are generally less accessible and give lower yields than those needed for 2-substituted biphenylenes.lY2 Moreover 1-substituted biphenylenes cannot nor-mally be prepared by electrophilic substitution of bi~henylene.~,~ We now report the preparation of 1- and 2-lithiobiphenylene and their conversion into other 1- and 2-substituted biphenylenes. A solution containing 1 -1ithiobiphenylene and a little 2-lithiobiphenylene was obtained when bi-phenylene and an excess of n-butyl-lithium in ether was kept for 4 days.Treatment of this solution with solid carbon dioxide followed by esterification of the resulting acids with diazomethane gave 1-methoxy- carbonyl- (49 %) m.p. 81 ",and 2-methoxycarbonyl- biphenylene (2.5 %) m.p. 114-1 15" together with 1-pentanoylbiphenylene (9.5 %) m.p. 63" and a trace of the 2-pentanoyl isomer. When the lithiobi- phenylene solution was treated with acetyl chloride it did not give the 1-acetyl compound but this com- pound (m.p. 58.5") was made from the 1-carboxylic acid via the acid chloride and diethyl ethoxymag- nesi~malonate.~ 1 Lithiobiphenylene reacted with oxygen to give 1-hydroxybiphenylene (18 %) m.p.132" and with NN-dimethylformamide to give biphenylene-1 -aldehyde characterised as its 2,4-di- nitrophenylhydrazone m.p. 287" (decomp.). 2-Lithiobiphenylene prepared by the interaction of 2-bromobiphenylene and n-butyl-lithium can be used similarly for the preparation of 2-substituted biphenylenes. Treatment of 1-and 2-lithiobiphenyl- ene with cyclohexanone followed by dehydration and dehydrogenation gave 1-phenyl- (m.p. 46.5") and 2-phenyl-biphenylene (m.p. 125.5 O) respectively. (Received October Dth 1964.) * Department of Organic Chemistry The University Bristol. W. Baker J. W. Barton and J. F. W. McOmie J. 1958 2658. J. W. Barton et al. unpublished results. W. Baker J. W. Barton and J. F.W. McOmie J. 1958 2666. A. Streitwieser and I. Schwager,J. Amev. Chem. SOC.,1963 85 2855. H. G. Walker and C. R. Hauser J. Amer. Chem. SOC.,1946 68 1386. The Crystal Structure of Di-p-tolylmercury By N. R. KUNCHUR and M. MATHEW* THERE is a considerable interest in the structures of compounds HgX2 or HgXY in which one or both bonds are to be carbon or sulphur. The Hg-C bonds are nonlinear in Hg(CN)z as shown by a combined X-ray and neutron diffraction w0rk.l Diphenyl-mercury has a high dipole moment and this has been attributed to the bending of the molecules.2 How- ever the X-ray structure analysis of Ziolkowska3 shows the molecule to be planar with C-Hg-C linear. This analysis was based on the projections and the lack of detail in the report makes any assess- ment of its accuracy difficult.We have now solved the structure of di-p-tolyl- mercury Hg(CGH,CH3) which crystallises in the monoclinic system with a = 10.13 (&-0.03) b = 5.09 (& 0.02) c = 11.72 (& 043) A fi = 92" and 2 = 2. Since the space group is P 2,/c the mercury atom must lie at a centre of symmetry and the C-Hg-C angle must be 180". This has been con- firmed by a three-dimensional analysis based on 635 independent reflexion (Cu-K radiation). When only the mercury atom was included the R-value was 0.157. When the carbon atoms were also included (in positions first found from a mercury-phased electron-density synthesis and then refined by a difference synthesis) R fell to 0-12 for the observed reflexion.The molecule is planar; and there are no intermolecular Hg-.C contacts which might cor-respond to bonds. The high dipole moment in diphenylmercury must therefore be due either to atom polarisation (or to solvation). (Received September 22nd 1964.) * Chemistry Department University of Western Ontario London Ontario Canada 1 J. Hvoself Acta Chem. Scand. 1958 12 1658. A. F. Wells "Structural Inorganic Chemistry," Oxford Univ. Press 1962 p. 892. a Blanka and Ziolkowska Roczniki Chern. 1962 36 1341. DECEMBER 1964 415 Complex Formation in Dimethyl Sulphoxide By R. E. DODD and R. P. H. GASSER* DIMETHYL SULPHOXIDE (DMSO) is a good solvent for many ionic compounds. We have investigated qualitatively and quantitatively the solution of some metal cyanides.Those of sodium potassium copper(I) nickel zinc and cobalt are insoluble and those of mercury(I1) and cadmium are soluble. How- ever mixtures of potassium cyanide with copper(I) nickel zinc or cobalt cyanides do dissolve pre- sumably with the formation of a complex salt. The solution of mercury(u) cyanide dissolves potassium cyanide though that of cadmium cyanide does not. The heats of solution of mixtures of potassium cyanide with either silver($ cyanide or copper(1) cyanide were measured with a conventional twin calorimeter in a "dry-box". For silver(1) cyanide the ,-reaction AgCNsolid KCNsolid 4 KCN,AgCN,,m AH = -8-5 kcal./mole AgCN occurred. For copper(1) cyanide one of two reactions occurred depending on whether the copper or the potassium cyanide was in excess.These were CUCNf3olid + KCNexcess solid -+ 3 KCN,CUCN AH = -25.3 kcal./mole CuCN CuCNexcess solid f KCNsolid +KCN,CuCN AH = -15.3 kcal./mole CuCN The stoicheiometries of these reactions thus exactly parallel those observed in water and pre- sumably the complex ions Ag(CN), Cu(CN),- and CU(CN),~- are formed. (Received October 26th 1964.) * Physical Chemistry Laboratory South Parks Road Oxford. Thermal Rearrangement of Methyl cis-2-Alkylcyclopropanecarboxylates E. MCGREER W. K. CHILT S. MCDANIEL* By DONALD NORMAN and ROBERT WEhave recently prepared a number of dialkylcyclo- There is one literature example which may be propane derivatives of structure (I).In attempts to analogous to our reaction. Von Auwers and purify these compounds by vapour chromatography at temperatures above 210" rearrangement took place to give 78-unsaturated esters. For example methyl 2,2-dimethyl- 1 -cyanocyclopropanecarboxyl-ate (Ia) gave methyl 2-cyano-4-methylpent-4-enoate (11) and methyl 2,2-diethyl-l-cyanocyclopropane carboxylate (Ib) gave a mixture of methyl cis- and trans-2-cyano-4-ethyIhex-4-enoate. At temperatures below 160" vapour Chromatography gave pure (Ia). The fact that the rearrangement product was exclusively the y8-isomer suggested to us that a molecular rearrangement was involved. To check this possibility we have heated methyl cis- and trans- 1,2-dimethylcyclopropanecarboxylateat 300" for 18 hours in a sealed tube.The cis-isomer remained un- changed. The trans-isomer (111) rearranged com-pletely to methyl 2-methylpent-4-enoate (V). The mechanism for this rearrangement is probably analogous to that reported recently by Ellis and Freyl for the isomerisation of cis-1-methyl-2-vinylcyclo-propane and would involve the enol (IV) as an inter- mediate. The fact that the trans-isomer (111) reacts in conditions under which the cis-isomer is stable confirms the previous assignment of structure to these isomers by Van Auken and RineharL2 Ungemach3 found that the polymeric anhydride of trans -1,2 -dimethylcyclopropane-1,2-dicarboxylic acid when heated yielded the anhydride of y-methyl- a-methyleneglutaric acid. Me '$= CH2 H2< (1) a; R= Me b;R= Et CH(CN)CO,Me OMe (IV) b4 The reaction described herein will be valuable for structure determination in the cyclopropane field.It also provides a convenient synthetical route to y8-unsaturated esters. The reaction also suggests by analogy that molecular hydrogen transfer may be important in the isomerisation of cis-ap to Pa-un- saturated esters. (Received September 21st 1964.) * Department of Chemistry The University of British Columbia Vancouver 8 B.C. Canada. R. J. Ellis and H. M. Frey Proc. Chem. Soc. 1964,221. T. V. Van Auken and K. L. Rinehart,jvn.,J. Amer. Chem. Soc. 1962,84,3736. K. von Auwers and 0. Ungemach Annalen 1934 511 152. PROCEEDINGS The Grignard Addition to Cyclic Ketals By R.A. MALLORY and 1. SCHEER* S. ROVINSKI CYCLIC ketals or dioxolans are generally regarded as being stable under alkaline conditions. Ketalisation of a carbonyl function is used as a protective device. Other reactive groups on a molecule may be altered under non-acidic conditions while a desired keto- group is protected via the ketal and subsequently regenerated by acid hydrolysis. However it has now been found that ketals may not always be stable in the presence of strongly basic reagents. We have added Grignard reagents to cyclic ketals to produce appropriately substituted glycol monoethers of tertiary alcohols. Thus cyclohexanone ethylene ketal and two molecular equivalents of methylmagnesium bromide when heated in benzene at 75" for 16 hours gave 2-( 1-methylcyclohexyloxy)ethanol in 91 % yield.Grignard reagents such as n-butylmagnesium bro- mide and phenylmagnesium bromide reacted with the ketal to form 2-( 1-n-butylcyclohexyloxy)ethanol and 2-( 1-phenylcyclohexyloxy)ethanol,respectively. This reaction is not limited to ethylene ketals and appears to be applicable to cyclic ketals in general. Methylmagnesium bromide was added to the tri- methylene ketal the 1,Zpropene ketal and the 1,3-butene ketal of cyclohexanone to give 3-(1- methylcyclohexyloxy)propanol 2-( 1-methylcyclo-hexyloxy)propanol and 3-( 1-methylcyclohexyloxy)- butanol respectively. In similar fashion we have prepared glycol mono- ethers of tertiary alcohols from ketals of such typical ketones as cyclopentaiione butan-2-one tridecan- 2-one acetophenone benzophenone fluoren-Pone cholestanone pregnenolone and 3P-hydroxy-androst-4-en- 17-one.Blomberg Vreugdenhil and Homsmal have recently reported on the preparation of Grignard reagents from 2-monoalkyl substituted 1,3-dioxolans with subsequent hydrolysis to ring-opened glycol monoethers of secondary alcohols. In the course of our work we found that Grignard reagents react with various cyclic acetals to yield glycol monoethers. As one example benzaldehyde ethylene acetal reacted with methylmagnesium bromide to afford 2-(1-methylbenzy1oxy)e thanol. All compounds reported gave satisfactory analyt- ical data. The scope of the above described reaction is under investigation.(Received,September 14th 1964.) * Division of Organic Chemistry Ortho Research Foundation Raritan N.J. U.S.A. C. Blumberg A. D. Vreugdenhil and T. Homsma Rec. Trav. chim.,1963 82 355. Trifluoromethoxides of Alkali Metals By D. C. BRADLEY and C. J. WILLIS* M. E. REDWOOD TRTFLUOROMETHANOL, CF,.OH is unknown and is generally assumed to be incapable of existence because of the ease with which hydrogen fluoride would be eliminated. Because of this no metallic trifluoromethoxide has hitherto been described. We now report the preparation of stable crystalline tri- fluoromethoxides of the heavier alkali metals i.e. MOCF, where M = K Rb or Cs. We formulate these as ionic compounds containing the trifluoro- methoxide ion [OCF,]-.The negative charge in this ion would formally rest on the oxygen atom but the greater electronegativity of fluorine would clearly lead to a more even distribution of charge over the ion enhancing its stability. The trifluoromethoxide ion is isoelectronic with the fluoroborate ion and the X-ray powder patterns of the corresponding salts are very simiiar. Detailed indexing has been carried out for rubidium trifluoro- methoxide showing it to be isomorphous with rubidium fluoroborate. The crystals are ortho-rhombic the cell dimensions being a b RbBF 9-07A 560A RbOCF 8.86 5.79 c Volume 7-23 A 367 A3 7.37 378 It is unlikely that such a similarity in crystal structure would be fortuitously shown by any com- pounds that were not composed of isostructural ions.The trifluoromethoxides of potassium rubidium and caesium were prepared by the action of carbonyl fluoride on a suspension of the metal fluoride in acetonitrile contained in a sealed tube under rigorously anhydrous conditions. F-4-COF + [OCF,]-Visible reaction occurred immediately at room temperature and subsequent removal of solvent and excess of carbonyl fluoride left a crystalline solid stable indefinitely at 20" in vacuu which was shown by analysis and by che stoicheiometry of reaction to be fornied by the combination of carbonyl fluoride with the metal fluoride in a 1:l molar ratio. No Department of Chemistry University of Western Ontario London Canada. J. L. Hoard and V. Blair J. Amer. Chem.Soc. 1935 57 1985. DECEMBER 1964 reaction was detected under similar conditions between carbonyl fluoride and lithium sodium barium or thallium(1) fluorides. The above reaction is reversible and on heating to 80-100" in vucuo the trifluoromethoxides decomposed to regenerate car- bony1 fluoride leaving the metallic fluoride. From the rates of decomposition the thermal stabilities were shown to decrease in the order Cs > Rb > K. The trifluoromethoxides described here are the first examples of fully fluorinated alkoxides to be reported. It is now apparent that many of these will be highly ionic in nature and preparative methods for other such compounds are being sought. (Received October 12th 1964.) The 1,2,4,5-Tetramethylthiobenzene Cation-radical By ARNOLD ZWEIGand WILLIAM G.HODGSON* OFthe many salts of cation-radicals of substituted benzenes that have been reported only Wurster's blue salts (derived from NNN'N'-tetramethyl-p-phenyIenediamine)lv2 and triarylaminium salts3 are reported to be stable both as solid and in solu- tion. We report the properties of another stable substituted benzene cation-radical that derived from 1,2,4,5-tetramethyIthioben~ene.~ This compound underwent one-electron oxidation electrochemically in acetonitrile (El oxidn. = 1-08v against S.C.E.). The cation radical could also be generated by dissolution of the tetramethylthio- benzene in concentrated sulphuric acid or formed as an insoluble salt with antimony pentachloride.The e.s.r. spectrum of the cation-radical in acetonitrile showed the expected triplets with correct intensity for an interaction with twelve equivalent protons. There was severe asymmetry of the spectrum in sulphuric acid; nevertheless an odd number of triplets was readily discernible. In deuterosulphuric acid the triplet splitting disappeared within 48 hr. The coupling constants are u(H) = 0.71 gauss a(SCH,) = 2-57 gauss g = 2.0075 in acetonitrile and sulphuric acid. The deep blue sulphuric acid solution had absorption maxima at 728 585 and 388 mp. Only the 585 mp band remained constant in intensity for 48 hours. A fine blue po~der,~ m.p. 142-143" (decomp.) was obtained in 85% yield on mixing the tetra- methylthiobenzene with an equimolar amount of antimony pentachloride in chloroform.The e.s.r. spectrum of this material showed an asymmetric signal of a species with an anisotropic g tensor with axial symmetry and with g,,= 2.0027 and gl = 2.0106. The uncorrected molar magnetic suscepti- bility at 25" (Gouy balance) was 940 x c.g.s. units leading to an estimated corrected molar susceptibility of 1327 x c.g.s. units (theory for one unpaired electron 1250 x c.g.s. units). The i.r. spectrum of the antimony complex was almost identical with that of the tetramethylthiobenzene except for slight shifts (e.g.,single aryl H at 838 cm.-l instead of at 845 cm.-l) and a new band at 340 cm.-l which can be ascribed to the antimony-chlorine bond. Thus this substance is not an SbCl complex of a halogenotetramethylthiobenzene.s A pressed pellet of the antimony pentachloride complex of the tetramethylthiobenzene had a resisti-vity of 9 x ohm cm.With bromine the tetra- methylthiobenzene formed a diamagnetic red-brown 1:1 adduct m.p. 132-134",5 which regenerated the starting material on treatment with 10% aqueous sodium hydroxide. Hiickel molecular orbital calculations for the tetramethylthiobenzene with as = ac + 1.0& and PCS = 0.4 Pcc,' suggest an unpaired electron density of 0.125 on each sulphur and each contiguous ring position and no unpaired electron on the 3 and 6 positions of the ring. For 1,4-dimethylthiobenzene,8 the unpaired electron density on sulphur is 0.2415 and a(SCH,) is 5.33 gauss. The ratios of unpaired electron densities on sulphur and the S-methyl proton coupling constants in the two cation radicals indicates that Q(SCH,) = 21 gausslelectron if the suggested sulphur parameters are employed.The McLachlan self-consistent field treatmentQ employing the Hiickel starting wavefunction and = 1.2 gave a spin density of -OW64 for the 3 and 6 positions and 0.1467 and 0.1264 for the other ring positions and sulphur respectively. The ring proton * American Cyanamid Company Chemical and Research Service Departments Stamford Connecticut U.S.A. L. Michaelis M. P. Schubert and S. Granick J. Amer. Chem. SOC.,1939,61,1981. a L. Michaelis and S. Granick J. Amer. Chem. SOC.,1943,65 1747. R.1. Walter J. Amer. Chem. SOC.,1955,77 5999.The neutral compound has been reported by J. Pollack Monatsh. 1914,35 1445 but a more convenient synthesis involves the reaction of 1,2,4,5-tetrabromobenzenewith cuprous methyl sulphide. Analysis satisfactory for a 1 :1 adduct. H. H. Perkampus and E. Baumgarten 2.phvs. Chem. (Frankfirrt) 1963 39 1. 'The choice of these parameters will be fully discussed in a forthcoming paper. A. Zweig W. G. Hodgson W. H. Jura and D. L. Maricle Tetrahedron Letters 1963 1821. A.D. McLachlan Mol. Phys. 1960,3,233. PROCEEDINGS coupling constant for 1,2,4,5-tetrarnethoxybenzene meters thus correctly predicts a smaller nodal nega- was found to be 0.89 gauss,1° and the McLachlan tive spin density for the cation of 1,2,4,5-tetra-method with the parameters employed suggested a methylthiobzenene.spin density of -0.0675.10 The method and para- (Received October 29th 1964.) lo A. Zweig W. G. Hodgson and W. H. Jura J. Amer. Chem. SOC.,1964 86 4124. Free Radicals in Pyrolytic Carbon from Allyl Bromide By K. A. HOLBROOK* IT has been common practice in many homogeneous gas kinetic studies to attempt to minimise surface catalysis by coating the reaction vessel with a car-bonaceous fi1m.l Such films are produced by the pyrolysis of olefins or halogenated hydrocarbons usually at temperatures around 400-500"~. Recently it has been suggested that in some respects these films might be more active than a clean glass surface2 and Holbrook and Rooney3 found evidence that films from pyrolysis of ethyl chloride behaved differently towards olefin isomerisation from those produced by the pyrolysis of cis-but-2-ene or allyl bromide.Evidence has now been obtained from some e.s.r. measurements that a high concentration of free radicals exists in the heavy carbon deposit produced from allyl bromide whereas none could be detected in cis-but-2-ene or ethyl chloride deposits. These carbon films were produced in 4-mm. silica sample tubes packed with silica-glass fibres under the condi- tions shown in the Table and sealed under vacuum. An estimate of the free radical concentration was made by comparing the area under the first derivative absorption curve with those for standard concentra- tions of diphenylpicrylhydrazyl. Source cis-But-2-ene Pressure 150 (mm.) Temp.410-460 ("d Ethyl chloride Allyl bromide 150 125 470-500 380-390 The e.s.r. spectrometer used was a Hilger & Watts Microspin instrument operating at 9400 Mc./sec. with 100 Kc./sec. modulation with the sample at room temperature. The estimate of spin concentra- tion is approximate largely due to errors in the double integration involved and in estimating the weight of material deposited but is considered to be within a factor of ten. This figure is similar to the unpaired spin concentrations previously observed in charred sugars cellulose and other organic materials at low temperatures," where it is postulated that these are formed by broken-edge bonds which pro- duce resonance-stabilised unpaired electrons. The signals were considerably reduced on admitting air to the samples presumably because of quenching by paramagnetic oxygen.It has already been suggested by Cullis5 that pyrolytic carbon might differ depending upon the nature of the source of material and evidence has also been presented to show that halogen substitu- tion can markedly alter the structure of pyrolytic carbon deposits.6 It is therefore reasonable to postu- late that carbon from allyl bromide probably derived via processes involving allyl radicals is more likely to have an unsaturated character capable of stabilising free electrons than is carbon produced from ethyl chloride possibly via the polymerisation of ethylene. The immediate implications for gas kinetics are obvious. Carbon surfaces derived from allyl bro- mide must be considered carefully before they are assumed to be inert.In the pyrolysis of 2-chloro- Time of coating Result (hr.) 67-0 No detectable signal 47.5 No detectable signal 47.5 -lOl8 spins/g. butane the close agreement of the rates of the elimination reaction in allyl bromide coated,' ethyl chloride ~oated,~ and KC1-treated vessels8 probably indicates now more clearly than before that this is a homogeneous process despite the differences dis- played by these surfaces towards olefin isomerisation. (Received November 6th 1964.) * Denartment of Chemistry. The University. Hull. DaGiels and Veltman J.-Chem. Phys. 1939 7 756; Brearley Kistiakowsky and Stauffer J. Amer. Chem. SOC., 1936,58,43; Barton and Howlett J.1949 155; Agius and Maccoll J. 1955 973. a Laidler and Wojciechowski Trans. Faraday SOC., 1963 59 369. Holbrook and Rooney J. in the press. * Bennett Ingram and Topley J. Chem. Phys. 1955 23,215; Singer Proc. 5th Conference on Carbon Pergamon 1963 Vol. 2 p. 37. ti Cullis Fuel. SOC.J. 1963 14 7. Cullis Manton Thomas and Wilman Acta Cryst. 1959 12,382. Maccoll and Stone J. 1961 2756. Heydtmann and Rinck 2.phys. Chem. (Frankfurt),1961,30,250; 1963,36,75. DECEMBER 1964 419 Fucoxanthin By R. BONNETT, A. A. SPARK,J. L. TEE,and B. C. L. WEEDON* RECENT on fucoxanthin the charac- publication~l-~ teristic carotenoid of brown algae and diatoms prompt us to summarise our own findings. Mass spectrometry established the molecular formula as C42H5 806, and indicated two hydroxyl groups and one acetoxy-group.O-Acetyl group analysis (alkaline hydrolysis) gave a value of 1.0 (cf. ref. 3). Fucoxanthin yielded a monoacetate m.p. 147-148”(an amorphous form m.p. 118-1 19”,probably identical with Jensen’s derivative,l was also ob-and the mixture of “allenic aldehydes” gave aa-di- methylsuccinic acid;? the former also gave dimethyl- malonic acid.? served) and a moncchloroacetate m.p. 153-1 54”. Both esters contained a (tertiary) hydroxyl group; treatment of the acetate with phosphorus oxychloride gave an “anhydroacetate,” m.p. 139-140” (no i.r. bands due to OH) with visible-light absorption properties siniilar to those of fucoxanthin. Reduction of fucoxanthin with lithium aluminium hydride gave a mixture of “fucoxanthols” with the light-absorption properties of a conjugated octaene (cf.ref. 2). Catalytic reduction gave “perhydro- fucoxanthin” which was optically active (cf. con- flicting reports for fucoxanthin4-‘j). The perhydro- compound yielded acetic acid? on alkaline or acidic hydrolysis but was not attacked by periodic acid. Permanganate oxidation of fucoxanthin gave di- methylmalonict and a a-dimethylsuccinic acid? (cf. ref. 7). Partial oxidation with zinc permanganate gave a tetraenedial regarded as (I) (expected shift in Amax. on condensation with acetone) the known* pentaenedial (11) a pentaenealdehyde C25H3404 m.p. 195-196” T 0.55 and a hexaenealdehyde C27H3604 m.p. 203-204” T 0-45 (doublet J = 7-5 c./sec.) (formulaz by mass spectrometry polyene chromophores from Amax.of the hydride reduction products) and a mixture of “allenic aldehydes” which (like fucoxanthin its esters the anhydro- acetate and the fucoxanthols) exhibited i.r. absorp- tion in the region normally associated with allenes. Further oxidation of the C25- and C,,-aldehydes gave the dialdehydes (1) and (11) respectively (identified by U.V. spectra and mixed chromato- grams). Complete oxidation of both the C,,-aldehyde HO The C,,-aldehyde formed a monoacetate m.p. 162-163” (no i.r. band due to OH) and reacted with the geranyl Wittig reagents to give a conjugated octaenone (Amax. before and after hydride reduction). The aldehyde’s n.m.r. spectrum (at 60 and 100 Mc./sec.) had many features in common with that of fucoxanthin including an AE3 system (7 6.32 and 7-40; J = 18 c./sec.) ascribable9 to a methylene group adjacent to a carbonyl function.The C2,- aldehyde is formulated as (111) and the C25-com- pound as its lower vinylogue. Structure (IV) is advanced as a working hypothesis for fucoxanthin. The authors are indebted to Mr. A. McCormick for mass-spectral data Mr. J. H. Beynon for the n.m.r. results at 100 Mc./sec. and to Drs. G. B. Pickering (Tropical Products Institute) M. S. Barber J. B. Davis H. Yokoyama and A. K. Mallams for their help with some of the work. One of them (J.L.T.) thanks the Institute of Seaweed Research and another (A.A.S.) D.S.I.R. for a maintenance grant.(Received November 6th 1964.) * Department of Chemistry Queen Mary College Mile End Road London E.1. t Identified by mixed gas-liquid chromatogram of the acid or its methyl ester with an authentic specimen. A. Jensen Acta Chem. Scand. 1961 15 1604. a A. Jensen Actu Chem. Scand. 1961 15 1605. A. Jensen Actu Chem. Scand. 1964 18,840. ‘P. Karrer A. Helfenstein H. Wehrli B. Pieper and R. Morf Helv. Chim. Actu 1931 14 623. I. M. Heilbron and R. F. Phipers Biochem. J. 1935 29 1369. Dr. N. J. Antia confirms optical activity (private communication). ’F. G. Torto and B. C. L. Weedon Chern. and Ind. 1955 1219. 0. Isler H. Gutmann H. Lindlar M. Montavon R. Ruegg G. Ryser and P. Zeller Helv. Chim. Acta. 1956,39,463. T. Takahashi Tetrahedron Letters 1964 No.11 565. PROCEEDINGS The Orientation of Free-radical Addition to Olefins By J. M. TEDDER and J. C. WALTON* ACCORDING to the present generally accepted view1 the orientation of the addition of free radicals to unsymmetric olefins is governed by the relative stabilities of the two possible addend radicals formed in the initial step (e.g.,A or B). RY R. + XCH=CH2 --t XCH-CH2R -+ (A) 2 XY CH-CH2R (0 RY R.+ XCH=CH2 --t RXCH-CH -4 1 (B) RXCH-CHZY (D) These conclusions are based on experiments from which only one product (i.e. either C or D) has been isolated and indeed the reports of experiments in which both isomers have been isolated are few. If the above view is correct then for reactions which do give both isomers changes in X should only have a small effect on the rate of formation of B but a pronounced effect on the rate of formation of A.In order to test this theory it is necessary to find a system in which a single radical will add to both ends of a number of unsymmetrical olefins. It is the pur- pose of the present Communication to report the preliminary results of such a study. Rather than simply measure rates the reactions have been carried out in the gas phase over a wide temperature range and the Arrhenius parameters for the rate of attack by trichloromethyl radicals at each end of four different olefins have been determined. Full experi-mental details will be reported later but the experi- mental technique used has already been described fully? Within experimental error log Al is constant for all the additions except for tetrafluoroethylene and the rates are therefore determined by the activation energies.These results show quite clearly that for trichloromethyl radicals at least the rate of addition is determined principally by substituents on the carbon atom attacked and only to a lesser extent by the substituents attached to the carbon atom at which the unpaired electron is sited i.e. the exact reverse of the above prediction. We therefore suggest that the orientation of radical addition is determined principally by the relative strengths of the two possible bonds initiallv jormed. This must in general lead to exactly the same prediction of orientation as argu- ments about the stabilities of the products.At present assessing the relative strengths of the bonds formed is as difficult as estimating the relative stabi- lities of A and B and can only be done in a very qualitative manner. The important conclusion is that the reaction is controlled by the location of the new bond rather than by the location of the unpaired electron. Although we believe this criterion involving bond strength will prove generally applicable we do not mean that other factors such as polar and steric effects are not important in some cases but a great deal of further work involving different radicals as well as different olefins will be necessary to assess their importance. Finally the very fact that the rela- tive rates of attack at the two possible sites in an unsymmetric olefin vary with temperature makes a bridged type transition state rather improbable.(Received October 5th 1964.) The addition of trichloromethyl radicals to olefins in the gas phase (log A in [.mole-l sec-l; E in kcal./mole) Addition logA1 El Addition log A El Addition log Al El to CH2 to CHF to CF H,C=CH2 5.6 3.2k0.3 H,C=CHF 5.4 -5.3h0.2 H,C=CF 5.5 8.3f0.5 FHC=CH2 5.5 3.3+0.2 F2C=CF2 7-1 6.1f0-4 F2C=CH2 5.6 4.6k0.3 ---I * Department of Chemistry Queen’s College Dundee. See for example J. D. Roberts and M. C. Caserio “Basic Principles of Organic Chemistry,” W. A. Benjamin Inc. New York 1964 p. 189. T. J. Dougherty J. Arnev. Chern. SOC.,1964 86,460.3 J. M. Tedder and J. C. Walton Trans. Furday SOC.,1964,60 1769. Rearrangement of the s-Triazolo[4,3-a]pyridine System By K. T. POTTSand H. R. BURTON* WEhave found that the s-triazolo [4,3-a]pyridine base. Rearrangement occurs under reflux during system (1; R = H Me Ph NH,) undergoes re-several hours and the isomeric system is formed in arrangement to the isomeric s-triazolor 1.5-alpyridine good yield. An intermediate of type (111) was most system (IT; R = H Me Ph NHd in the presence of likely involved and accounts for the characteristic DECEMRER 1964 transient red colour of the reaction mixture. The structures of the rearranged products were estab- lished by analytical and spectral data,l by com-parison with specimens prepared by unambiguous methods or by the following series of transforma-tions 421 s-Triazolo [4,3-a]pyridin-3-01 and the 3-thiol did not undergo rearrangement to the corresponding isomers.They were stable in acid solution as were the other members of the [4,3-a] series investigated and in base underwent decomposition to 2-pyridone and other products. This rearrangement is the first example in a bicyclic system of this type where no second heteroatom in the ring undergoing rearrangement is able to assist the initial hydrolvtic ~leavage.~ It emphasises that the aromatic character of the bicyclic system is resident mainly in the triazole portion of the nucleus and confirms the electron-deficient nature of position 5 which is also clearly shown by n.m.r.data.4 This rearrangement may be regarded as being analogous p:N + to the Dimroth rearrangement characteristic of HONv certain pyrimidine derivatives? (a (Received October 1Sth 1964.) Department of Chemistry University of Louisville Kentucky U.S.A. Satisfactory analytical data were obtained for all products. J. D. Bower and G. R. Ramage J. 1957 4506,4510. a G. W. Miller and F. L. Rose J. 1963 5642 and references therein. K. T. Potts H. R.Burton T. H. Crawford and S. Thomas to be published. D. J. Brown,"Heterocyclic Compounds The Pyrimidines," J. Wiley-Interscience New York 1962 pp. 379,380. The Formation and Crystal Structure of DichIoro(dodeca-2,6,lO-triene-l,l2diyl)ruthenium(1v) By J. E. LYDON B. L. SHAW,and MARYR. TRUTER* J. K.NICHOLSON RECENTLY there has been much work on the poly- merisation of butadiene by transition metal com- plexes. Of particular interest is the formation of trans,trans,trans-cyclododeca- 1,5,9-triene using cer- tain complexes of nickel(0) such as bis(cyc1o-octa- 1 ,S-diene)nickel(O) as cata1ysts.l Wilkel has suggested that an unstable intermediate in this reaction is dodeca-2,6,1O-triene- 1,12-diylnickel(n) (I)from which trans,trans,,rans-cycl ododeca- 1,5,9- t ri en e forms by joining the two ends of the ligand together and is displaced from the nickel by more butadiene. We find that butadiene reacts with ruthenium tri- chloride in 2-methoxyethanol at 100" during 6 hr. to give a complex [RuCI~(C~H~)~] which forms yellow brown prisms decomposing with some melting at 210-220".Crystal structure analysis shows this compound to be dichloro(dodeca-2,6,1O-triene-1,12-diyl)ruthenium(rv) (II) with a structure ana- logous to the unstable intermediate (I) suggested by * School of Chemistry The University Leeds 2. G. Wilke Angew. Chem. (Internat. Edn.) 1963,2 105. Wilke; it therefore provides strong supporting evidence for his mechanism. X-Ray diffraction measurements were made on a crystal cooIed to 120"~. In a unit cell having a = 14.05 b = 8.63. c = 12.00A = 63.0" and space group P2,/a there are four molecules. The ruthenium and chlorine atoms were located from Patterson pro- jections down the b and c axes; because the ruthen- ium atom lies close to i,O,i,there was an ambiguity in its position which was resolved by a three-dimensional Patterson synthesis.The positions found corresponded to an approximately linear CI-Ru-Cl arrangement with each chlorine co-ordinated to one ruthenium atom. The carbon atoms were located by three-dimensional difference Fourier syntheses. No assumptions were made about the molecular struc- ture which was found to be as shown in (11). Aniso-tropic refinement is still proceeding at present R is 0.09for 1607 reflections. Our results show that a normal chain molecule has been formed by the catalytic trimerisation of buta- diene. The ruthenium atom is in a bipyramidal environment with the two chlorine atoms at the apices and the organic ligand occupying the equa- torial plane. The centres of the bonds C(l)-C(2) C(2)-C(3) C(6)-C(7) C(10)-C(1 l) and C(ll)-C(12) are coplanar.It is apparent that the groups of atoms C(1) C(2) and C(3) and C(lO) C(11) and C(12) are co-ordinated as n-ally1 groups; the complex is thus formally one of ruthenium(1v). The C(6)-C(7) bond PROCEEDINGS is approximately parallel to the Cl-Ru-C1 direction and is co-ordinated as an olefin. The complex is monomeric in benzene diamag- netic its infrared spectrum shows a medium intensity band at 1522 cm.-l (carbon-carbon double bond complexed to metal) and the nuclear magnetic resonance spectrum in deuterochloroform shows doublets at T 5-34 and 6.24 J = 7.5 and 11.2 c./sec. respectively due to the four terminal allylic hydro- gens; the rest of the spectrum is complex.Dichloro(dodeca -2,6,10 -triene -1,12 -diy1)-ruthenium(1v) on pyrolysis gives a mixture of pro- ducts including cis,trans,trans-and trans trans trans-cyclododeca-l,5,9-trienesand reacts with pyridine to give dichlorotetrapyridineruthenium(r1) and an un-identified hydrocarbon product. With S. D. Robinson we have also prepared a rhodium-butadiene complex [Rh,C14(C4H6),] and a similar iridium complex. (Received October 12th 1964.) Biosynthesisof the Amaryllidaceae Alkaloids. Part V.l Caffeic Acid and Protocatechuic Aldehyde as CG-c Precursors of Haemanthamine and Lycorhe By J. ZULALIAN and R. J. SUHADOLNIK* STUDIES concerned with the biosynthesis of the c&1 unit of the Amaryllidaceae alkaloids with whole plants and floral primordial tissue have established that [3-14C]phenylalanine,24 trans-[3-14C]cinnamic and p-[3-14C]coumaric acid1p5s6 are direct precursors.The isolation of [3H]lycorine from [3H]protocatechuic aldehyde and C3H]caffeic acid has been rep~rted.”~ These results provided the fist direct evidence that cinnamic acid and the hydroxyl- ated cinnamic acids are important intermediates in alkaloid biosynthesis and established the cinnamic acid pathway for the biosynthesis of ring A and the benzylic carbon atom of the Amaryllidaceae alka- loids.5 ,g We have synthesised [7-14C]protocatechuic alde- hyde and [3-14C]caffeic acid and report that both compounds serve as the C6-cl units of hzmantha- mine and lycorine. l-Rromo-3,4-niethylenedioxy-benzene was carbonated with [14C]carbon dioxide n-butyl-lithium being used.The resulting acid was converted into its acid chloride and reduced with lithium aluminium tri-t-butoxyhydride to yield [7-14C]piperonal. Treatment of the piperonal with phosphorous pentachloride afforded [7-14C]proto- catechuic aldehyde. This was then condenseds with malonic acid to give [3-14C]caffeic acid. The administration of the radioactive compounds and isolation and degradation of the alkaloids have been ~!escribed.~?~ The activities of the alkaloids and their degradation products are listed in the Table. The results of the degradation of the haeman- thamine from the [7-14C]pr~t~catechuic aldehyde and [3-14C]caffeic acid experiments show that 100 % of the radioactivity resides in 2-methyl-4,5-methyl- enedioxybiphenyl.The hydrastic anhydride obtained from the degradation of the lycorine retains 98 and 89% of the radioactivity respectively. These and earlier results1-’ conclusively establish the pathway for the biosynthesis of the C6-cl unit. The biosynthesis of hydroxybenzoic acids in higher plants from phenylpropaiioid compounds has * Research Laboratories Department of Biochemistry The Albert Einstein Medical Center Philadelphia Penn- sylvania. Part IV Suhadolnik and Zulalian Proc. Chem. SOC.,1963 216. Suhadolnik Fischer and Zulalian J. Amer. Chem. SOC.,1962 84 4348. Wildman Battersby and Breuer J. Amer. Chem. SOC.,1962 84 4599. Part 111 Suhadolnik Fischer and Zulalian Proc.Chem. SOC.,1963 132. Zulalian Fischer and Suhadolnik Abs. Meeting Amer. Chem. SOC. Los Angeles Calif. 1963 p. 30-L. * Part 11 Suhadolnik Fischer and Zulalian Biochem. Biophys. Xes. Comm. 1963 11 208. Archer Breuer Binks Battersby and Wildman Proc. Chem. SOC.,1963 168. Buck and Zimmerman in “Org. Synth.,” John Wiley and Sons Inc. New York 1943 Coll. Vol. 2 p. 549. Vorsatz J. prakt. Chem. 1936 145 265. DECEMBER 1964 423 Compounds [7-14C]-[3 -W]- recently been examined by ZenklO and Neish and Proto-Caffeic Towers.ll While the exact chemical nature of the catechuic acid compounds that are involved in the formation of aldehyde hydroxybenzoic acids is not known a /%oxidation of Activity Activity the aliphatic side-chain has been suggested for this (m pc/mmole) (m pc/mmole) conversion.Grisebach and Vollmer12 have suggested Hzmanthamine 13.5 0.87 that the formation of salicylic acid involves the Oxoha=manthamine 13.7 -p-oxidation of the coenzyme A ester of cinnamic Oxohamanthamin acid. The conversion of phenylalanine into proto- met hi odide 12.9 catechuic aldehyde involves deamination hydroxyla- N-Methyl-N-(6 phenyl- tions and possibly a /%oxidation of the aliphatic side- piperony1)glycine chain. Biologically these transformations may well sodium salt 13-7 0.88 proceed via the coenzyme A esters and/or glycosides 2-Methyl-4,5-methylene-of the intermediates and not via the free compounds dioxybiphenyl 14.8 0.68 as reported for the biosynthesis of the C,-C1 unit Lycorine 2.19 0.96 of the Amaryllidaceae alkaloids.Hydrastic anhydride 2-14 0.86 (Received September 28th 1964.) lo Zenk 2. Naturforsch. 1964 19b 83; Zenk and Muller ibid. p. 398. l1 El-Basyouni Chen Ibrahim Neish and Towers Phytochemistry 1964,3,485. lS Grisebach and Vollmer 2.Naturforsch. 1963 18b 753. VACANCIES ON COUNCIL 1965 INaccordance with the Bye-Laws of the Society notice is hereby given that the following vacancies on Council are to be filled at the Annual General Meeting to be held in Glasgow on Thursday April 8th 1965. Office No. of Names of Members who vacancies are to retire Honorary Secretary .. .. .. .. .. .. Vice-presidents who have not filled the Office of President .. .. THREE ONE Professor A. W. Johnson Professor D. H. R. Barton Professor J. Chatt Elected Ordinary Members of Council Constituency I .... .. .. .. (South-East England) Constituency I1 . . .. .. .. .. (Central and South-West England and South Wales) .. .. .. .. THREE ONE Professor B Lythgoe Dr. G. W. A. Fowles Professor A. R. Katritzky Dr. A. I. Vogel Dr. W. 3. Orville Thomas Constituency IV . . (North-East England) .. .. .. .. .. .. THREE Professor J. Baddiley Professor F. S. Dainton No vacancies arise in Constituencies 111 V and VI. Dr. T. J. King Members who are to retire are not eligible for re-election to the same office until a lapse of one year. In accordance with Bye-Laws 24 and 25 the Council has nominated Professor C. Eaborn to the Office of Honorary Secretary and Professor C. E. H. Bawn Professor A. W. Johnson and Professor R. S. Nyholm to the Office of Vice-presidents who have not filled the Office of President.Nominations by Fellows for the Office of Honorary Secretary and of Vice-president who has not filled the OEce of President should be made in writing and must be signed by at least twenty Fellows. Fellows resident in a constituency may nominate any Fellow resident in that constituency for election to the Council to fill a vacancy among Elected Ordinary Members of Council allotted to that constituency. Every such nomination must be in writing signed by at least fifteen Fellows resident in that constituency. Fellows may obtain forms of nomination from the General Secretary and should state the vacancy for which they are requested. Every nomination must relate to one vacant place only and must be accompanied by a signed declaration by the nominee that he is willing to accept office if elected.Nominations must be received by the Society not later than Sunday February 14th 1965. A. W. JOHNSON K. W. SYKES J. W. LMNETT December lst 1964. Honorary Secretaries. PROCE~RUGS NEWS AND ANNOUNCEMENTS Nobel Prize.-The Nobel Prize for Chemistry for 1964 has been awarded to Professor Dorothy Hodgkin for her work on X-Ray Crystallography. The Davy Medal.-The Royal Society has awarded the Davy Medal to Professor M. Calvin Honorary Fellow. Liaison Officer.-Dr. Edward Jones has agreed to act as a Chemical Society Liaison Officer at the Arthur D. Little Research Institute Edinburgh. Election of New Fellows.-1 22 Candidates were elected to the Fellowship in November 1964.Deaths.-We regret to announce the deaths of the following Mr. N. L. Allport (28.7.64) formerly Analyst to the Pool of London Authority; Mr. P. J. March (10.9.64) of the Shell Chemical Company Limited; Dr. 0.Rhys Howell (21.10.64) of Narberth Pembrokeshire; Mr. R. S. Ward (12.10.64) who was Principal Lecturer in Physical Chemistry at Kingston College of Technology; Dr. J.L. Williams (16.10.64) of Camberley Surrey. Anniversary Meetings 1966.-The Anniversary Meetings in 1966 will be held in Oxford from Tuesday March 29th until Thursday March 31st. The programme will include symposia consisting of invited papers on Intermolecular Forces and on Complexes of the Heavy Donor Atoms. In addition the second Robert Robinson Lecture will be given together with a series of lectures on contemporary topics in organic chemistry.Further details will be circulated to all Fellows in due course. International Sympmia.-An International Sym- posium on “Reaction Mechanisms of Inorganic Solids,” sponsored by The Chemical Society. will be held at the University of Aberdeen on July 11-16th 1966. It i~ hoped to bring together scientists of quite widely differing interests with the object of dis-cussing (and advancing the understanding of) the atomic movements or migrations which occur in reactions involving inorganic solids. The following topics will be treated 1. Methods of Study e.g. kinetics diffusion tech- niques crystallography. 2.Theoretical Aspects e.g. geometrical considera- tions the application of crystal field theory thermodynamics. 3. Mechanisms of Specific Classes of Reactions e.g. thermal decompositions devitrification of glasses reactions between solids polymorphic transitions redox processes. Each session will be briefly opened by an invited speaker; contributed papers will follow. Since the field is a rapidly developing one the above list of topics is not meant to be exhaustive and any relevant contributions will be considered. Anyone wishing to contribute a paper to the symposium should write to the Chairman of the Programme Committee Dr. H. F. W. Taylor Department of Chemistry University of Aberdeen Old Aberdeen Scotland. Further particulars will be available in May 1965 from the General Secretary The Chemical Society Burlington House London W.1. Formal application will not be required until much nearer the date of the symposium. An International Symposium on “The Alkali Metals” will be sponsored by the Chemical Society and held at the Chemistry Department University of Nottingham on July 19th-21st 1966. The Sym- posium is intended to reflect recent developments in) the chemistry of the alkali metals and the subjects to be discussed will include for example A. The physical properties of the alkali metals in the solid liquid or gaseous states. B. Those properties concerned with electron trans- fer ionisation potential atomic dimensions etc. C. Solutions of metals and non-metals in the liquid alkali metals; the nature and behaviour of dissolved species.D. Solutions of the alkali metals in organic and inorganic solvents and in molten salts. E. The chemistry of compounds of the alkali metals provided that the features of interest relate primarily to the alkali-metal atoms or ions. These topics will be introduced and reviewed in invited papers by experts in the respective fields. Contributed Papers A limited number of short contributed papers can also be considered for inclusion in the programme. Those who wish to present a paper at the meeting should communicate with the Chairman of the Pro- gramme Committee Professor C. C. Addison Department of Chemistry The University Notting- ham England as soon as possible and in any case not later than December 31st 1965 indicating the title and the general scope of their paper.Those whose papers are accepted will be required to submit a short abstract typed to a prescribed format for reproduction and circulation to all participants before the meeting. All invited lectures and some of the contributed papers to be selected by the Programme Committee as having a direct bearing on the subject matter of the invited lectures will be published by the Chemical Society in the series of Special Publications. Advance registration for attendance at the Symposium is necessary and application forms will be available in April 1966. Those who wish to be kept informed should apply to the General Secretary The Chemical Society Burlington House London w.1.DECEMBER 1964 Symposia.-A One-day Symposium on Modern Aspects of Organic Chemistry will be held at Hull on January 23rd 1965. Further enquiries should be addressed to Professor N. B. Chapman Chemistry Department The University Hull. A Symposium on the Chemistry of Polymerisation Processes organised by the Plastics and Polymer Group of the Society of Chemical Industry will be held in London on April 22nd-23rd 1965. Further enquiries should be addressed to Dr. W. R. Moore c/o Department of Chemical Technology Bradford Institute of Technology Bradford 7 Yorkshire. (Correction to particulars already announced Pro-ceedings 1964 373.) World Directory of Crystallographers.-A third edition of this Directory is being prepared under the editorship of Dr.D. W. Smits of Gronhgen Netherlands and biographical information is being collected for each country by a sub-editor. It is intended to include in the Directory all practising crystallographers including graduate students. Read- ers in the United Kingdom who consider their names should be included in the Directory but who have not received a questionnaire are requested to write to Dr. P. T. Davies “Shell” Research Limited Thornton Research Centre P.O. Box 1 Chester. Personal.-Mr. M. J. Baillie has been awarded a Glasgow Fellowship for the year 1964-65 by the Trustees of the Ramsay Memorial Fellowships. Dr. D. W. Bassett has been appointed Lecturer in the Department of Chemistry at the Imperial College of Science and Technology London.Mr. L. W. Blundell has been appointed Vice- President of the British Road Tar Association for 1964-65. Dr. A. D. Buckingham Lecturer in Inorganic Chemistry in Oxford University has been appointed Professor in Theoretical Chemistry at the University of Bristol. Projessor M. Calvin of California University Berkeley has been appointed to the George Eastman Visiting Professorship for the academic year 1967-68 at the University of Oxford. Dr. W. C. Gifpiiz has been appointed a Director of the Steetley Company Limited and to the position of Group Technical Director. Sir Cyril Hinshefwood has been elected President of the British Association. Dr. F. D. M. Hocking has retired from service with the Royal Cornwall Infirmary Truro.Dr. T. F. Holley formerly at the Welsh National School of Medicine has been appointed Senior Grade Biochemist at the Group Pathology Labora- tory St. Tydfils Hospital Merthyr Tydfil. Mr. L. C. Macmahon has been appointed Managing Director of Yorkshire Tar Distillers Limited. He has accepted an invitation to join the Board of the holding company Yorkshire Tar Corporation Limited. Dr. J. F. Mathews has been appointed Technical Development Officer at the Central Electricity Generating Board at Retford. D.S.I.R. has made a grant of $25,330 to Man- Chester College of Science and Technology for the use of Dr. I. A. Menzies to support research in corrosion and protection.Professor F. Morton Head of Chemical Engineer- ing at the Manchester College of Science and Technology has been appointed Acting Principal until December 1965. Dr. S. S. Sandhu has been appointed Reader in Chemistry in the Panjab University Chandigarh. Mr. H. Slromberg has been appointed a Director of Joseph Crosfield and Sons Limited. Dr. R. G. Sutherland has been appointed an Imperial Chemical Industries Research Fellow in Chemistry at Queen’s College University of St. Andrews. Dv. E. M. Wilson formerly a N.A.T.O. Research Fellow at Imperial College London has been appointed a Scientific Officer in the Chemistry Unit of Glaxo Research Limited. PROCEEDINGS PROGRAMME OF MEETINGS JANUARY TO JUNE 1965* Anniversary Meetings 1965 THEAnniversary Meetings of the Society will be held in Glasgow on April 7th to 9th.A programme of the meetings will be sent separately to all Fellows. London Thursday January 14th 1965 at 6 p.m. Faraday Lecture “Some Aspects of the Kinetics and Analyses of Very Fast Chemical Reactions,” by Professor R. G. W. Norrish Sc.D. F.R.S. To be given in the Lecture Theatre The Royal Institution 21 Albeniarle Street W.l. Thursday February 4th at 6 p.m. Tilden Lecture “Syntheses in the Cardiac-active Steroid Field,” by Professor F. Sondheimer Ph.D. A.R.C.S. To be given in the Physics Lecture Theatre Imperial College of Science and Technology South Kensington S.W.7. Thursday February 25th at 6 p.m. Centenary Lecture “Biosynthesis and Function of Biotin-enzymes,” by Professor F.Lynen. To be given in the Edward Lewis Lecture Theatre Middle- sex Hospital Medical School W. 1. Thursday March 25th at 2 p.m. Symposium on the Chemistry of Organornetallic Compounds. To be held in the Edward Lewis Lecture Theatre h4iddlesex Hospital Medical School W.l. Joint Meeting with the Royal Institute of Chemistry. Thursday May 6th at 6 p.m. Centenary Lecture “Energy Distribution among Re- action Products and Infrared Chemiluminescence,” by Professor J. C. Polanyi D.Sc. To be given in the Physics Lecture Theatre Imperial College of Science and Technology South Kensington S.W.7. Thursday June 3rd at 6 p.m. Discussion Meeting to be held in the Rooms of the Society Burlington House W.1. Aberdeen (Joint Meetings with the Royal Institute of Chem-istry and the Society of Chemical Industry to be held in the Biochemistry Lecture Theatre Marischal College unless otherwise stated.) Monday January 18th 1965 at 8 p.m. A Discussion on Food Additives. Opened by Dr. M. Pyke and Dr. E. Owen. To be held in the Senior Common Room Marischal College. Monday February lst at 8 p.m. Lecture “Variants in the Structural Polysaccharides of Plants,” by Professor R. D. Preston D.Sc. Ph.D. F.R.S. Thursday February 25th at 8 p.m. Lecture “Some Aspects of Activity at the Glaxo Factory Montrose,” by Mr. R. J. Nicholls. Thursday April 29th at 8 p.m. Lecture “The Chemistry of Some Compounds Con- taining a Metal-Carbon Bond,” by Professor J.Lewis Ph.D. D.Sc. Monday May loth at 8 p.m. Centenary Lecture “Energy Distribution Among Re- action Products and Infrared Chemiluminescence,” by Professor J. C. Polanyi D.Sc. To be given in the Chemistry Department The University. (This is not a Joint Meeting.) Aberystwyth (Joint Meetings with the University College of Wales Chemical Society to be held in the Edward Davies Chemical Laboratory.) Thursday January 21st 1965 at 5 p.m. Lecture “Tetraterpenes,” by Professor B. C. L. Weedon D.Sc. A.R.C.S. Thursday February 4th at 5 p.m. Lecture “Free and Paired Ions in Chemical Re- actions,” by Professor W. F. K. Wynne-Jones D.Sc. Thursday February 18th at 5 p.m. Lecture “Structure and Photochemical Reactivity,’’ by Professor J.N. Pitts. Thursday March 4th at 5 p.m. Lecture “The Hydrogen Bond,” by Dr. L. Bellamy. Thursday March 18th at 5 p.m. Lecture “Electrochemistry of the Bacterial Surface,” by Dr. A. M. James. Tuesday May 4th at 5 p.m. Centenary Lecture “Energy Distribution among Re- action Products and Infrared Chemiluminescence,‘’ by Professor J. C. Polanyi D.Sc. Birmingham (Joint Meetings with the University Chemical Society to be held in the Chemistry Department The University unless otherwise stated.) Friday January 15th 1965 at 4.30 p.m. Lecture “The Discovery of O$[PtF,]- and Noble Gas Chemistry,” by Professor N. Bartlett. Friday February 19th at 4.30 p.m. Lecture “Bonds and Orbitals,” by Professor H. C. Longuet-Higgins M.A. D.Phil.F.R.S. Friday February 26th at 5.30 p.m. Lecture “Dienyl Complexes of the First-row Transi- tion Elements,” by Professor P. L. Pauson Ph.D. F.R.S.E. Joint Meeting with the Chemical Society of the College of Advanced Technology to be held at the College of Advanced Technology Gosta Green. * Preprints of this programme can be obtained from the General Secretary The Chemical Society Burlington House, London W. 1. DECEMBER 1964 Friday May 14th at 4.30 p.m. Lecture “Some Applications of Reaction Kinetics to Chemical Analyses,” by Professor H. M. N. H. Irving M.A. D.Sc. Rrighton (Joint Meetings with the University Chemical Society to be held in the Chemical Laboratory The University of Sussex.) Monday January llth 1965 at 5.15 p.m.Lecture to be given by Dr. C. A. Vernon. Monday January 25th at 5.15 p.m. Lecture “Bonds and Orbitals,” by Professor H. C. Longuet-Higgins M.A. D.Phil. F.R.S. Monday February 8th at 5.15 p.m. Lecture “Modern Applications of Infrared Spectro- scopy to Molecular Dynamics,” by Professor N. Sheppard M.A. Ph.D. Monday February 22nd at 5.15 p.m. Lecture to be given by Professor W. D. Ollis Ph.D. Monday March 8th at 5.15 p.m. Lecture “Explosives,” by Dr. B. D. Shaw. Bristol (Joint Meetings with the Society of Chemical Industry and the Royal Institute of Chemistry to be held in the Department of Chemistry The University unless otherwise stated.) Thursday January 21st 1965 at 5.30 p.m. Lecture “Organometallic Co-ordination Chemistry of the Group I1 Elements,” by Professor G.E. Coates D.Sc. F.R.I.C. Also joint with the Student Chemical Society. Friday January 22nd at 5.30 p.m. Lecture “The Discovery of O,+[PtF,]- and Noble Gas Chemistry,” by Professor N. Bartlett. Thursday January 28th at 6.30 p.m. Short Papers. Thursday February 4th at 6.30 p.m. Lectures “Water Vapour and Gas Permeability of Protective Wraps,” and “Some Aspects of Codex AZin7entarirrs,” by Mr. J. R. Silby and Dr. Z. Hybs. Also joint with the Food Group. Thursday February 11 th at 5.30 p.m. Lecture “Modern Aspects of Structure Determina- tion,” by Professor W. D. Ollis Ph.D. Also joint with the Student Chemical Society. Tuesday February 16th at 7 30 p.m Lecture “The Chemistry of Colour Photography,” by Dr.L. A. Williams. To be given at Gloucester. Thursday March 4th at 6.30 p.m. Lecture “Research in Brewing,” by Dr. A. K. Mills. Also joint with the Institute of Fuel Cambridge (Joint Meetings with the University Chemical Society to be held in the University Chemical Laboratory Lensfield Road unless otherwise stated.) Tuesday February 2nd 1965 at 8.30 p.m. Lecture “The Discovery of Oi[PtF,]- and Noble Gas Chemistry,” by Professor N. Bartlett. Friday February 26th at 8.30 p.m. Lecture “High Pressure Chemistry,” by Professor G. J. Hills Ph.D. D.Sc. Tuesday March 9th at 6.15 p.m. Lecture “Synthetic Studies in Phospholipid Chem- istry,” by Dr. R. H. Gigg. To be given at Mander College Bedford. This is not a joint meeting.Cardiff (Meetings to be held in the Department of Chemistry University College Cathays Park Cardiff.) Monday February ISth 1965 at 5 p.m. Lecture “Studies on the BicycIo[3,3,1 Jnonane Ring System,” by Professor R. A. Raphael D.Sc. F.R.S.E. F.R.S. Monday March 8th at 5 p.m. Lecture “Spectrographic Studies of Transient Chemical Species formed in Irradiated Systems,” by Dr. J. W. Boag. Dundee Wednesday February 3rd 1965 at 4.30 p.m. Lecture “The Structural Chemistry of Volatile Silicon Compounds,” by Dr. E. A. V. Ebsworth. To be given in the Chemistry Department Queen’s College. Durham (Joint Meetings with the University Chemical Society to be held in the Science Laboratories South Road unless otherwise stated.) Monday February lst 1965 at 5 p.m.Lecture “Bivalent Carbon-Fact or Fancy?” by Professor R. N. Haszeldine M.A. D.Sc. Wednesday February loth at 3 p.m. Meeting for the Reading of Original Papers on Reaction Mechanism. Joint Meeting with the Chemical Societies of Newcastle and Tees-side. Monday February 22nd at 5 p.m. Lecture “Steric Hindrance and Analytical Chem- istry,” by Professor H. M. N. H. Irving M.A. D.Sc. Monday March 8th at 5 p.m. Lecture “Bonds and Orbitals,” by Professor H. C. Longuet-Higgins M.A. D.Phil. F.R.S. Also joint with the Royal Institute of Chemistry. Monday March 15th at 5 p.m. Lecture “The Chemical Versatility of Triethyl Phosphite,” by Professor J. I. G. Cadogan D.Sc. Ph.D. Edinburgh Tuesday January 19th 1965 at 4.30 p.m.Lecture “lonic Polymerisation,” by Professor C. E. H. Bawn C.B.E. F.R.S. Joint Meeting with the University Chemical Society to be held in the Department of Chemistry The University. Thursday January 21st at 7.30 p.m. Lecture “Organic Semiconductors,” by Professor D. D. Eley O.B.E. F.R.S. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in the Heriot-Watt College. Thursday February 25th at 7.30 p.m. Lecture “Chemistry of the Vitamin BI2-grOup,” by Professor A. W. Johnson Sc.D. Ph.D. Joint Meet- ing with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in the Heriot-Watt College. Tuesday March 2nd at 4.30 p.m. Lecture “Studies in the Carotenoid Field,” by Professor B.C. L. Weedon Ph.D. D.Sc. Joint Meeting with the University Chemical Society to be held in the Department of Chemistry The University. Tuesday May 4th at 4.30p.m. Pedler Lecture “The Widening Outlook in Aromatic Chemistry,” by Professor W. Baker M.A. D.Sc. F.R.S. To be given in the Department of Chemistry The University. Exeter (Meetings to be held in the Washington Singer Laboratories Prince of Wales Road.) Friday February 26th 1965 at 5.15 p.m. Lecture “Simple Inorganic Radicals,” by Professor M. C. R. Symons Ph.D. D.Sc. Friday March 5th at 5.15 p.m. Lecture “A Chemical Basis for Human Blood Group Specificity,” by Professor W. T. J. Morgan C.B.E. F.R.S. Glasgow Thursday January 21st 1965 at 4 p.m.Lecture “Alkyl and Aryl Derivatives of Transition Metals,” by Professor J. Chatt M.A. Sc.D. F.R.S. Joint Meeting with The Andersonian Chemical Society to be held in the Chemistry Department the University of Strathclyde. Thursday February 18th at 4 p.m. Lecture “An Aspect of Nucleic Acid Chemistry,” by Dr. D. M. Brown. Joint Meeting with the Al- chemists Club to be held in the Chemistry Depart- ment The University. Monday February 22nd at 4 p.m. Centenary Lecture “Biosynthesis and Function of Biotin-enzymes,” by Professor F. Lynen. To be given in the Chemistry Department the University of Strathclyde. Friday March 12th at 4 p.m. Annual General Meeting for Local Fellows. Followed by Meeting for Reading of Original Papers PROCEEDINGS “The Electronic Effects of Substitution in Benzene,” by Dr.G. Doggett and Professor D. P. Craig D.Sc. “A Novel Method of Making Catalysts,” by Dr. S. J. Thomson and Dr. G. Webb. “Self Diffusion in Organic Crystals,” by Mr. G. M. Hood and Mr. J. N. Sherwood. To be held in the Chemistry Department The University. Hull (Joint Meetings with the University Student Chem- ical Society to be held in the Chemistry Department The University.) Thursday January 21st 1965 at 4 p.m. Pedler Lecture “The Widening Outlook in Aromatic Chemistry,” by Professor W. Baker M.A. D.Sc. F.R.S. Thursday February 18th at 4 p.m. Lecture “New Developments in Free Radical Chemistry,” by Professor C. H. Bamford M.A.Sc.D. Thursday March 4th at 4 p.m. Lecture “Some Aspects of the Chemistry of Free Radicals,” by Dr. G.A. Williams. Keele (Meetings to be held in the Department of Chemistry The University.) Monday February 8th 1965 at 5 p.m. Tilden Lecture “Syntheses in the Cardiac-active Steroid Field,” by Professor F. Sondheimer Ph.D. A.R.C.S. Monday February 22nd 1965 at 5 p.m. Lecture “The Recent Chemistry of Gallium,” by Professor N. N. Greenwood Ph.D. Sc.D. Joint Meeting with the University Chemical Society. Monday March lst at 5 p.m. Lecture “Structure and Biosynthesis,” by Professor A. R. Battersby D.Sc. Ph.D. Joint Meeting with the University Chemical Society. Leeds (Meetings to be held in the Chemistry Lecture Theatre The University.) Thursday February 11 th 1965 at 6 p.m.Lecture “The Stabilisation of Low-valent States of the Transition Metals by Tertiary Phosphines,” by Professor J. Chatt M.A. Sc.D. F.R.S. Joint Meet- ing with the University Union Chemical Society. Thursday March 4th at 6 p.m. Lecture “Structure and Photochemical Reactivity,” by Professor J. N. Pitts jun. Wednesday May 12th at 6.30 p.m. Official Meeting and Centenary Lecture. “Energy Distribution among Reaction Products and Infrared Chemiluminescence,” by Professor J. C. Polanyj D.Sc. DECEMBER 1964 Leicester Thursday February 18th 1965 at 4.30 p.m. Lecture “Field Ion Microscopy and Surface Chem- istry,” by Professor J. S. Anderson M.A. Ph.D. F.R.S. Joint Meeting with the Loughborough Col- lege of Technology Chemical Society to be held in the Union Building Lecture Theatre Loughborough College of Technology.Thursday February 18th at 5 p.m. Lecture “Chemistry and Atomic Energy Today,” by Dr. R. Spence C.B. F.R.S. Joint Meeting with the Lejcester College of Technology Chemical Society to be held in the College of Technology Leicester. Monday March 15th at 4.30 p.m. Lecture “Nuclear Fingerprints-Some Applications of the Mossbauer Effect,” by Professor N. N. Greenwood Ph.D. Sc.D. Joint Meeting with the Leicester University Chemical Society to be held in the Department of Chemistry The University. Liverpool (Joint Meetings with the Society of Chemical Industry the Royal Institute of Chemistry and the Student Chemical Society to be held in the Donnan Laboratories The University.) Thursday January 28th 1965 at 5 p.m.Lecture “Aspects of the Chemistry of Taxines,” by Professor B. Lythgoe MA. Ph.D. F.R.S. Thursday February 25th at 5 p.m. Lecture “The Nature of Reactive Intermediates in Cationic Polymerisation,” by Professor D. C. Pepper MA. Ph.D. Thursday May 13th at 5 p.m. Centenary Lecture and Official Meeting “Energy Distribution among Reaction Products and Infrargd Chemiluminescence,” by Professor J. C. Polanyi D.Sc. Manchester (Meetings to be held in Lecture Theatre H 10 Renold Building The Manchester College of Science and Technology unless otherwise stated.) Thursday January 21st 1965 at 6.30 p.m. Lecture “Some Recent Developments in the Chemistry of Higher Co-ordination Numbers,” by Professor R.S. Nyholm D.Sc. F.R.S. Thursday February 11 th at 6.30 p.m. Lecture “Applications of Electron Spin Resonance Spectroscopy in Organic Chemistry,’’ by Dr. R. 0.C. Norman. Joint Meeting with the University of Manchester Faculty of Technology Chemical Society. Tuesday February 23rd at 6.30 p.m. Centenary Lecture “Biosynthesis and Function of Biotin-enzymes,” by Professor F. Lynen. Thursday March 18th at 6.30 p.m. Lecture “Electricity and Flames,” by Dr. T. M. Sugden F.R.S. Wednesday April 14th at 10 a.m. Symposium on “Chemical Aspects of the Protection of Textiles from Heat and Fire.” Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in Lecture Theatre C 9 Renold Building The Manchester College of Science and Technology.Newcastle-upon-Tyne (Meetings to be held in the School of Chemistry The University.) Tuesday January 19th 1965 at 6.30 p.m. Lecture “The Mossbauer Efkct a New Technique in Pure and Applied Chemistry,” by Professor N. N. Greenwood Ph.D. Sc.D. Joint Meeting with the Royal Institute of Chemistry. (Please note change of lectrire from that show in September Proceedings for this date.) Tuesday January 26th at 5.15 p.m. Lecture “The Discovery of O$[PtF,]-and Noble Gas Chemistry,’’ by Professor N. Bartlett. Tuesday February 9th at 4p.m. Lecture “The Chemical Structure of Antibodies,” by Professor R. R. Porter Ph.D.F.R.S. Friday February 12th at 5.15 p.m. Bedson Club Lecture “Organometallic Co-ordina- tion Chemistry of some Group I1 Elements,” by Professor G. E. Coates D.Sc. F.R.I.C. Tuesday February 23rd at 5.15 p.m. Lecture “Some Aspects of Polymerisation and Free Radical Chemistry,” by Professor J. C. Robb D.Sc. Friday February 26th at 5.15 p.m. Bedson Club Lecture “The Chemistry of the Stars,” by Professor W. R. Hindmarsh M.A. D.Phi1. Friday March 12th at 5.15 p.m. Bedson Club Lecture “Gastrin a Peptide Hor- mone,” by Professor G. W. Kenner Sc.D. F.R.S. Northern Ireland (Joint Meetings with the Royal Institute of Chem- istry the Society of Chemical Industry and the Andrews Club to be held in the Department of Chemistry David Keir Building Queen’s University Belfast.) Thursday January 14th 1965 at 7.45 p.m.Tilden Lecture “Syntheses in the Cardiac-active Steroid Field,” by Professor F. Sondheimer Ph.D. A.R.C.S. Tuesday March 2nd at 7.45 p.m. Lecture “Chemical Application of the Mossbauer Effect,” by Professor N. N. Greenwood Ph.D. Sc.D. North Wales (Meetings to be held in the Chemistry Department University College of North Wales Bangor.) Wednesday February loth 1965 at 5.30 p.m. Lecture “Infrared Spectrometry and Surface Potential Studies of the Oxidation of Carbon Mon- oxide at a Platinum Surface,” by Professor F. C. Tompkins D.Sc. F.R.S. Thursday March 4th at 5.30 p.m. Lecture “The Role of the Chemist in the Pharma- ceutical Industry,” by Dr.H. J. Barber F.R.I.C. Norwich (Meetings to be held in Lecture Room 2 The University of East Anglia Wilberforce Road unless otherwise stated.) Thursday January 28th 1965 at 7.30 p.m. Lecture “Infrared Spectroscopy and Molecular Dynamics,” by Professor N. Sheppard M.A. Ph.D. Joint Meeting with the Royal Institute of Chemistry to be held at the Norwich City College Ipswich Road Norwich. Thursday February 4th at 5.30 p.m. Lecture “Chemistry for Profit,” by Dr. J. W. Barrett. Thursday February 18th at 5.30 p.m. Lecture “New Bonds for Old,” by Dr. D. S Urch. Thursday March 18th at 5.30 p.m. Lecture “Structural Chemistry of Volatile Silicon Compounds,” by Dr. E. A. V. Ebsworth M.A. Thursday May 13th at 5.30 p.m. Lecture “Chemistry of the Electron,” by Professor F.S. Dainton M.A. Sc.D. F.R.S Thursday June 3rd at 5.30 p.m. Lecture “Chemical Approaches to Hypertension,” by Dr. A. M. Monro M.A. Nottingham (Joint Meetings with the University Chemical Society to be held in the Large Lecture Theatre the Department of Chemistry The University.) Tuesday January 12th 1965 at 5 p.m. Lecture “Behind the Scenes with the Public Analyst,’’ by Mr. E. R. W. Fogden B.Sc. Tuesday January 26th at 5 p.m. Lecture to be given by Dr. T. M. Sugden Sc.D. F.R.S. Tuesday February 9th at 5 p.m. Lecture to be given by Professor W. D. Ollis Ph.D. Wednesday February 19th at 5 p.m. Official Meeting and Centenary Lecture “Biosyn- thesis and Function of Biotin-enzymes,” by Professor F.Lynen. Tuesday February 23rd at 5 p.m. Lecture to be given by Professor D. P. Craig Ph.D. F.R.I.C. Oxford Monday January 25th 1965 at 8.30 p.m. Lecture “Total Synthesis of Sex Hormones and Analogues,” by Professor A. J. Birch D.Phil. F.R.S. Joint Meeting with the Alembic Club to be PROCEEDINGS held in the Inorganic Chemistry Laboratory South Parks Road. Reading (Joint Meetings with the Royal Institute of Chem-istry and the University Chemical Society.) Tuesday February 2nd 1965 at 5.30 p.m. Lecture “The Future of Chemical Publications,” by Dr. R. S. Cahn F.R.I.C. To be given in the Large Chemistry Lecture Theatre The University. Monday March 8th at 5.15 p.m. Lecture “Inert Gases,” by Professor C. A. Coulson M.A. D.Sc.F.R.S. To be given in the Zoology Lecture Theatre The University. Republic of Ireland (Meetings to be held in the Department of Chemistry Trinity College Dublin unless otherwise stated.) Wednesday January 13th 1965 at 5.30 p.m. Tilden Lecture “Syntheses in the Cardiac-active Steroid Field,” by Professor F. Sondheimer Ph.D. A.R.C.S. Friday February 19th at 7.45 p.m. Lecture “Gastrin A Peptide Hormone,” by Professor G. W. Kenner Ph.D. Sc.D. F.R.S. Joint . Meeting with the Werner Society. Friday February 26th at 7.45 p.m. Lecture “Analytical Chemistry in Industrial Re-search,” by Mr. G. B. Crump. Joint Meeting with the Werner Society. Wednesday March 3rd at 7.45 p.m. ZRcture “Chemical Applications of the Mossbauer Effect,” by Professor N.N. Greenwood Ph.D. Sc.D. Tuesday March 23rd at 8.30 p.m. Qcture “Epichemistry Epoxides Episulphides and Epimines,” by Dr. L. Hough. To be given at University College Galway. Wednesday March 24th at 5.30 p.m. Lecture “Epichemistry Epoxides Episulphides and Epimines,” by Dr. L. Hough. Wednesday May 5th at 5.30 p.m. Lecture “Some Scientific Aspects of Meat,” by Dr. R. A. Lawrie. Joint Meeting with the Institute of Chemistry of Ireland The Royal Institute of Chem-istry and the Society of Chemical Industry. The above lecture by Dr. R. A. Lawrie will also be given on Friday May 7th at 8 p.m. at University College Cork; and Monday May loth at 8.30 p.m. at University College Galway at Joint Meetings. St. Andrews (Joint Meetings with the University Chemical Society to be held in the Chemistry Department St.Salvator’s College.) DECEMBER 1964 Thursday January 21st 1965 at 5.15 p.m. Lecture “Formation of Metal Complexes and Ion Pairs in Solution,” by Dr. G. H. Nancollas. Thursday February llth at 5.15 p.m. Lecture “Some Organometallic Derivatives of Transition Elements,” by Professor P. L. Pauson Ph.D ,F.R.S.E. Thursday February 25th at 5.15 p.m. Lecture “Chemistry of the Noble Gases,” by Dr. R. D. Peacock. Thursday April 22nd at 5.15 p.m. Lecture “Use of Mass Spectrometry in Organic Chemistry,” by Dr. J. Beynon. Thursday April 29th at 5.15 p.m. Lecture “Chemistry and Clothing,” by Dr. J. Honeyman. Also joint with the Royal Institute of Chemistry.Sheffield (Joint Meetings with the Royal Institute of Chem-istry and the Student Chemical Society to be held in the Department of Chemistry The University unless otherwise stated.) Wednesday January 27th 1965 at 4.30 p.m. Lecture “The Discovery of Oi[PtF,]-and Noble Gas Chemistry,” by Professor N. Bartlett. (This is not a Joint Meeting.) Friday February 19th at 4.30 p.m. Lecture “Early Days in the Application of Electronic Theory to Organic Chemistry,” by Sir Robert Robinson O.M. F.R.S. Thursday March 18th at 4.30 p.m. Lecture “Phenolic Alkaloids,” by Dr. G. W. Kirby. Thursday May 6th at 4.30 p.m. Lecture “Vitamin B, Recent Experiments,” by Professor Dorothy Hodgkin Ph.D. F.R.S. Thursday May 20t11 at 4.30 p.m.Lecture “Some Recent Developments in the Chemistry of Compounds Containing Metal-to-Metal Bonds,” by Professor R. S. Nyholm D.Sc. F.R.S. Southampton (Meetings to be held in the Lecture Theatre the Chemistry Department The University unless otherwise stated. ) Friday January 15th 1965 at 5 p.m. Lecture “Shock Waves in Chemistry,” by Professor J. N. Bradley Ph.D. A.R.I.C. Joint Meeting with the Royal Institute of Chemistry. Friday February 12th at 5 p.m. Lectures “Metal-to-Metal Bonds in Inorganic Compounds,” by Professor R. S. Nyholm D.Sc. 411 F.R.S. Joint Meeting with the Royal Institute of Chemistry. Friday February 12th at 7 p.m. Lecture “The Structure of D.N.A.” by Dr. D. M. Brown. To be given in Lecture Room H 9 College of Technology Portsmouth.Wednesday March 24th at 7 p.m. Lecture “Anaesthetics,” by Dr. J. Haworth. To be given in Lecture Room H 9 College of Technology Portsmouth. Swansea (Joint Meetings with the Student Chemical Society to be held in the Large Lecture Theatre the Depart- ment of Chemistry The University.) Monday January 25th 1965 at 4.30 p.m. Lecture “Mechanisms of Oxidation of Organic Compounds by Ions of Transition Metals,” by Professor W. A. Waters Ph.D. D.Sc. Monday February 15th at 4.30 p.m. Lecture “The Chemist’s Role in the Brewing Industry,” by Dr. J. Todd. Monday March 15th at 4.30 p.m. Lecture “The Mechanism of Paraffin Pyrolysis,” by Dr. J. H. Purnell. Tees-side (Joint Meetings with the Royal Institute of Chem-istry and the Society of Chemical Industry to be held at the Constantine College of Technology Middlesbrough unless otherwise stated.) Wednesday January 20th 1965 at 8 p.m.Research Symposium on Heterocyclic Systems with Quaternary Bridgehead Nitrogen Atoms. Speaker Dr. E. E. Glover A.R.l.C. Wednesday January 27th at 7.45 p.m. Scientific Film Show to be held at the Synthonia Theatre Balasis Lane Billingham. Thursday February 11 th at 8 p.m. Lecture “The Industrial Uses of Starch Degrading Enzymes,” by Dr. 1. D. Fleming. To be given at the College of Further Education Cleveland Avenue Darlington. Tuesday February 23rd at 8 p.m. Lecture “Some Recent Work on the Lighter Actinides,” by Dr. K. W. Bagnall. Wednesday April 14th at 8 p.m.Lecture “Electron Resonance and its Application to Chemical Problems,” by Professor D. J. E. lngram M.A. D.Sc. To be given at the Vane Arms Hotel High Street Stockton-on-Tees. Wednesday May 26th at 8 p.m. Lecture “Research and Teaching at a New Univer- sity,” by Professor A. R. Katritzky M.A. Ph.D. 432 PROCEEDINGS OBITUARY NOTICES R. N. LACEY 1922-1964 THEdeath of Dick Lacey after a long and painful illness on July 31st 1964 at his home in Camberley Surrey brought to a tragically early end the life of a gifted organic chemist. Quiet and unassuming though he was his qualities of leadership integrity and honour endeared him to his friends and col- leagues just as they respected and admired him for the quality of his work the imagination and inven- tion upon which it was founded and the meticulous care and attention to detail with which it was carried out.Born in London on May 18th 1922 he graduated with 1st Class Honours in Chemistry at the Royal College of Science in 1942 after leaving Highbury County School. One of the best students of his year he accepted an invitation to join the late Professor Sir Ian Heilbron’s research team at the college and there he spent the next two years studying the in-tricacies of poly-unsaturated compounds and their synthesis. This work which had its origins in the search for a synthetic route to Vitamin A gave rise to two series of papers in the Journal of the Chemical Society “Studies in the Polyene Series” and “Re- searches on Acetylene Compounds,” and of several of these papers Dr.Lacey was a co-author. Under the title “Polyene Synthesis Employing Acetylenic Compounds” the thesis he submitted for his Ph.D. describes the condensation of methyl prop-2-ynyl ether with a$-unsaturated carbonyl compounds and the anionotropic rearrangements of acetylenic alcohols and glycols. After spending a year with Organon Ltd. he joined the Distillers Company Ltd. Central Research and Development Department in August 1945 as a research chemist and during the next four years he worked on a variety of topics. One of these was hydrocarbon oxidation and he contributed to the researches which gave birth to the now widely used and highly successful “Phenol from Cumene” pro- cess.The first patent bearing his name as inventor concerns the conversion of aromatic hydroperoxides to phenols and ketones. It was during this phase of Dr. Lacey’s career that he first gained experience of chemical manufacture for he spent some time as a member of a shift team operating the acetic an- hydride pilot plant at Salt End Hull. In August 1949 he was transferred to the Dis- tillers Company’s subsidiary British Industrial Sol-vents Ltd. at Hull and the next ten years saw him playing steadily more and more important roles demanding ever increasing responsibility; Super- intendent of Research Laboratories (1954) Deputy Manager Development Department (1957) Manager of the Pilot Plant Group (1958). This decade was one of great change and expansion at the Salt End factory and its Development Department.Major improvements were made in the then existing factory processes new processes were devised for many products and a number of new products were added to the manufacturing range a revolution in fact in which Dick Lacey had a notable share. His recognition of the complementary roles of produc- tion and research and development stimulated his interest in chemical engineering and in 1951 he was awarded his A.M.I.Chem.E. to which he added the Diploma in Applied Economics of Hull University in 1957. Despite his growing responsibilities and the inevitable managerial and administrative demands now being made upon him he spent as much of his time as possible at the bench and here he continued to demonstrate his exceptional abilities as a practical research chemist.Keten diketen and the derivatives of acetoacetic acid were his especial loves for many years as a series of ten papers “Derivatives of aceto- acetic acid Part I-X” in the Chemical Society’s Journal and a number of patents amply testify. As an accepted authority on the subject he contributed the chapter on “Ketene in Organic Synthesis” in “Advances in Organic Chemistry 1960,” edited by his contemporary from his Royal College of Science days Professor R. A. Raphael. Formaldehyde chem- istry also caught his imagination and led him to such topics as acrylates methyl vinyl ketone methyl isopropenyl ketone and vinylpyridine. It would be quite wrong to give the impression that Dr.Lacey’s interests were principally in fine chem- icals. The heavy organic chemical industry and particularly processes for the production of chem- icals from petroleum were clearly fascinating him more and more. In 1959 after fourteen years with the Distillers Company Ltd. and its associated com- panies he joined British Petroleum Ltd. at the Research Centre at Sunbury and there he had a leading part in the establishment of the Chemicals Division of which he was appointed manager in 1963. It was whilst holding this appointment and with the prospect of new fields to conquer before him that he was stricken with the malady which was to bring about his death. That chemistry has suffered a great loss by his passing cannot be doubted.Yet chemistry is the richer for his having lived for as author of nearly a score of scientific papers and inventor of more than a score of processes which are the subjects of British Patents some of his lasting contributions to the science are there for all to see. DECEMBER 1964 433 The heartfelt sympathy of his many friends and one who as well as being a fine scientist loved the colleagues will go out to his widow and to his son arts his hobbies included classical music the study of and two daughters. They mourn a loving sympa- history and growing roses someone for whom no thetic and understanding husband and father some- words can be a substitute. J. T. MCCOMBIE. CARL NlEMANN 1908-1 964 THE sudden death of Carl Niemann on April 29th 1964 in Philadelphia brought to a very untimely end a brilliant career of research and service to education.Carl Niemann was born in St. Louis on July 6th 1908. He did his undergraduate and Ph.D. work at the University of Wisconsin. His thesis research was carried on with Karl Paul Link and was concerned with the chemistry of uronic acids. In 1935 he moved to the Rockefeller Institute and in collaboration with Max Bergmann began the work on proteins and enzymes which was to become his major scientific interest. In 1937 he spent a year as a Rockefeller Foundation Fellow at the University College Hospital Medical School in London and in 1938 joined the staff of the California Institute of Tech- nology where he was Professor of Organic Chem- istry at the time of his death.He spent several years during World War I1 with the National Defense Research Committee working on chemical identifica- tion of war gases and was awarded a Presidential Certificate of Merit for his contributions. In 1950 Niemann and his co-workers began an extraordinarily comprehensive study of the hydro- lysis of a-amino-acid derivatives under the catalytic influence of the enzyme a-chymotrypsin. This work is generally considered to be an exemplary model of experimental accuracy in a field not always noted for careful investigations. a-Chymotrypsin is one of the most intensively studied of the group of naturally occurring catalysts that are responsible for the hydrolysis of proteins in living organisms.Like other enzymes a-chymotrypsin demonstrates a remark- able selectivity among similarly constituted substrate materials. Niemann’s work was guided by the con- viction that the apparently whimsical action of the enzyme must be guided by systematic responses to variations in the structures of the substrates and that knowledge of the way in which structural changes affect the speed of the enzyme-catalysed reactions would lead to an understanding of the nature of the active portion of a-chymotrypsin and of how the enzyme exerts its catalytic effect. To this end he obtained quantitative data on the interaction of over 300 model compounds with the enzyme. Insight into the complex pattern of behaviour was achieved by consideration of the hypothesis that substrates may be bound by the enzyme prior to hydrolysis in a number of ways.Some of these bind- ing modes would be appropriate for consummation of the cleavage reaction; other orientations would not lead to cleavage. This concept of “wrong-way binding” is one of only two or three fundamentally new ideas about the nature of enzyme-substrate interaction to have appeared in the last sixty years. It provided an explanation for many observations which were previously difficult to rationalise in- cluding a complete lack of obvious correlation between how firmly substrates of varying structure are bound to the active site of the enzyme and the rates at which they are hydrolysed.The validity of the hypothesis is strongly supported by the fact that it becomes possible to predict the relative reactivities of many substrates by assuming that the affinities of different substituent groups on the substrate mole- cule for various interaction sites in the active centre of the enzyme are constant. Thus a certain group may be held particularly strongly by one of the “hands” of the enzyme. Depending on where in the substrate this group is located the preferred orientation of the molecule at the active centre may be a configuration favourable to hydrolysis or one in which hydrolysis is slow or even impossible. The progress of this research which was clearly Niemann’s principal scientific work was sum-marised excellently in an article in Science 1964,143 1287.He was elected to the National Academy of Sciences in 1952 and was Chairman of its Chemistry Section at the time of his death. He was a member of the American and British Chemical Societies and a fellow of the American and New York Academies of Science. He was for many years a member of the Editorial Board of Organic Reactions. He served the California Institute of Technology not only as pro- fessor but also as Chairman of the Faculty (1959) and Chairman of the Graduate Committee of the Divis- ion of Chemistry and Chemical Engineering. Carl Niemann was a scholar and scientist of the first rank and was as distinguished for his fine per- sonal qualities as for his intellectual achievements. He was generous thoughtful and understanding with a rare humour which was particularly effective in committee work for reducing arguments to their proper perspective.He leaves his wife Mary and two daughters Dorothy and Linda. JOHND. ROBERTS GEORGE S. IJ”D. PROCEEDINGS FREDERIC HORACE GARNER PROFESSOR HORACE FREDERIC GARNER,Emeritus Professor of Chemical Engineering in the University of Birmingham died suddenly at his home at Wymeswold Leicestershire on Saturday September 19th 1964 at the age of 71. Born of poor parents F. H. Garner was a dis- tinguished member of a remarkable family (one brother was Professor of Chemistry at Bristol Uni- versity and another became Chief Scientist to the Ministry of Supply). He was educated at Market Bosworth Grammar School and then at the Univer- sity of Birmingham where he held the 1851 Exhibi- tion Scholarship.He then went to the United States where he spent some time at the University of Pittsburgh and later was a Fellow of the Mellon Institute of Industrial Research where he obtained his Ph.D. in 1921 for work on petroleum compounds. He became Chief Chemist to the A.G.W.I. Petroleum Corporation (now the Esso Petroleum Company Ltd.) Fawley and was later Director of Research of the Esso European Laboratories from 1935 to 1942 when he was appointed as the first Professor of Chemical Engineering in the University of Birming- ham. It was here that his remarkable talents flowered and under his direction the department grew from a handful of students to become the largest in this country and to make a significant contribution to this country’s very urgent requirements for men trained in this particular field.Under him the depart- ment obtained a reputation for teaching and research second to none and he did much to establish this new technology as a respectable branch of engineering in its own right. His modest and unassuming per- sonality masked an intellect that possessed the rare ability of being as keen in the committee room as it was in the formation or analysis of scientific prob- lems and he had the rare distinction of being Dean of the Faculty of Science for two successive periods at a critical time in the university’s growth. He was awarded the O.B.E.and Medal of Free- dom Silver Palm (U.S.A.) for his work on the war- time application of petroleum and among his many professional activities was a past President of the Institute of Petroleum. He served on a number of government committees and was Chairman of the Water Pollution Research Board until 1961 and of the Fire Research Board until his death. His wide breadth of interests is illustrated by the fact that he was a foremost authority on English Delftware and the author of a notable monograph on this subject. His concern for education was not confined to his own institution for he was since its founding a member of the governing body of Loughborough College of Technology and for the past six months a member of the Academic Advisory Committee which is steering that institution to university status -a goal which he had done much to help achieve.He will be long remembered in many fields but above all perhaps as a teacher for which he had not only a natural talent but an ability to understand and communicate with young people. He always put his students’ interest first and once when he was asked why he had never married and had a family in order to pass on his remarkable inheritance he replied “My students are my family.” His devotion to his work and the loyalty of his staff and students were typical of everything he had done as was the secret delight he took in his affectionate nickname of “Fred.” By his death British technology has lost one of its most distinguished scholars and teachers and everyone who knew him or worked for him will feel a deep sense of personal loss.(The Times Publishing Company Ltd. 1964. All Rights Reserved. Reprinted by permission from The Times of September 22nd 1964.) ADDITIONS TO THE LIBRARY Trade associations and professional bodies of the United Kingdom. Compiled by Patricia Millard. 2nd edn.Pp. 330. David Fanning Associates. Letchworth. 1964. On physical adsorption. S. Ross and J. P. Olivier. Pp. 401. Interscience. New York. 1964. Gas analysis by gas chromatography. P. G. Jeffery and P. J. Kipping. Pp. 213. Pergamon. Oxford. 1964. Chemical kinetics of gas reactions. V. N. Kondrat’ev. (Translated from the Russian.) Pp. 812. Pergamon. Oxford. 1964. Advances in the kinetics of homogeneous gas reac- tion.Z. G. Szabo. (Translated from the German.) Pp. 277. Methuen. London. 1964. (Presented by the publisher.) Kinetics of precipitation. A. E. Nielsen. Pp. 151. Pergamon. Oxford. 1964. Newer methods of polymer characterization (Polymer Reviews-No. 6). Edited by B. Ke. Pp. 722. Interscience. New York. 1964. Structure elucidation of natural products by mass spectrometry. Vol. 1. H. Budzikiewicz C. Djerassi and D. H. Williams. Pp. 233. Holden-Day. SanFrancisco. 1964. Tetracyclic triterpenes. G. Ourisson P. Crabbe and 0. R. Rodig. (Chemistry of the Natural Products No. 1.) (Translated from the French and revised.) Pp. 237. Hermann. Huddersfield. 1964. Steroid drugs. Vol. 2-Index of biologically active steroids.N. Applezweig. Pp. 449. Holden-Day. San Francisco. 1964. (Presented by the publisher.) Unitized experiments in organic chemistry. R. Q. Brewster C. A. Vanderwerf and W. E. McEwan. 2nd end. Pp. 271. Van Nostrand. Princeton New Jersey. 1964. (Presented by the publisher.) Wheat chemistry and technology. Edited by I. Hlynka. (Association of Cereal Chemists Inc. Mono- graph Series Vol. 3.) Pp. 603. American Association of’ Cereal Chemists. St. Paul Minnesota. 1964. Proceedings of the 8th International Conference on Co-ordination Chemistry Vienna 1964. Edited by V. Gutmann. Pp. 449. Springer Vienna. 1964. NEW JOURNAL Progress in Boron Chemistry from 1964 Vol. I.
ISSN:0369-8718
DOI:10.1039/PS9640000385
出版商:RSC
年代:1964
数据来源: RSC
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