PROCEEDINGS OF THE CHEMICAL SOCIETY OCTOBER 1957 THE PLACE OF CHEMISTRY. III.* IN A PUBLIC SCHOOL By G. CROMPTON MASTER,WINCHESTER (SENIORSCIENCE COLLEGE) A HUNDRED years ago this subject could have For the next twenty years the two of them taught been dismissed in one short sentence. Chemistry in converted classrooms which gradually ac-had no place in a Public School. Classics reigned quired some resemblance to laboratories. A supreme. Mathematics had begun to win uncer- laboratory assistant an untrained boy who sur- tain acceptance. Progressive Headmasters some- vived to become ultimately the doyen of the times introduced a few popular science lectures. whole department was added in 1886. Today chemistry has a firmly established Very important people the first science place.How has that place been won? How is it masters because they were the pioneers and laid being exploited now? What does the future the foundations for the present structure. Con- hold? In attempting some tentative answers to sidered purely from the timetable standpoint these questions it must be emphasised that there they led leisurely lives. They delivered a few are wide variations between different Public lectures a week to groups of the school at large Schools. Generalisation is almost impossible. It lavishly and lovingly prepared these early lec- has therefore been thought simplest to give all tures often illustrated by numerous elaborate detailed references such as dates for one demonstrations. The rest of their teaching time particular school.was devoted to a group of enthusiasts a very We start then with a literary and classical small and individualistic band at first who stronghold whose cloistered calm is just begin- managed somehow to be excused other subjects ning to be faintly disturbed by the rapidly ex- to learn some serious science. panding scientific turmoil of the nineteenth Even more vital perhaps than actual teaching century. There is no sudden or systematically was the impact made on the very close com- planned incursion. In OUI selected school the first munities to which these pioneers were admitted scientist a physicist was appointed to the staff on probation. The days of the beggarly usher in 1875. He was followed by a chemist in 1883. were over by this time at least in the leading *Other articles in this series are as follows I Oxford Proceedings 1957 p.185; 11 Cambridge p. 190. 273 schools. The common room of the late nine- teenth century contained men of high scholar- ship of intellectual interests and habits many with a wide and liberal outlook for their period. The newcomers had to measure up to their standards in scholarship courtesy tolerance. Above all it was essential to avoid becoming figures of fun scholastic poor relations like the unhappy “drawing master” of a rather earlier age. They had to gain the respect if not yet the full understanding of men and boys steeped in the fine discipline and traditions of the classical humanities. Fortunately most of the early scientists proved equal to their task.The day of the scientist as housemaster had hardly dawned as yet. That was asking too much. Even his science was very much an outside subject a mere trimming to the main curriculum but by the turn of the century he was within his limits an established institution. The erection in 1903 of a building solely designed for the teaching of science ushered in the next stage in the story. No gimcrack makeshift this new building. The governors of the ancient foundation to which it was the latest addition were slow to move but they built for posterity. So sound and solid was the actual structure that its present occupants are now adapting it (not for the first time) to modern needs rather than destroy and rebuild.The two scientists for whom it was designed (there was still no biologist) were spaciously housed. The single chemist with whom we are particularly concerned had a good-sized lecture room a large laboratory a vast “preparation room” equal in area to the laboratory a balance room chemical store and washing-up room. The best material was used everywhere including lavish quantities of solid fully seasoned teak on which half a century of wear has inflicted only quite superficial injuries. Consolidation is often a slow process. Gradually an increasing number of boys were allowed to arrange their timetables to admit of some extra science. Examination requirements began to exercise a slight but growing effect. The appointment of a biology master in 1906 was probably necessitated in the first place by the needs of embryo medical students.It was not until 1921 however that boys ceased to be mere- ly seconded to science from their classical divisions and a definite science ladder was started. PROCEEDINGS Somewhat hesitant the school authorities about this new venture casting many doubtful glances backwards painfully over-anxious to avoid the least trace of “over-specialisation”. But the die was cast. The science department had come of age. Since then its history has been one of steady expansion in staff boys and buildings. At the moment partly with the help of a most generous grant from the Industrial Fund the buildings are to be further enlarged and fully modernised.As for staff and boys they have become regarded as completely normal members of the school community. Their special needs are recognised and provided. Most headmasters and bursars indeed would say that they receive in- evitably if inequitably something more than their fair share of the money available. The general problems involved in the actual teaching of chemistry are common to all schools handling pupils up to University entrance standard. Detailed conditions vary so widely in different schools that it is impossible to general- ise. If however we may stick to the facts for one particular school an old-established Public School with a high intellectual standard at which all boys are full-time boarders it is pos- sible to outline certain factors which are basic to the way in which the teaching of chemistry is organised.In the first place boys normally enter the school at 13 years old and practically all stay until they are 18. They pass an entrance examina- tion which ensures that their general intellectual standard is high but most of them arrive know- ing little or no science. When they leave the majority pass on to a University usually Oxford or Cambridge or to the equivalent. Boys enter the school at very varying levels a really good scholar starting almost halfway up. On the other hand promotion especially in the lower part of the school is freely allowed at the end of every term not merely once a year. A boy starting low down has the chance to catch up rapidly.At the same time there are no block promotions to waft the dimmer brethren painlessly along. Some indulgence is allowed to age and good intentions but a boy who fails too long to gain ground may eventually have to leave the school. The staff are highly qualified. Classes are small. Laboratory assistance is sufficient and efficient. Grants for laboratory maintenance are adequate. Prepara- tion hours are uniform for all with some allow- OCTOBER 1957 ance for age properly supervised and a good deal of solid work is done in them. There is also a thriving Chemistry Club. This functions out- side teaching hours and is of course voluntary. It enables the enthusiast to do a good deal of extra practical work beyond the syllabus and the beginner to see whether chemistry is really his line.Boys can only join the science ladder when they have attained a certain general level in the school. Partly owing to the pressure of Univer- sity entrance requirements this level is tending to fall so that boys reach the ladder younger. At present the average boy joins the ladder when he has been from one to two years in the school so that he has three or four years as a science specialist before he leaves. Owing to the very varying levels at which boys enter the school and the terminal promotions it is difficult to organise any really systematic science courses in the lowest classes. The result is that “specialists” and “non- specialists” have divided before they learn any serious chemistry and are taught quite separate- ly.There are of course special cases of belated transfers in both directions made possible by the general flexibility of a school with a generous staffing ratio. As far as the %on-specialist” is concerned the aim is to give him as much general scientific back- ground as time will allow and his often un- scientific temperament will permit. Such boys pursue a four year course at the moment of two periods a week. About one-third of this time is devoted to chemistry. How to utilise it to the best advantage is not at all an easy problem. Probably the ideal solution is to find a first-class teacher and give him plenty of latitude. The main con- siderations are that boys should be interested and should gain a respect for the chemist and some idea of the lines on which his mind works.No external examination is taken and how much chemical detail is actually learned is not very material. The ultimate aim for the “specialist” is to give him a thoroughly good grounding in the subject. Immediate aims inevitably focus to a consider- able extent on examinations especially now that University places are at a premium. This is not quite as bad as it sounds if the situation is intel- ligently handled by the teacher. Examination syllabuses merely define in a rough and ready way the ground which all have to cover in any case at this stage of their chemical education. Examination results measure the success achieved in covering it.It may well be argued that University entrance at the moment depends too much on this one factor but some system of selection is unavoidable and there could be much worse criteria. The backbone of the specialist teaching in chemistry is an integrated three-year course lead- ing to G.C.E. Advanced level or Scholarship level for the abler boy. Ordinary level is relatively unimportant and boys take it in their stride. A few boys take a fourth year to reach Scholarship level. A few leave without reaching Advanced level. The best scholars compete for Open awards at Oxford or Cambridge. The hours of actual class teaching of Chemistry are not numerous averaging only five periods a week during the three-year course. Boys aiming at Scholarship standard also receive a good deal of individual attention during their last few terms.For the rest results are achieved by a combination of small classes picked boys adequate preparation and so forth. What is the future for Chemistry in our Public School? It is now a well-established subject for which reasonably adequate provision is made. About one-third of the whole school pass up the science ladder all of whom learn a good deal of chemistry although only a fraction of these of course ultimately specialise in the subject. Will this number increase ? Will the science ladder ultimately engulf all or nearly all the school? Is it desirable that it should? All of us can hold our own opinions on these points. The reader as a professional chemist may agree with the shoe- maker that there is nothing like leather.In the writer’s opinion for what it is worth the science ladder already attracts pretty well all boys who have a really strong scientific bent. There are perhaps another one-third of the school who have definitely non-scientific temperaments. Of the remainder probably a fair proportion could be turned into scientists of sorts and some may have to be under the stress of national needs. Possibly half the school may ultimately go up the science ladder but not much more. In conclusion the writer would like to emphasise yet once more that no statement made above is intended or believed to apply to all Public Schools. Their independence is their most valued possession.Because of it they defy classification. Long may they continue to do so. In dealing with the position of Chemistry in schools the writers of the above and the following article have attempted among other things to con- trast the conditions which govern the position and the handling of the subject in different types of school. The particular Public School to which specific references are made lends itself perhaps particularly well to comparison with a Grammar School. This school is probably unusually fortunate in some PROCEEDINGS respects such as size of classes quality of human material and proportion of boys passing on to Uni- versities. It is fully realised that these factors do not operate so fully in all Public Schools.While bringing out this contrast in details the writers would like to emphasise also their funda- mental community of purpose. Much that is included in one or other article is common to both types of school but limited to one account to avoid repeti- tion. A good example is the importance of the Science Masters’ Association in and through which the underlying unity of all Science masters is maintained and expressed. G.C. E.H.C. THE PLACE OF CHEMISTRY. IV. IN THE GRAMMAR SCHOOL By E. H. COUL~ON (SENIORSCIENCE MASTER COUNTY BRAINTREE, HIGH SCHOOL ESSEX) FORthe purpose of this article the term “Gram- mar Schoo1”is taken to include all schools to which boys and girls are admitted at the age of eleven years and in which all pupils are expected to take the Ordinary Level examinations of the General Certificate of Education; a substantial proportion of them remaining to study for Advanced Level examinations.Some of these schools are old foundations but the majority have been opened within the last sixty years following the establishment of a State-controlled system of secondary education at the beginning of this century. Nearly all of them receive some form of financial aid from the Treasury and few now charge fees of any kind. In the nineteenth century the Grammar Schools were attended by the children of “middle class” parents; most of them left school at the age of sixteen to follow careers in commerce trade local and central government etc. With the Public Schools they aimed at producing men and women fitted to become leaders in indus- try and the professions knowledgeable in the arts and interested in the spiritual and material aspects of life as it affected them and their fellow citizens.In conformity with the educational theories of the time the curriculum in these schools was dominated by the study of the languages history and literature of the modern and ancient civilisations; in addition some mathematics and geography were taught. Formal instruction in chemistry began to appear in the Grammar Schools during the latter half of the last century. Owing to the expense in- volved in the provision of laboratories and equip- ment and to the scarcity of suitably qualified teachers progress was slow.The pupils derived much of their information from text-books illustrated on occasion with experiments per- formed by the teacher. This not very satisfactory state of affairs was transformed in 1884 by the zeal and enthusiasm of H. E. Armstrong. Arguing that science is something one does and not something one watches being done Arm-strong advocated the heuristic method of teach- ing chemistry. Pupils were to be put in the position of original observers and discover for themselves and by their own efforts the facts underlying scientific theories. If used as the sole basis for chemistry teaching this method has been shown to be impracticably slow but its effect has been considerable and lasting. In par- ticular it has led to the increasing recognition of the importance of individual practical work and of the need for the provision of laboratory accommodation for this purpose.Armstrong’s methods strengthened the claims of chemistry as a subject for the Grammar School curriculum and laboratories began to appear in many of the new schools opened in the early years of the present century. In general its serious study (with physics) was undertaken by boys only the OCTOBER 1957 girls’ schools inclining more to botany for their scientific needs. It is important to realise that this represented a limited advance only; the science subjects were merely grafted on to a pre-existing educational system. An event of major significance in the teaching of science in schools occurred in 1900 when a letter signed by four masters of Eton College was circulated to the science masters of 57 schools suggesting that a conference be held to discuss matters of mutual interest.This meeting was convened in January 1901 under the presidency of Sir Henry Roscoe and resulted in the foundation of the Association of Public School Science Masters. In 1919 membership of this body was extended to all graduate science masters in Grammar Schools the title being changed to the “Science Masters’ Association”. On the creation of a large number of new second- ary schools by the 1944 Education Act member- ship was further extended in 1946 to cover science masters in these schools. Concurrent with the expansion of the Science Masters’ Associa- tion has been that of the Association of Women Science Teachers which was formed in 19 12.The combined membership of the two associations now approaches 6,500. They are concerned with all aspects of science teaching in schools and maintain close contacts with the Universities industry the examining boards manufacturers of apparatus etc. There is a constant interchange of ideas between their members through the pages of the “School Science Review” and through meetings of the main associations and of their branches. Thus through the activities of these two organisations many of the decisions regarding the pattern and conditions of chem- istry teaching can be influenced by the men and women actively engaged in it.In this respect science subjects occupy a position which is in advance of that held by other subjects in the Grammar School curriculum. Outside the schools the Science Masters’ Association is perhaps best known for its initia- tion of what is often called the “General Science movement”. This was aimed at ensuring that no pupil leaving a Grammar School should be ignorant of the fundamental ideas of the major branches of natural science. The movement has excited a good deal of controversy into which it is not proposed to enter here but it is relevant to remark that not the least of its effects has been a marked increase in the amount of chemistry and physics studied by girls and of biology by boys. The content of the chemistry courses in Grammar Schools is dictated mainly by the syllabuses of the public examining boards and by the examination papers at Ordinary and Advanced Levels set on these syllabuses.It is not however true to say that these are matters outside the control of chemistry teachers. The syllabuses concerned have in the main been based on suggestions emanating from the Science Masters’ Association and their details have been settled by committees on which there often is and always should be a strong teacher representation. In the minds of all competent chemistry teachers there is no doubt that their subject can hold a place in the Grammar School curriculum by virtue of its cultural value. It is rich in examples of the power and scope of the human intellect and its great generalisations can match the highest achievements of mankind in any other department of learning.Examples of its applications touch almost every aspect of our daily existence and no one can be said to be fully educated if he is ignorant of these and of possible future advances in them. The national need for a marked increase in the output of technologists renders imperative the attraction of more boys and girls into science sixth forms whilst some appreciation of the fundamentals of chemistry is necessary for those pupils who leave school at sixteen to enter student apprenticeships or train as technicians. In considering the vocational aspect of chemistry teaching it should be remembered that a relatively small proportion of those who study it even as a specialist subject in advanced courses will become professional chemists; for many the work done in a Grammar School represents the whole of their formal education in this subject.Conditions for teaching chemistry vary in different Grammar Schools but not so widely as. in the Public Schools so that some generalisation is possible. The age of entry being two years lower than for a Public School courses can be spread over a longer time but the number of periods allotted to science subjects in the early years is often small and the relative immaturity of the pupils makes progress slow. In most schools the chemistry course is divided into three more or less clearly defined parts.The first of these occupying two or three years is introduc- tory and aims at inculcating habits of accurate observation simple deduction and precise re- cording together with some mastery of basic laboratory techniques. In this chemistry is often part of a General Science course and a modified heuristic approach is sometimes used in teaching it. The second stage again of two or three years ends at age sixteen or thereabouts and leads to the Ordinary Level examinations in which chemistry may be taken as a separate subject or as part of General Science or Physics-with-Chemistry. Finally the science specialists com- monly spend a further two years preparing for Advanced Level examinations in the sixth form. A third year of advanced work is sometimes undertaken by those seeking scholarships.Classes tend to be larger than those in the Public Schools it is not uncommon to find thirty-five or more pupils doing practical work together. There is some evidence that the staffing position is improving slowly but difficulties still arise especially in girls' schools. Arrangements for the provision of laboratory technicians vary from one authority to another; a good deal remains to be done before suitably trained assistance is available to all chemistry teachers. The courses outlined above are not taken by every pupil in a Grammar School. In many schools some degree of specialisation begins after the second or third year i.e. at age thirteen or fourteen and a proportion of the pupils ceases to study chemistry from then onwards.In spite of repeated attempts to persuade parents and pupils that a Grammar School education should extend over seven years large numbers of boys and girls leave at the age of sixteen and of those who remain many specialise in subjects other than the sciences. Under present conditions a significant proportion of the leaders in industry commerce and administration is drawn from men and women without specialist qualifications in science and attempts have been made in recent years to establish science courses for sixth-form pupils specialising in other disciplines. 'in these the sociological humanitarian and ghil-ossphial aspects of chemistry physics and PROCEEDINGS biology are stressed.The importance of such courses cannot be over-estimated but success with them demands teachers of outstanding ability. It is unfortunate that shortage of suitable staff hampers their development in many schools. Thus of the boys and girls entering the Grammar Schools almost all have some instruc- tion in chemistry for the first two or three years a fairly high proportion continue this for two or three years more and a quite small proportion for a further two years. In a predominantly scientific age these arrangements are plainly in- adequate but there is yet another side to the picture. For the first five years the place of chemistry is that of a junior partner in a cur- riculum which is still mainly devoted to language study.The total time available taken over these years for a chemistry teacher to prepare his pupils for the Ordinary Level examination rarely exceeds half that which is given to his colleagues teaching any one of the subjects French German Latin and mathematics despite the fact that the syllabuses for these are no more burdensome than those for the science subjects and of the necessity of giving much science teaching time to individual practical work. Cur- rent complaints in the press and in public state- ments by educationalists and others of the evils of over-specialisation which is usually inter- preted as too much science in sixth forms often neglect this important factor completely. A measure of specialist work in sixth forms is both proper and necessary having regard to the pressing need for more scientists and to the interests and aptitudes of young men and women.It is in the lower school that the curriculum is un- balanced and certainly it is not weighted towards the science subjects. The reason for this is evident-in many ways science is in the same position as it was during its infiltration into the Grammar School system fifty years ago. To meet present day requirements the curriculum especially that for the eleven to sixteen age group needs re-orientation so that chemistry is given at least parity with the so-called core subjects. The resulting increase in teaching time will per- mit greater emphasis on the contributions of the chemist to the prosperity of the world and to the welfare of its peoples.An ever-growing supply of fascinating material is becoming available for this purpose from industrial and other organisa- OCTOBER 1957 tions time considerations alone prevent chem-istry teachers from making the most effective use of it. Apart from its importance in the general education of the future citizen the interest aroused by the modernisation of syllabuses can play a vital part in attracting more boys and girls to careers in science and technology. The implementation of a programme of this kind will involve the provision of more laboratory accom-modation than many schools possess at present. The Ministry of Education must stimulate and encourage Local Education Authorities to match the speed and foresight of the Industrial Trust for the Advancement of Scientific Education.PEDLER LECTURE* The Course of Polar Reactions in Non-polar Conditions BYC. K. INGOLD COLLEGE STREET, (UNIVERSITY GOWER LONDON W.C.1) TODAY’S subject does not lend itself to the telling of a tidily finished story but I chose it because the Pedler Lecturer is definitely instructed to deal with some new departure opening up new opportunities. What has come to light about the course of polar reactions in non-polar conditions is recent and unexpected; it has about it the air of first experiences in a new adventure; and it is as unfinished as it is suggestive. I commence with the commonplace that over the last thirty years organic chemists have found that a major part of their subject depends on heterolytic reactions in which the electron-pair bonds are split and formed unsymmetrically.Such reactions are also called “polar reactions” a phrase which signi- fies that their transition states carry electric charges. These charges if free would be sources of great instability; but they are normally enabled to exist by what is called “solvation” that is by surrounding material which they polarise to form a largely neutralising sheath. The solvents which readily accept such polarisation that is those whose mole- cules can provide a good local concentration of neutralising fields are termed “polar solvents”. Thus most organic reactions are customarily con- ducted in solution and a considerable proportion of them in polar solvents.Now the extent to which a heterolytic reaction is polar is a matter of mechanism. Bimolecular nucleo- philic substitutions and eliminations SN2and E2 as we label them are normally not so polar as unimolecular substitutions and eliminations labelled S,l and El in which a molecule such as an alkyl halide must first be split into ions the final products being then derived from fast reactions of the car- bonium ion. Such unimolecular reactions are characteristic particularly of some secondary alkyl halides such as benzhydryl halides and of tertiary halides such as tert.-butyl and triphenylmethyl halides. The subject of this lecture grew out of the study of just these unimolecular reactions.They are highly polar reactions obviously favoured by polar con- ditions. At first that is in the 1930’s they were studied in those most highly polar solvents of all the hydroxylic solvents. That created a difficulty. Inevitably the solvent was the reagent the reactions as we say were solvolytic. Though one could often observe first- order kinetics or an approximation thereto that did not prove mechanism because the solvent concen- tration remained constant. Some more elaborate kinetic test of mechanism was needed. The methods which were introduced for this purpose were really variations of one general method the principle of which it is convenient at this point to explain. Essentially a controlled competition is set up.In solvolytic substitution we introduce a second substituting agent in controllable concentra- tion. It might be any of various things perhaps the lyate ion the anion of the solvent hydroxide or alkoxide; or it might be the so-called common ion the same halide ion as that derived from the alkyl halide; or it might be some reagent quite un-connected with the original system. Whatever it is the kinetic effect is judged on a basis which the following analogy will make clear. If two horses nibble the same haystack neither interferes with the meal of the other because there is plenty of hay- stack; but if the two are jointly hand-fed one straw at a time then what one gets the other must go without. In the first case the feeding rates are additive; in the second they are complementary.That is the whole principle. So for example when we examine the solvolysis of benzhydryl bromide in an aqueous medium with added azide ions as competitor (cf. Scheme l) the rates will tell us whether the water and azide ions are simultaneously attacking the “ haystack ” of plentifully available benzhydryl bromide moleculcs as in mechanism * Delivered before The Chemical Society at the Royal Institution London on February 14th and at the University Liverpool on February 27th 1957. SN2,or whether they are competing for the “straw- ration’’ of carbonium ions formed one at a time as in mechanism S,l. Actually the second alternative is correct; but we are concerned now only with the principle of the method.PROCEEDINGS it remained approximately constant. In Fig. 1 the initial specific rates of reaction of m-chlorobenz-hydryl chloride with three substituting agents are plotted against the concentrations of the latter. The somewhat small change of rate with concentration SCHEME I . Competitive diagmris of mfclianism. Example Aqueous solvolysis of Ph,Ci-IBr (N3-added 2s competitor). In S,2 imes me additive $-H,O --+ Ph,CH.OH -I-HBr Ph,CHBr { + N -} . . . s,2 + Ph2CH.N3 In S 1 rates are coniplementnry Ph,CHBr Ph,CH+ +-Br I Ph2CH+ Ph,CH*N, Fast -> During the 1930’s the conclusions reached by methods based on this principle won general accep- tance only slowly and it was because of this that the wish arose to carry the study of unimolecular sub- stitutions and eliminations out of the field of solvo-lysis by transferring them not indeed at first to non-polar solvents but at least to non-hydroxylic solvents so that the very simplest criterion of mechanism the kinetic form as might be expressed in reaction order could be applied.The selected solvent was sulphur dioxide which was chosen because although its dielectric constant is only 14 it was known to support ionisation in at least some alkyl halides. The results of these experiments contained some very puzzling features. One took a particular alkyl halide such as tert.-butyl bromide which readily undergoes elimination or benzhydryl chloride which undergoes substitution; and one followed the behaviour of the common substrate with a series of reagents-fluoride ion water pyridine triethyl- amine.One’s preconceptions were first that the kinetic form of the reactions should now be clearly different according as the mechanism was bimole- cular or mirxolecular; and secondly that the rates themselves should differ by factors of many thousands over that range of reagents if the mechanism were bimolecular but should be identical if it were unimolecular. In fact the observed kinetic forms agreed with and only with the unimolecular mechanism. But the observed rates instead of being identical were spread by moderate factors such as 3 4 or 5. And this was not due to just a little admixed bimolecular character because if it were the proportional spread of rates would shrink with diminishing reagent concentration whereas in fact J has been shown to be an activity effect in the fluoride reaction though that has not been proved in the other cases.But apart from such effects S,l curves should lie together horizontally; or if they have some ad- mixed SN2character they should radiate linearly from a common point. These curves do neither. It was concluded on the basis of somewhat general reasoning that they owe their peculiar form to long- range forces. 0.01 0.02 0.0.3 0-04 C FIG.1. Reactions of m-chlorobenzhydryl chloride with three substituting agents in sulphur dioxide at -10.75”. Initial specific rates (sec.-l )versus reagent concentration (M). That was three years ago; and I think still that the conclusion was right as far as it went.However no more detailed picture was developed of how the long-range forces do their work until unimolecular substitutions were carried into the completely non- polar solvent benzene. Limiting situations are often simpler than more general ones and probably the extreme situation in solvent benzene is simpler than the intermediate one in sulphur dioxide and is OCTOBER 1957 accordingly more amenable to analysis ; although as we shall see it is considerably less simple than the other extreme of hydroxylic solvents with which we started. The key to heterolytic reaction-mechanism in benzene is the great penetrating power of electro- static forces in that medium the dielectric constant of which is 2.25.The mass law of chemical kinetics depends on chance encounters of particles which for nearly the whole of their lives are out of each other’s force-range; “blind” encounters one might call them. That is usually taken for granted. But for strongly polar reactions in benzene that condition is not necessarily nor even very easily fulfilled. Consider first the simple case of ions. Two uni- valent counter-ions attract each other in benzene with an energy equal to the mean kinetic energy of either along a line at a separation of 500 A; they haul each other in from such distances. Fantastic as it sounds one could say in the language of collision theory that their “collision diameter” is 500a. Now the separations of solute neighbours at practical kinetic (or preparative) dilutions are only of the order of 50 A (or somewhat less).Clearly a system of ions at such dilutions would be a highly unstable already “collided” structure. Most of the ions would fall into pairs or other aggregates of shorter force-range. But even ion-pairs in benzene have a force-range a “collision diameter” (if we like to say so) which with polar reagents is of the order of magnitude of the spacings of solute neighbours at practical dilutions even the ion-pair state is incipiently “collided”. This has important kinetic consequences of which I will mention two. A reactive ion-pair newly produced in such a reagent system will not have to wait for a chance encounter as a condition for its reactions it will not have to wait until a reagent ion-pair or polar mole- cule in the course of its random Brownian wander- ings happens to come that way and hit it.The reagent is efectiveiy present from the outset it is within or not very clearly without the force-range. Contact then is not a matter of conventional kinetics that is a matter of chance as of a man with a black cat in a dark room :the lights are on and he can see the cat he can walk straight to it. In such circumstances access cannot delay reaction. If nevertheless the reaction of the freshly formed ion- pair is observed to be delayed then some other cause for this must be sought reagent access is not the cause and therefore an increase in the concen- tration of the reagent will not reduce the delay.Now it has hitherto been the single and exclusive conclusion from an observation of zeroth kinetic order in a reagent that that reagent is absent from 281 the transition state. However we now see another possible cause for such an observation namely that in practical conditions the reagent is ubiqui- tously present in the transition state. One can dis- tinguish between the two cases. When absence is the cause of a zeroth kinetic order then reactions of a common substrate with various reagents should have rates which are independent not only of the concentrations of the reagents but also of their identities; and in the past this supplementary criterion has always been satisfied.On the other hand when ubiquitous presence is the cause then the rates with each reagent will be independent of its concentration but characteristically dependent on its identity. A second consequence for polar reactions of the great force-range in benzene is found in the general phenomenon of electrostatic catalysis by interaction between a polar transition state and various ambient polar species. They may be molecules of some added polar but unreactive substance; or they may be molecules of the reagent in the reaction being studied -not the one that is reacting but other ones. Because of the great force-range these ambient entities can exert their kinetic effect in various num- bers and from various positions without being required to occupy specifically localised sites in the transition state.Naturally such catalysis will have no well-defined kinetic order in the catalyst. These are preliminary reflexions on what may be expected of polar reactions in benzene let us now consider some observations. Nucleophilic substitu- tions of triphenylmethyl chloride in benzene have been investigated by Hughes Pocker and some others with several anionic and also several mole- cular substituting agents. I want first to consider substitutions by two anions namely chloride ion (which must of course be isotopically distinguished) and azide ion. The first substitution is symmetrically reversible. The second is substantially irreversible. Both anions were supplied as their tetra-n-butyl- ammonium salts.It is necessary to be clear about the electrochemical conditions of such salts in benzene. At kinetically useful concentrations their equiva- lent conductances are of the order of mho cm.2 mole.-’. As concentration is raised from M or less to M or more the equivalent conductance at first falls and then rises the rising gradient at first steepening then slackening slightly and finally steepening markedly as shown in the logarithmic plot in Fig. 2. Fuoss and Kraus have previously obtained conductance curves of this general type for other salts in various solvents of low dielectric constant including benzene. The meaning is as follows. Throughout the con- centration range nearly all the salt is present as 282 ion-pairs.At lW5~,a few millionths of it are dis- sociated to simple ions which carry nearly all the current if they carried it all the slope of the plot would be -1/2. At M,simple ions are disappear- ing by adhering to the pairs and so triple ions are being formed again to the extent of a few millionths of the total salt. The triple ions are now carrying the greater part of the current if they carried it all the slope of the curve would be +1/2. But before this situation is reached they themselves are beginning -34 -36 -? -38 -40 -4 2 -5 -45 -4 -35 -3 -25 log c RG. 2. Equivalent conductances in benzene at 30". The broken lines have slopes of & 1/2. -3 1 /I I 1 -3 -2 -I /og[M+N;] FIG.4. First-order rate of reaction of triphenylmethyl chloride with tetrabutylammonium azide (M+N,-) in benzene at 30° logarithmically plotted against the con- centration of the salt.The straight lines show integral slopes. to be replaced by uncharged quadrupoles; and so near M the gradient slackens. Finally near M and beyond charged aggregates higher than quadrupoles become formed in increasing quantities. For most kinetic purposes the few millionths of the simpler charged species create no noticeable dis- turbance although some effects have been traced to them. However above M when high aggregates become plentiful and when also general electro- static catalysis by the ion-pairs becomes important PROCEEDINGS simple kinetics cannot be expected. Thus the most convenient region of concentration for simple and reasonably accurate kinetics is the millimolar region.In this region the rate of chloride exchange of triphenylrnethyl chloride with tetrabutylammonium chloride is independent of the concentration of tetrabutylammoniurn chloride. This is shown by the plot in Fig. 3 of the first-order rate-constant in triphenylmethyl chloride against the concentrations of the salt. In the same region of concentration the 04 O4 ' > J 4 ~x~o-~~ Edr] FIG. 3. First-order rate of chlorine exchange of tri-phenylmethyl chloride with tetrabutylammonium chloride in benzene plotted against the concentration of salt. -2 -3 -L' h -4 \ -5 I I -3 -2 -/ 0 log[Me 0H] FIG.5. First-order rate of methanolysis of triphenyl-methyl chloride in benzene at 25" logarithmically plotted against the concentration of methyl alcohol.The straight lines show integral slopes. rate of displacement of chlorine from triphenyl- methyl chloride by the azide group is independent of the concentration of the reagent tetrabutyl- ammonium azide. This salt unlike the chloride is freely soluble in benzene and so one can demon- strate the accelerative effects which appear at higher salt concentrations; and this is shown in the loga- rithmic plot in Fig. 4 of first-order rate versus salt concentration Except at low concentrations when the kinetic order in salt is zero there is no constant OCTOBER 1957 kinetic order in salt. In a plot of this kind the slope gives the order directly.Now the interesting thing is that these two zeroth- order rates in salt are not the same that for azide substitution is 5 times greater than that for chloride exchange. We saw in the experiments with sulphur dioxide as solvent the strong suggestion of a situa- tion of this kind. In benzene it is fully developed in dilute solution rate is quite independent of reagent concentration but is sensitively dependent on reagent identity. That must mean that the reagent is ubiquitously present in the transition state some differential delay in reaction is occurring after uptake of the reagent. The next step as always is to study competition. When we measure chloride exchange and add tetra- butylammonium azide the rate of chloride exchange falls.When we measure azide substitution and add tetrabutylammonium chloride the rate of azide sub- stitution falls. That is not the analogue of two horses eating a haystack. What is wanted by those reagents must be something in limited supply. That is to say a delay in reaction is occurring before uptake of the reagent. So we arrive at the picture of two slow steps with a fast step of reagent-uptake interposed between them. The first slow step is no doubt the familiar ionisation step of the S,l mechanism. But what is the second slow step? That is a question to which we shall return. First however we must pursue further this matter of competition. The forms of the competitive retardations are in- structive.When reaction with one salt is retarded by the addition of a second the loss of original rate is not equal to the rate of reaction with the second salt the total rate changes. The rule is that each salt in a mixture acts at a rate proportional to its mole-fraction just what this means is made clear with simple figures in Scheme 2. They represent relative first-order rates in triphenylmethyl chloride. At low concentrations none of the rates depends on salt concentration; but the rate with a mixture of salts depends on the composition of the mixture independently of its total concentration; and with an equiniolar salt mixture each salt reacts at half the rate at which it would react were the other salt absent. This means that although the two salts react at different rates they have equal competing powers.If it were not so if for instance the saline azide were more successful than the saline chloride in competing for a slowly supplied intermediate then an equivalent of the azide added to the chloride would cut the chlorine-exchange rate to less than one-half and an equivalent of the chloride added to the azide would not reduce the azide-substitution rate to as little as one-half. But not each rate is cut 283 by one-half. In round figures the rate ratio for the two reagents is 5 and the competing ratio is 1. SCHEME 2. Competition of Bu4N+Cl-and Bu4NfN3-for nucleophilic substitition in Ph,CCl. (Relative first-order rates in benzene.) Reagent Reaction with C1-N,-Bu,N+Cl-1-0.5 Bu4N+C1-+0.5 Bu4NfN3-0.5 2.5 Bu4N+N3-5 This confirms the three reaction steps.The rate reductions demonstrate the initial common slow step; the competing ratio of 1 is the ratio of the rates of the intermediate reagent-catching fast step ;and the observed rate ratio of 5 is the ratio of the rates of the second slow step-which are different for the different substitutions because the reagents have become involved by that time. We get further confirmation of the second slow step by the study of substitutions with molecular reagents as I will illustrate by just one example that of methanolysis. Many of the phenomena en-countered here are similar to those of the anion substitutions. Thus for methanolysis the logarithmic plot of the first-order rate in triphenylmethyl chlor- ide versus the methyl alcohol concentration is very like the corresponding plot for the azide substitution.It shows the reaction to be of zeroth order in methyl alcohol at low concentrations (Fig. 5). It also shows that at higher concentrations the rate rises and the order rises but without arrest at any particular value. This accelerative effect is interpreted as an electro- static catalysis. It can be qualitatively paralleled by adding unreactive polar substances such as nitro- methane. Then again the rate of methanolysis is depressed by added tetrabutylammonium chloride. This is an effect of competition it is indeed the now familiar common-ion effect of unimolecular substitutions S,l.It demonstrates the initial slow step. Its form shown in the logarithmic plot of Fig. 6 is consistent with this interpretation. However we encounter a new type of evidence of mechanism when we consider the catalysis of sub- stitutions by molecular reagents and particularly its contrasts with the catalysis of anion substitutions. The central point is that these contrasts are marked enough to show that the reactions each have an individually characteristic rate-controlling (and therefore catalysable) step in addition to the initial slow step which is common to them all. As an example we may consider the electrostatic catalysis by methyl alcohol of chloride exchange and of methanolysis. The rate comparisons are in Scheme 3. The basic rates of these two substitutions at low concentration are nearly the same.(That is coinci- dental with another alcohol they would not be.) If now we add O-lM-methyl alcohol we increase the chloride exchange rate by 140times but the methano- lysis rate by only 16 times. Thus the added alcohol diverts the primary reaction away from the sub- stitution in which it participates. That looks like “negative mass-action” and it would be absurd on any other basis than that the catalyst is operating after reagent participation has been fully determined. + Y 07 Ra.6. Logarithmic plot showing the depression pro-duced by added tetrabutylammonium chloride of the first-order rate of methanolysis of triphenylrnethyl chloride in benzene containing O-lM-rnethyl alcohol at 25”.SCHEME3. Discriminating catalysis. Relative first-order rates of reaction of Ph,CCl with Bu,N+Cl-and MeOH in benzene. For low concns. Cl exchange 1.0 Methanolysis 1.1 Add 0.1M-MeOH 140 17.5 (Note that extra MeOH diverts the primary reaction away from methanolysis.) The catalysis of molecular and anionic substitu- tions by salts shows specificity in just the opposite direction. The details which I omit are different; but the general conclusion is the same. I shall now take it that the examples given are sufficient to establish the form of the mechanism. It is not difficult to fill in the specific chemistry. This is done in Scheme 4.The first slow step is the basic step of all unimolecular heterolytic reactions in particular of S,l reactions; it is an ionisation; but because of the weak solvating power of the solvent the ions remain in contact as an ion-pair.The second step which is fast will be the pulling-in by the freshly formed alkyl halide ion-pair of a reagent PROCEEDINGS ion-pair or polar molecule a process which will begin at once,because the force-range is comparable to the neighbour distance and will take only the very short time (in general less than a microsecond) of a directed electrokinetic transport over a few tens of Angstroms this fast step is then one of dipole association and its product is a quadrupole. In order to discover the nature of the third step which is the second slow step consider the particular case of chloride exchange.Its mechanism must be exactly SCHEME 4. The S 1 mechanism in benzene SLOW-FasL TCl =T+Cl-(T+Cl-) (M+X-) Fast SLOW-Fask TX I-T+X-Y=== (T+X-)(M+Cl-) Fast Fast (For alcoholysis read H-OR for M+X-.) symmetrical about some central point. No symmetry has entered so far into our description and so the only possible central point is the transition state of the second slow step. Therefore this step itself must be symmetrical and since its factor is a quadrupole its product must be a quadrupole in short the second slow step is one of quadrupole rearrange- ment. It is formulated not for chloride exchange alone but for the more general case of substitution in an alkyl chloride. We have to consider why quadrupole rearrange- ment is a slow process.Simple electrostatic theory shows that dipole association is lateral if dipoles are long and thin but longitudinal if they are short and thick. A calculation based on models shows that with the triphenylmethyl chloride ion-pair as one component dipole the most stable quadrupoles are those formed by longitudinal association as repre- sented in Scheme 4. This first-formed quadrupole has to wrap its “tail” round its “head” in order to pass into that stereoisomer which alone can dis-sociate to give the products. This process is depicted in more detail in Scheme 5. The important point is that this rearrangement cannot be accomplished without some temporary loosening of the charges. In the transition state (enclosed) there is a nett loosening of unlike charge pairs.The re uired loosenings are small in distance (a very few xngstroms) but are substantial in energy as may be shown by a thumb-nail calculation. Thus with a dielectric constant of 2.25 the work of separating one pair of charge centres say from 4 A to 5 8 is 7.4 kcal. /mole. Although there will be some compensation among the six energy terms OCTOBER 1957 four of them positive and two negative which have to be computed in an electrostatic calculation of the activation energy it will be obvious from this simple example that the activation energy of the rearrange- ment may be of the order of magnitude of 10 kcal./ mole and hence could be a major component of the overall activation energy.SCHEME 5. The quadrupole rearrangement. I+ I A schematic energy diagram of the mechanism is given in Fig. 7 for the example of the symmetrical reaction of chloride exchange. It shows the two steps (ascending to the transition state) of rate control and the interposed fast step (descending) of reagent capture. Electrostatic calculations based on models gave the exothermicity of quadrupole formation as 6 kcal./mole and the activation energy of quad-rupole rearrangement as 10 kcal./mole. I have set the endothermicity of the primary ionisation equal to 12 kcal./mole in order that it shall in combination with the calculated figures give the observed over- all activation energy of 16 kcal./mole. That is all I have to say about benzene as a sol- vent except to observe that whilst it is a non-polar solvent it is not completely non-solvating because its molecules though non-polar are polarisable.If one wants to go to the limit in exploring the extent to which polar mechanisms maintain themselves in conditions of progressively reduced solvation one has no need to stop at solvent benzene one can go to that best of all non-solvating “solvents” the per- fect vacuum. We are thus led to consider how far this question has been pursued in the field of gas reactions. This field has long been regarded as a private preserve for homolytic reactions. The usual defence of it against heterolytic invasion is in a familiar form -the form used in the field of solution chemistry against Arrhenius in the 189O’s and to come nearer home against some organic chemists in the 1930’s heterolysis it was said and it is now said of gases is energetically inadmissible.Nevertheless Maccoll and his associates are prepared to assume it they have indeed invaded this last homolytic stronghold by proclaiming heterolytic unimolecular gas reactions. The reaction they have studied is unimolecular elimination. There is some evidence of the existence of a large family of analogous olefin-forming gas- reactions including dehydrohalogenations of alkyl halides elimination of acid from esters dehydrations of alcohols and deaminations of mines. The main investigations so far have been on the dehydrohalo- genations of alkyl bromides and chlorides.Before one can investigate a molecular gas reaction as of an alkyl bromide a considerable technique has to be pursued. One must suppress surface reactions. One must also prevent chain mechanisms from blowing up by their multiplying power to an observable size those side-reactions of homolytic character which as primary processes are of no Reaction step FIG.7. Schematic energy diagram for an S,l reaction in benzene in the example of chlorine exchange between triphenylmethyl chloride and tetrabutylammonium chloride. relative significance. Then one can isolate a mole-cular gas reaction. That of alkyl bromides and chlorides proves to be unimolecular. The evidence that it is heterolytic comes from observed structural effects on the rate.If in ethyl bromide as parent successive methyl groups are introduced so as to make the CBr and CH centres primary secondary and tertiary independently relative rates of dehydrobromination are found which are shown as in Scheme 6. Rate is almost wholly determined by the immediate environment of the CBr centre. The effect of the groups flanking the CH centre is relatively so trivial that is is hard to say whether it is really exerted there or after relay at the CBr centre. SCHEME 6. Unimolecular elimination in the gas phase. R R \/ C-C with R =H or Me; relative /I1\first-order rates at 380”. R HBrR CBr prim. primary1 secondary170 380 tertiary32,000 46,000 tert. 6.3 - 130,000 An analysis by means of the Arrhenius equation shows that the frequency factors of all these reactions are nearly the same they are grouped around 1013 the "theoretical" value for unimolecular reactions.The rate differences thus arise essentially from dif- ferences of activation energy. The activation energies for dehydrobromination of ethyl isopropyl and tert.-butyl bromide and for dehydrochlorination of the corresponding chlorides (the latter figures being due to Barton and Howlett) are shown in Scheme 7 SCHEME 7. Activation energies of elimination com- pared with energies of homolytic and heterolytic dissociation (kcal./mole) EtBr Pr'Br ButBr Arrhenius E 53-9 47.8 42.2 D(R+Br)D(R++Br) 67.2 183-7 67.6 156.3 63.8 140-3 EtCl PriCl ButCl Arrhenius E 60.2 50.5 41.4 D(R+Br)D(R++Br-) 80.9 192.8 82.2 166.3 78.3 150.2 where they are compared with two sets of dissocia- tion energies.It will be seen that the activation energies bear no relation to the energies of homo-lytic dissociation of the bonded halogen which change only slightly and indeed go through flat maxima in the alkyl series. The activation energies do however vary similarly to the heterolytic dis- sociation energies for dehydrobromination the former are just 30% of the latter. CH3. CHCl. CH3 1013*40 exp (-50,5W/RT) 1 1 1 CH,.CHCI.CH 1 CH,Cl.CH 1 So we arrive at a picture of a rate-contmlling step involving halogen heterolysis but no hydrogen loosening of any kind. This picture is supported by several special observations of which we may notice two both by P.J. Thomas. One is that the rates of reaction of 2-bromobutane and 4-bromopent-1 -ene are practically the same even though in the latter PROCEEDINGS an allylic hydrogen atom is to be removed and a conjugated diene is to be formed. The data are in Scheme 8. This shows clearly that neither hydrogen loosening nor double-bond formation is making aw progress whatever in the rate-controlling step. The other observation is that an a-methoxy-group has an enormous accelerating effect on the gas reaction reducing the temperature of convenient observation by nearly 200". The rate data are in Scheme 9. The substitution of methoxyl for methyl SCHEME 8. 1 CH3.CH.CH.CH3 CH2 :C;I.CH.T.CH H Br H Br I I 5-5-CH3.CH:CH.CH3 I CH,:CH.CH :CH.CH Rates (sec.-l) (-46,500/RT) I 1C?2*94exp 1013*53e~p (-4-4,700/RT) Relative rates (380") 1-00 I 1.05 increases rate by lo6 times at 200" or by about 10l2 as calculated for 0"c.The latter factor is almost the same as the best estimates we can make of the factors by which the replacement of a-methyl by methoxyl increases the rates of the unimolecular solvolytic substitutions of the chlorides in hydroxylic solvents at 0". In Scheme 9 an estimated factor is given for CH,.CHCl.O.CH exp (-33,00O/RT) sec.-l 105.9 at 200" 1of'.6 at 0" CH,.CHCl. 0.CH, -loll to 1012 at 0" CH2Cl.0.CH3 -1013 at 0" the same pair of chlorides and also one for their lower homologues. The data point strongly to a common interpretation and for solvolysis the accepted interpretation is that of the electromeric effect of methoxyl on halogen ionisation C H3-3-C-'E 1 OCTOBER 1957 It is difficult to contemplate these results without concluding that a heterolytic El mechanism is being observed which is based on ionisation in the gas phase though not of course on ionic dissociation.This mechanism is formulated in Scheme 10. Except SCHEME 10. A heterolytic unimolecular gas reaction. The unimolecular elimination mechanism El. that the ions do not fall apart it is the same as the El mechanism in polar solvents. I do not myself worry about the energy “bogey”. I think that of the 184 kcals. said to be required ionically to dissociate a mole of ethyl bromide probably more than 100 kcals.perhaps as much as 120 kcal. is needed to separate the formed ions which have not to be separated in the rate-controlling step formulated. Moreover the pair of ions will surely lose a further few unreckoned tens of kilocals. in mutual polarisa- tion-perhaps with some transference of electrostatic binding to the point (represented by the brace in Scheme 10) at which reaction is going to be con- tinued (though this is not essential to the El scheme). It might be possible thus to account for the observed activation energy of 54 kcal./mole; or it might not. But it is a lesson of history that whenever a simple- minded conclusion in favour of heterolysis as the obvious deduction from plain chemical facts has been opposed with the assertion that the energy is unavailable the answer (in the past) has always been that some energy term has been forgotten.If these conclusions are at all correct heterolysis must come in a major way-just how major will have to be found out-into gas reactions and a fortiori into reactions in non-polar and weakly polar solvents. The three groups of experiments I have surveyed those in sulphur dioxide in benzene and in the gas phase are obviously only starting points in the explorations of polar reaction in a wide range of conditions including those which would formerly have been regarded as most unpromising indeed absurd to contemplate for reactions dependent on primary ionisation.So open is the field ahead of each of these starting points that it seems hardly possible to do a short set of experiments without disclosing something new and significant. That at least has been the recent experience of all those I know who have been exploring this field. References (A) To S,1 and El reactions in SO,. Bateman Hughes and Ingold J. 1940 1011 1017; Bird Hughes and Ingold J. 1954 634; Bunton Greenstreet Hughes and Ingold J. 1954 642 647. (B) To &l reactions in C,H,. Hughes Ingold Patai and Pocker J. 1957 1206 1230 1256; Hughes Ingold Mok and Pocker J. 1957 1238; idem and Patai J. 1957 1220 1265. (C) To El reactions in gas phase. Maccoll and Thomas J. 1955 979 2445; 1957 in the press; Nature 1955 176,392; Thomas J.1957 in the press; Harden and Maccoll J. 1955 2454; 1957 in the press also un- published work; Harden J. 1957 in the press; Kale Maccoll and Thomas unpublished work. COMMUNICATIONS The Photoisomerisation of Benzene to Fulvene By J. MCDONALD BLAIRand D. BRYCE-SMITH (CHEMISTRY THEUNIVERSITY, DEPARTMENT READING) NORMAN and PORTER^ refer to numerous statements in the literature that benzene is stable towards ultra- violet radiation. There is however evidence of some change when an organic glass such as E.P.A. (a mix- ture of ether isopentane and ethanol) containing benzene is irradiated at the boiling point of nitrogen. Thus Ingram Hodgson Parker and Rees,2 using paramagnetic-resonance technique found evidence for the formation of “trapped” free radicals in the glasses.Gibson Blake and Kalm3 found absorption maxima in the spectrum of the melted glass which despite a 7.5 mp displacement from previously re- ported positions they attributed to the presence of hexa-1 :3 :5-triene. Norman and Porter1 reported that similar maxima are found in the spectrum of the melted glass. We have found that the irradiation of pure benzene under nitrogen at 50” produces a small proportion of the yellow isomeric hydrocarbon fulvene. We believe that this represents the first example of the direct isomerisation of an aromatic to a non-aromatic hydrocarbon. The apparatus which will be described more fully elsewhere was designed to allow a high proportion of the radiation from an “Hanovia” S-500mercury-vapour lamp to enter a fused-quartz cell containing Norman and Porter Proc.Roy. Soc. 1955 A 230,339. Ingram Hodgson Parker and Rees,Nature 1955 176,1227. Gibson Blake and Kalm J. Chem. Phys. 1953 21 10o0. benzene. The inner quartz surface was rubbed mechanically with glass wool in order to prevent the deposition of polymer films. Irradiation for 2 hr. gave a fulvene concentration of ca. 0.1 g./l. a figure not surprising in view of the obviously high endo-themicity of the reaction. This proportion of fulvene was sufficient to impart a distinct yellow colour to the benzene. The fulvene co-distilled with the benzene through a column of ca. 10 plates but a five-fold concentration was readily effected by fractional freezing.A higher-boiling yellow oil probably fd-vene polymers was also always obtained. Fulvene was identified by a comparison of its absorption spectrum and certain chemical properties with those of an authentic specimen prepared in dilute solution from cyclopentadiene and formalde- hyde by a modification of Thiele's method and also by comparison with Thiec and Wiemann's spectral data.5 The characteristic peaks at 242 and ca. 365 mp were observed. The latter peak is rather flat and moves as the fulvene polymerises its tailing into the visible is responsible for the yellow colour. Thiec and /E~~~ Wiemann5 found E ~ ~ =~ 51.3 for freshly dis- tilled material and ~242/~362.= 45-7 for material stored at -70" for three days in an inert atmosphere.We obtained values of ~2421~365 = 48.3 51.2 and PROCEEDINGS 48.4. There was no spectral evidence for the forma- tion of hexa-l :3-dien-5-yne6 or hexa-l :5-dien-3-yn8 (the open-chain isomers) and none for hexa-1 :3 :5-triene.' These hydrocarbons are colourless. The in- stability of fulvene coupled with the difficulty of separating it from benzene have so far prevented our examination of the infrared spectrum. The present isomerised material was strongly un- saturated towards bromine in carbon tetrachloride and towards aqueous potassium permanganate. It was rapidly decolorised when warmed with maleic anhydride. It was instantly decolorised by piperidine and diethylamine and more slowly by methylamine benzylamine or alcoholic sodium hydroxide but was unaffected by trietliylamine pyridine aniline or mono- or di-methylaniline except after several days.The colour was not discharged by ammoniacal cuprous chloride. Closely parallel results were ob- tained with the solution of authentic material. Preliminary experiments indicate that benzene homologues undergo a similar rearrangement. The authors thank Professor E. A. Guggenheim, F.R.S. for helpful comments on the manuscript. One of them (J.M.B.) thanks Messrs. Hanovia for w grant. [Received September 9th 1957.1 Thiele Ber. 1900 33 672; Thiele and Balhorn Annalen 1906 348,1. Thiec and Wiemann Bull. SOC.chim. France 1956 177. Georgieff Cave and Blaikie J Amer. Chem. Soc. 1954 76 5494. 'I Woods and Schwartzman ibid. 1948 70 3394.The Use of Hydrazine Salts and the Influence of Catalysts in the Preparation of Borazole Derivatives By H. J. EMEL~~US and G. J. VIDELA CHEMICAL CAMBRIDGE) (UNIVERSITY LABORATORY IN experiments on the preparation of alkylated and halogenated borazoles we found that in Brown and Laubengayer's methodl for the preparation of BBB-trichloroborazole from ammonium chloride and boron trichloride at elevated temperatures the use of very pure ammonium chloride resulted in low yields. Cruder materials on the other hand which contained iron salts as the chief impurity gave better results. Then it was found that a mixture of pure ammonium salts with a catalyst consisting of metallic iron nickel or cobalt supported on pumice gave complete reaction with boron trichloride below 120" and with a yield of 50-60%.Further reaction of boron trichloride and methylamine hydrochloride occurred below 180" with the catalyst and again the yield was of the order of 60%. In the catalysed re- action much smaller quantities of non-volatile products resulted. Improved yields of borazole have also been obtained by using hydrazine hydrochloride OF aIkylated hydrazine hydrochlorides in place of am-monium or amine salts. In these instances also the catalyst may be used to lower the reaction tempera- ture and to improve yields. With hydrazine hydro- bromide for example the following reaction oc-curred below 200" with t,he catalyst 9N2H,,2HBr + 12BBr --+ 4B3N3H3Br3+ 42HBr + 3N It gave a yield of 4045% of purified B3N3H3Br3.The quantity of catalyst normally employed was of the order of 10% by weight of the salt and it was prepared by calcining the nitrate on powdered pumice and reducing the resulting oxide with hydrogen. The catalyst and the salt were then thoroughly mixed in a dry-box. IR the course of the reaction the catalyst was transformed at least super- ficially into halide. (Received August 19th 1957.) Brown and Laubagayer J. Amer. Chem. Soc. 1955,77,3699. OCTOBER 1957 289 Reactions of Acyl isoThiocyanates in Aqueous Solution By D. T. ELMORE and J. R. OGLE (STAVELEY LABORATORIES SHEFFELD, RESEARCH THEUNIVERSITY 10) INcontinuation of earlier work,l and as a variation of Edman’s method2 of stepwise degradation of peptides from the N-terminus we have examined the reaction of benzoyl isothiocyanate with amino-acids and peptides in aqueous dioxan at alkaline pH.The reactions of acyl isothiocyanates are complex since addition to the .N :C :S system and nucleophilic sub- stitution at the carbonyl-carbon atom may compete with one an~ther.~ The rates of these reactions depend on factors such as basic strength of nucleo- philic reagent solvent polarity structure of acyl isothiocyanate and temperature. No kinetic investi- gations of the reactions of acyl isothiocyanates have been reported but qualitative results indicate that aroyl isothiocyanates normally react by addition; there are only isolated instances in the literature of benzoylation by benzoyl is~thiocyanate?~~ Benzoyl isothiocyanate reacts with water to give ben~amide,~,~ presumably through the intermediate N-benzoylthioncarbamic acid whereas N-sodium hydroxide liberates thiocyanate ion almost quanti- tati~ely.~ We have found that reaction of benzoyl isothiocyanate in aqueous dioxan at pH 8.5 and pH 6.3 (pH-stat7) followed by acidification affords a mixture of benzamide dibenzamide and a little benzoic acid.We formulate the reactions in the expression OH-H+ BzNCS +Bz.NH.CS.0--+ Bz-NH + COS 420H-4BzNCS BzO-+ NCS-Bz*NH*CS-OBz+ NCS--1-H,O 4 Bz,NH + COS Although these reactions were quite fast they did not seriously compete with those involving amino- acids and peptides the results of which are tabulated.A nucleophilic substitution involving benzoyl isothiocyanate and an amine should be favoured (i) in a highly polar solvent such as water and (ii) by using an amine of high pK, providing that it is partly dissociated at the pH of the reaction. Our results as well as experiments recorded by Dixon and Tayl~r,~ indicate that both factors must be operative for benzoylation to occur. Thus for exam- ple no N-cyclohexylbenzamide was detected when benzoyl isothiocyanate and cyclohexylamine inter- nctcd in benzene but in aqueous dioxan at pH 8.5 N-Benzoyl N-Benzoyl-Reactant pH compound thiocarbamoyl (%I compound ( %I Glycine 8.5 84 0 oc-Alanine 8.5 90 0 /3-Alanine 9.5 78 0 y-Aminobutyric 8.5 17 0 acid 6-Aminohexanoic 8.5 49 5 acid Norleucine 8-5 73 0 Glycylglycine 7.0 76 7 p-Aminobenzoic 8.5 0 -100 acid Anthranilic acid 8.5 0 -100 N-Phenylglycine 8.5 0 -100 cycZoHexylamine 8.5 21 53 , (inbenzene) -0 76 21 % was isolated.Further anthranilic acid p-aminobenzoic acid and N-phenylglycine which are weak bases reacted in aqueous dioxan exclus- ively by addition. Experiments with 6-aminohexanoic acid and glycylglycine indicated that addition to benzoyl isothiocyanate in aqueous systems became noticeable as the distance between the amino- and the carboxylate groups increased. It is clear that benzoyl isothiocyanate is an un- suitable reagent for procuring the stepwise degrada- tion of peptides through their N-benzoylthiocarb- amoyl derivatives.We have found however that 2 :4 :6-tribromobenzoyl isothiocyanate affords about 80 of the N-2 :4:6-tribromobenzoylthiocarbamoyl derivativesof glycine and glycylglycine after reaction in aqueous acetonitrile. Presumably acylation is sterically hindered by the ortho-substituents a phenomenon already observeda for the methanolysis of 2 :4:6-tribromobenzoyl chloride. The foregoing results although only qualitative demonstrate the deficiencies in our knowledge of the mechanisms of reactions of acyl isothiocyanates and we hope that other workers may be thus stimulated to carry out kinetic studies in this field. The authors thank Imperial Chemical Industries Limited for financial assistance. (Received August 15th 1957.) Edman Actu Chem.Scad 1950. 6. 283. ’ Elrnore and Toseland J. 1954 4533; 1957 2460. ,I Elmore Ogle Fletcher and Toseland J. 1956 4458 and references cited therein. Wheeler Amiw. Chem. J. 1901 26 345; Hoggarth J. 1949 1160. Dixon and Taylor J. 1908 93 684. Miqael Ann. Chim. Plzys. 1877 10 289. # Jacobsen and LConis Compt. rend. Trav. Lab. Carlsberg 1951 27,333. * Norris and Young J. Amer. Cliem. Soc. 1935 57 1420. PROCEEDINGS The Structure of cycloEucaleno1 By J. S. G. Cox F. E. KING,and T. J. KING (THE UNIVERSITY, NOTTINGHAM) THEprevious publication on cycloeucalenoll pre- sented evidence that this compound belongs to the tetracyclic triterpene series and in particular that it contains amethylene group next to an isopropyl group a cyclupropane ring and a 3p-hydroxy-group.The compound shows marked analogies to cycloartanol (I; R = R’ = Me R” = H,) but it was established that replacement of the methylene group of cyclo-eucalenol by hydrogen did not give cycluartanol. J Further work now enables us to allot an unam- biguous structure to cyclueucalenol namely 4~-demethyl-24-methylenecycZoartanol (I;R = Me R‘ = H R” = CHa. cycloEucaleno1 is thus the first known natural product containing a dimethyl- ated steroid nucleus in contrast with the commonly occurring trimethyl steroids (tetracyclic triterpenes). The first indication that cycloeucalenol had an abnormal A ring was obtained when the action of phosphorus pentachloride afforded a stable chloro- compound without rearrangement instead of the expected ring-contracted product.This seemed almost conclusive evidence for the lack of a gem-dimethyl group from position 4. The structure with no 4-methyl group (Le. I; R = R’ = H R” = CHa could not represent cyclo-eucalenol because the derived demethylhydroxy- eucalenedione was not identical with 3p-hydroxy- 14-methylcholest-8-ene-7: 1 1 -dione2 (11). There re-mained a possibility that C(4)carried one methyl group only and this was supported by molecular- weight determinations which favoured C3, for cycloeucalenol. Accordingly 24-demethylcyclu-eucalanone prepared by oxidation of the corres-ponding alcohol was methylated by the process developed by Woodward et al.2b and used in the cholestanone series by Beton Halsall Jones and Phillip~.~The required intermediate (111; side chain as in I; R” = Ha was readily obtained and methylation gave only one new product.This was reduced by Raney nickel and after re-oxidation afforded cycloartanone identified by m.p. mixed m.p. and optical rotation. We are indebted to Professor F. S. Spring F.R.S. for the mixed m.p. determination. This proof that 24-demethylcyclu-eucalanol was a 4-demethylcycloartanol together with the stability towards alkali of the dithian (Ill) which indicated the equatorial confirmation of the 4-substituent3 decisively establishes the structure (I; R = Me R’ = H R” = CH,) for cycloeucalenol. (Received August 29th 1957.) Cox King and King J. 1956 1384. 2 (a) Barton Ives Kelly Woodward and Patchett Chem.and Ind. 1954 605; (b) Woodward Patchett Barton Ives and Kelly J. 1957 1131. Beton Halsall Jones and Phillips J. 1957 753. The Hydrolysis of Methylated Deoxyguanylic Acid at pH 7 to Yield 7-Metbylguanine By P. D. LAWLEY (CHESTER BEATTY INSTITUTE INSTITUTE OF CANCER RESEARCH RESEARCH ROYALCANCER LONDON S.W.3) HOSPITAL THEquestion of the relative reactivities of groups in possibilities alkylation of ring-nitrogen atoms could the purine and pyrimidine moieties of nucleic acids occur,1 and further that it might not be necessary as towards alkylating agents remains unresolved in so previously assumed for a hydrogen atom directly far as products have not been isolated and identified attached to ring-nitrogen atom to be replaced.2 although it has been suggested that among other More recently it has been shown that guanylic Press and Butler J.1952 626. 2 Wheeler Morrow and Skipper Arch. Biocltem. Biophys. 1955 57 133. OCTOBER 1957 29 1 acid methylated at pH 7 yields 7-methylguanine on acid hydr~lysis.~ Further work outlined here has rz led to chromatographic isolation of a methylated deoxyguanylic acid which yields 7-methylguanine 70 on hydrolysis under much milder conditions than 8 for the guanylic acid product hydrolysis being appre- 4 ciable at pH 7 and 37". I6 Neutralized deoxyguanosine 5'-phosphate (0.1M) 9 was treated with dimethyl sulphate (1 mol.) in 0.4~- phosphate buffer maintaining the pH near 7.2 at 37" for 1 hr. The mixture chromatographed on Whatman No.4 paper with saturated aqueous ammonium sulphate-propan-2-ol-O*l~-phosphate (79 :2 :19)4at pH 7-2 as solvent afforded two components one of R 0.4 (as for unchanged deoxyguanylic acid) and the other of R,0.65 and with absorption maxima at 282.5 and 256 mp at pH 7. At 37" in buffer of initial pH 7.14 the latter product changed slowly into another giving the absorption spectrum of 7-methyl-guanine the half-life being ca. 20 hr. and the final pH 6.95. At 22" a precipitate was gradually formed in the original reaction mixture which unlike the original product gave no reaction for deo~ypentose.~ This precipitate recrystallised from water as colour- less needles (Found C 44.1 ; H 4.3; N 41.7. Calc. for C,H,0N5 C 43-6; €3 4.2; N 42.4%) and its ultraviolet absorption spectra at various pH's were identical with those of 7-methylguanine (see Figure).6 (These spectra show five isosbestic points resembling those presented by Weissmann et a1.' rather than those due to Gulland and Story,8 in which only three isosbestic points occur although the extinction co- efficients are of similar magnitude.) It appears there- fore that unless a rearrangement accompanies its hydrolysis the initial product is 7-rnethyldeoxy-guanosinium 5'-phosphate (I or the isomer with the charge on N(9$ From its conversion into 7-methyl- guanine followed spectroscopically it was deduced that its values of Emax.are 7800 (282.5 mp) and 9800 (256 mp) and hence that the yield was 60%. A mechanism is therefore established by which alkylation of guanine moieties of deoxyribonucleic acid could cause not only rather extensive changes in physicochemical characteristics due to quaternary Lawley and Wallick Chem.and Ind. 1957 633. Markham and Smith Biochem. J. 1951 49 401. Edward and Waldron J. 1952 3631. Fischer Ber. 1897 30 2400. 4 2 0 220 240 26U 280 300 320 Wavelength (mp) Product from hydrolysis of methylated deoxyguanylic acids x pH 12; + pH 7; 0,pH 1.3. Lines are for 7-methyl-guanine at the same pH's. groups at ring-nitrogen atoms but also elimination of the alkylated guanine moieties from the macro- molecule at physiological pH by the slower sub-sequent hydrolysis of the 7-alkylguanine-deoxy-riboside linkage. Further the latter process might be expected to facilitate fission of the polymer chain as suggestedg for the analogous case of the apurinic acids.The authentic sample of 7-methylguanine was a preparation by Dr. N. Anand obtained through the courtesy of Dr. D. M. Brown and Professor F. Bergel whom the author thanks. The helpful interest of Dr. E. M. F. Roe and Mr. G. M. Timmis is also much appreciated. [Received July 23rd 1957.1 Weissmann Bromberg and Gutman Proc. SOC.Exp. Biol. Med. 1954 87 257. Gulland and Story J. 1938 692. Brown and Todd in Chargaff and Davidson "The Nucleic Acids" Academic Press New York 1955 Vol. I p. 444 PROCEEDINGS NEWS AND ANNOUNCEMENTS The Research Fund.-The Research Fund of the Chemical Society provides grants for the assistance of research in all branches of Chemistry.About seven hundred pounds per annum is available for this purpose. Applications for grants will be considered in November next and should be submitted not later than November 15th 1957. Applications from Fellows will receive prior consideration. Reports on grants outstanding from previous years should be made by November 1st. Forms of application together with the regula- tions governing the award of grants may be obtained from the General Secretary. Corday-Morgan Medal and Prize.-This award consisting of a silver medal and a monetary prize of 200 guineas is made annually to the chemist of either sex and of British Nationality who in the judgment of the Council of the Chemical Society has published during the year in question the most meritorious contribution to experimental chemistry and who has not at the date of publication attained the age of thirty-six years.Copies of the rules governing the award may be obtained from the General Secretary of the Society. Applications or recommendations in respect of the award for the year 1956 must be received not later than December 31st 1957 and applications for the award for 1957 are due before the end of 1958. Vacancy on Council.-Dr. V. M. Clark has been appointed to fill the vacancy in Constituency I caused by the retirement of Dr. G. W.Kenner who is taking up his appointment to the Heath Harrison Chair of Organic Chemistry at the University of Liverpool.Local Representative.-Dr. V. M. Clark has been appointed Local Representative for Cambridge in succession to Dr. R. N. Haszeldine who has been appointed to the Chair of Chemistry at the Man- Chester College of Science and Technology. International Conference on Co-ordination Chem- istry.-It was agreed at the Conference held in Rome in September that the next International Conference on Co-ordination Chemistry should take place in London in the spring of 1959 under the auspices of The Chemical Society. It was also tentatively agreed that the 1961 meeting should be held in the U.S.A. Since 1953 these Conferences have been held in alternate years under the auspices of national chem- ical societies in Denmark Holland and Italy. A full announcement giving the scope of the London Conference which it is expected will take place during the same week as the Anniversary Meet- ings of The Chemical Society and other details will be made as soon as possible.Elections to the FelIowship.42 Candidates for Fellowship whose names were given in the Proceed- ings for August were elected on September 25th. Deaths.-We regret to announce the deaths of the following Fellows Mr. A. Prideaux Davson (September lst) a Fellow of the Society for over 50 years. Dr. G. Harker (August 15th) of New South Wales Australia a Fellow since 1900. Mr. F. H. Highley (August 6th) of Catford S.E.6. Mr. B. C. L. Kemp (December 26th 1956) science master at Hereford Cathedral School. MI-.F. Stanbridge (July 1 1 th) of Loughborough.Mr. H. N. B. Palmer (July 22nd) a Director of Messrs. Maguire & Paterson Ltd. Dublin. Mr. M. Rigbi (July 27th) of the British Rayon Research Association Manchester. The Reverend A. F. Smethurst (August 15th) Canon of Salisbury Cathedral. Personal.-Sir Alexander Fleck K.B.E. F.R.S. has been elected President of the British Association for the Advancement of Science for 1958. Sir Robert Robinson received the Hofmann Memorial Medal on October 4th 1957 at the meeting of the German Chemical Society in Berlin. Professor F. L. Warren was elected Vice-President (Natal) of the South African Association for the Advancement of Science. Dr. S. I. Levy has been appointed a Queen’s Counsel. Professor W.Wardlaw has been appointed by the Minister of Works as a member of his Advisory Council on Building Research and Development. Dr. D. H. S.Horn has been promoted to Senior Research Officer in the National Chemical Research Laboratories South Africa C.S.I.R. Dr. B. J. Ayktt has been appointed Lecturer in Inorganic Chemistry at the University of Aberdeen as from October lst and Dr. 0. C. Musgrave has been appointed Lecturer in Organic Chemistry as from January lst 1958. Dr.E. P. Hart has been appointed Head of the Department of Chemistry and Biology at Sunderland Technical College. Dr. B. E. Dawson has been appointed senior science master at the Coopers’ Company’s School. Mr. H. D. Anderson has been appointed Manager of the Research and Development Establishment of the British-American Tobacco Co.Ltd. Dr. L. G. Groves has been appointed Managing Director of Davy British Oxygen Ltd. Dr. R. Owens has been appointed Director of Explosives and Chemical Production Ministry of Supply. OCTOBER 1957 Mr. D. W. H. Waite has been appointed associate director of Aspro-Nicholas Ltd. responsible for commercial development. Dr. Robert B. Woodward(Honorary Pro-fessor of Chemistry at Harvard has received the honorary D.Sc. degree at Harvard. The Institution of the Rubber Industry has awarded the Colwyn Medal to Dr. H. W.Melville for conspicuous services in the field of polymer science. Mr. T. E. Peacock has been awarded a General Fellowship by the Ramsay Memorial Fellowships Mr.A. Richmond has been awarded a research scholarship by the Gas Council. FORTHCOMING SCIENTIFIC MEETINGS London Thursday November 7th at 2.15 p.m. and 5 p.m. Symposium “Newer Preparative Methods in Organ- ic Chemistry.” Joint Meeting with the Fine Chem- icals Group of the Society of Chemical Industry to be held in the Large Chemistry Lecture Theatre University College Gower Street London W.C. 1. Thursday November 21st at 7.30 p.m. Meeting for the Reading of Original Papers. “The Chemistry of Bacteria. Part VII. The Structure of Violacein,” by J. A. Ballantine C. B. Barrett R. J. S. Beer Stephen Eardley Alexander Robertson B. L. Shaw and T. H. Simpson. “The Structure of Lamin-arin. Part I. The Main Polymeric Linkage.Part LI. The Minor Structural Features,” by Stanley Peat W. J. Whelan and H. G. Lawley. “Indicator Measurements in the System Acetic Acid-Zinc Chloride-Hydrogen Chloride,” by D. Bethell V. Gold and D. P. N. Satchell. “Aromatic Alkylation. Part 11. Zinc Chloride Catalysis of Diarylmethyla- tions in Acetic Acid,” by D. Bethell and V. Gold. To be held in the Rooms of the Society Burlington House W.l. (Abstracts of the Papers are available from the General Secretary.) Aberdeen Friday November 22nd at 7.30 p.m. Lecture “Polymerisation at High Conversion,” by Professor G. M. Burnett Ph.D. D.Sc. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held at Marischal College. (The Lecture by Dr.T. S. West which was to have been given on this date has been cancelled.) Thursday December 5th at 7.45 p.m. Lecture “Pesticides-Problems and Prospects,” by Dr. R. A. E. Galley Ph.D. A.R.C.S. D.I.C. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held at Marischal College. Birmingham Friday November 1 Sth at 4.30 p.m. Lecture “Carbon-14 Compounds,” by Dr. J. R. Catch. Joint Meeting with Birmingham University Chemical Society to be held in the Chemistry Department The University. Friday November 29th at 4.30 p.m. Lecture “Electron Interactions,” by Dr. J. W. Linnett M.A. F.R.S. Joint Meeting with Birming- ham University Chemical Society to be held in the Chemistry Department The University.Bristol Thursday November 14th at 5.30 p.m. Social Evening. Joint Meeting with the Royal Insti- tute of Chemistry and the Society of Chemical Industry to be held in the University Senior Com- mon Room. Thursday November 21st at 5.15 p.m. Lecture “Silicones-An Introduction to their Chem- istry and Applications,” by Dr. G. G. Freeman D.Phil. F.R.I.C. Joiht Meeting with the Student Chemical Society to be held in the Chemistry Department The University. Thursday November 28th at 5.15 p.m. Lecture “The Uses of Models in Chemistry,” by Professor D. €3. Everett M.B.E. D.Phi1. Joint Meeting with the Student Chemical Society to be held in the Chemistry Department The University. Thursday November 28th at 7 p.m. Social Evening.Joint Meeting with the Royal Insti- tute of Chemistry and the Society of Chemical Industry to be held at the Technical College Cheltenham. Thursday December 5th at 6.30 p.m. Lecture “Design and Operation of Waste-heat Boilers,” by Captain W. Gregson. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in the Chemistry Department The University. Cambridge Friday November lst at 8.30 p.m. Lecture “Heterogeneous Polymerisations,” by Pro- fessor C. E. H. Bawn C.B.E. Ph.D. F.R.S. Joint Meeting with the University Chemical Society to be held in the University Chemical Laboratory Lens- field Road. Friday November 8th at 8.30 p.m. Lecture “Modern Developments in Organic Chem- ical Industry,” by Dr.R. Holroyd M.Sc. Joint Meeting with the University Chemical Society to be held in the University Chemical Laboratory Lens- field Road. Friday November 29th at 8.30 p.m. Lecture “Gibberellic Acid-a Remarkable Plant- growth Promoter,” by Dr. J. MacMillan. Joint Meeting with the University Chemical Society to be held in the University Chemical Laboratory Lens- field Road. Edinburgh Thursday November 14th at 7.30 p.m. Lecture “Biradicals,” by Dr. A. F. Trotman-Dickenson. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in the Lecture Room of the Royal Society of Edinburgh 24 George Street. Thursday December 5th at 7.30 p.m. Lecture “Physical Chemistry in the Dyestuffs In- dustry,” by Dr.D. s.Davies. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in the Lecture Room of the Royal Society of Edinburgh 24 George Street. Glasgow Friday November 15th at 7.15 p.m. Meeting for the Reading of Original Papers to be held in the Royal College of Science and Technology. Friday December 6th at 7.15 p.m. Lecture “William Ramsay a Glasgow Man,” by Dr. A. Kent MA. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held in the Royal College of Science and Technology. HUll Thursday November 14th at 7.30 p.m. Lecture “The Chemistry of Vitamin B12,”by Profes- sor A. W. Johnson M.A. Ph.D. Joint Meeting with the Royal Institute of Chemistry to be held in the Organic Chemistry Lecture Theatre The University.Thursday November 28th at 6 p.m. Lecture “Drugs used in the Treatment of Hyperten- sion,” by Dr. H. R. Ing F.R.S. Meeting arranged PROCEEDINGS by the University Student Chemical Society to be held in the Organic Chemistry Lecture Theatre The University. Thursday December 5th at 5 p.m. Lecture “Water-repellency,” by Professor N. K. Adam Sc.D. F.R.I.C. F.R.S. Meeting arranged by the University Student Chemical Society to be held in the Organic Chemistry Lecture Theatre The University. Irish Republic Friday November lst at 7.45 p.m. Lecture by Professor F. S. Spring D.Sc. F.R.S. Joint Meeting with the Werner Society to be held in the University Chemical Laboratory Trinity Col- lege Dublin.Leeds Monday November 11 th at 7 p.m. Royal Institute of Chemistry Symposium “The Training of the Chemist,” to be held in the Chem- istry Lecture Theatre The University. Friday November 15th at 6.30 p.m. Official Meeting and Tilden Lecture “Crystalline Ion-exchangers,” by Professor R. M. Barrer Sc.D. F.R.S. to be held in the Chemistry Lecture Theatre The University. Liverpool Thursday November 21st at 5 p.m. Lecture “Recent Studies in Relation to Biosyn- thesis,” by Professor A. J. Birch M.Sc. D.Phi1. Joint Meeting with the University Chemical Society and the University Biochemical Society to be held in the Chemistry Lecture Theatre The University. Newcastle and Durham Friday November lst at 5.30 p.m.Bedson Club Lecture “The Structure of Vitamin B12,” by Dr. D. Crowfoot Hodgkin F.R.S. To be given in the Chemistry Building King’s College Newcastle upon Tyne 1. (All Fellows are invited.) Monday November 4th at 5.15 p.m. Lecture “Molecular Engineering,” by Dr. H. L. Riley A.R.C.S. D.I.C. F.R.I.C. Joint Meeting with the Durham Colleges Chemical Society to be held in the West Building Science Laboratories The University Durham. Friday November 15th at 4 p.m. Meeting for the Reading of Original Papers. To be held in the Chemistry Building King’s College Newcastle upon Tyne 1. OCTOBER 1957 Monday November 1 Sth at 5.15 p.m. Lecture “cycloPentadieny1-and Benzene-Metal Compounds,” by Professor G.Wilkinson Ph.D. A.R.C.S. Joint Meeting with the Durham Colleges Chemical Society to be held in the West Building Science Laboratories The University Durham. Friday November 22nd at 5.30 p.m. Bedson Club Lecture “Recent Studies in Relation to Biosynthesis,” by Professor A. J. Birch M.Sc. D,Phil. To be given in the Chemistry Building King’s College Newcastle upon Tyne 1. Northern Ireland Thursday November 14th at 7.15 p.m. Lecture “Some Aspects of the Structural Chemistry of Proteins and Nucleic Acids,” by Professor H. D. Springall M.A. D.Phil. F.R.I.C. Joint Meeting with the Royal Institute of Chemistry and the Society of Chemical Industry to be held at the Queen’s University Belfast. North Wales Thursday November 7th at 5.45 p.m.Lecture “Studies in the Chemistry of Flavonoids,” by Professor T. S. Wheeler D.Sc. F.R.I.C. Joint Meeting with the University College of North Wales Chemical Society to be held in the Department of Chemistry University College of North Wales Bangor. Thursday November 21st at 5.15 p.m. Joint Meeting with the University College of Wales Chemical Society to be held in the Edward Davies Chemical Laboratories Aberystwyth. Nottingham and Leicester Monday November 4th at 4.30 p.m. Lecture “The Chemistry of Actinomycin,” by Pro-fessor A. w. Johnson M.A. Ph.D. Joint Meeting with the University of Leicester Chemical Society to be held at the University Leicester. Monday November 18th at 4.30 p.m. Lecture “Gas Chromatography,” by Mr.C. S. G. Phillips M.A. Joint Meeting with the University of Leicester Chemical Society to be held at the University Leicester. Oxford Monday November 1 1 th at 8.15 p.m. Lecture “Synthesis of Cell Constituents from Two- carbon Compounds in Micro-organisms,” by Pro- fessor H. A. Krebs F.R.S. Joint Meeting with Qxford University Alembic Club to be held in the Jnorganic Chemistry Laboratory. Monday November 25th at 8.15 p.m. Lecture by Professor R. S. Nyholm D.Sc. F.R.I.C. Joint Meeting with Oxford University Alembic Club to be held in the Inorganic Chemistry Labora- tory. St. Andrew’s and Dundee Friday November Sth at 5.15 p.m. Lecture “Polymerisation at High Conversion,” by Professor G. M. Burnett Ph.D. D.Sc. Joint Meeting with the University Chemical Society to be held in the Chemistry Department St.Salvator’s College St. Andrew’s. Friday November 15th at 5.15 p.m. Lecture “Seaweeds and their Utilisation,” by Dr. F. N. Woodward C.B.E. F.R.I.C. Joint Meeting with the University Chemical Society to be held in the Chemistry Department St. Salvator’s College St. Andrew’s. Sheffield Thursday November 7th at 7.30 p.m. Lecture “The Chemical Pharmacology of the Blockade of Adrenaline,” by Professor N. B. Chapman M.A. Ph.D. Joint Meeting with the Royal Institute of Chemistry and Sheffield Univer- sity Chemical Society to be held in the Chemistry Lecture Theatre The University. Thursday November 21st at 7.30 p.m. Lecture “Nuclear Magnetic Resonance,” by Dr.R. E. Richards M.A. Joint Meeting with the Royal Institute of Chemistry and Sheffield University Chemical Society to be held in the Chemistry Lecture Theatre The University. South Wales Monday November 11 th at 5.30 p.m. Tilden Lecture “Crystalline Ion-exchangers,” by Professor R. M. Barrer Sc.D. F.R.S. To be given in the Chemistry Department University College Cardiff. Friday December 6th at 6 p.m. Lecture “Some Recent Developments in the Chem- istry of Organometallic Compounds,” by Professor G. E. Coates M.A. D.Sc. F.R.I.C. Joint Meeting with the University College of Swansea Chemical Society to be held in the Chemistry Department University College Swansea. Southampton Friday November 29th at 5 p.m. Lecture “Hydrocarbon Compounds of Transition Metals,” by Professor G.Wilkinson Ph.D. A.R.C.S. Joint Meeting with the University Chemical Society to be held in the Chemistry Department The University. 296 PROCEEDINGS OBITUARY NOTICES EMILY GERTRUDE TURNER 1888-1956 MISSE. G. TURNER, who died on June 15th 1956 at her home in Rotherham where she had been living since retirement in 1953 from her lectureship in Chemistry had spent almost the whole of her work- ing life in devoted and distinguished service to the University of Sheffield. Born in Rotherham on April 16th 1888 she went to school there and at the age of 18 entered the recently established Sheffield City Training College for Teachers. Having already obtained the matricula- tion qualification she was able under the rules then in force to register as a degree student at the University while remaining attached to the Training College.Three years later in 1909 she graduated B.Sc. in Chemistry Mathematics and Education and having distinguished herself in Chemistry took the Honours course the following year again with outstanding success and proceeded on it to M.Sc. After a further year of research and another in taking the University’s Diploma in Education she became science mistress at the Rutherford Girls’ High School at Newcastle. Her exemplary record had not however been forgotten by W. P. Wynne who then occupied the Chair of Chemistry and soon after the outbreak of war in 1914 when all but one of his regular staff had left for war service she returned to Sheffieid Univer- sity at his invitation as a temporary assistant lecturer and took charge of the main elementary chemical laboratory in which all first-year students were taught.So began an appointment which was to prove far from temporary and only came to an end with her retirement 38 years later. Her teaching duties were always exacting and she gave much time to administrative work in the Chemistry Department but on occasion she was able to undertake research and to publish in col- laboration with other members of the Department work on ring systems and on derivatives of naphtha- lene and of toluene. She also gave much assistance to Wynne in the preparation of his articles in succes- sive issues of Thorpe’s Dictionary of Applied Chemistry.But it is as a teacher that she excelled and it is as such that she will be remembered with gratitude- and some awe-by the generations of students who passed through her laboratory. Her earlier experience in school stood her in good stead here for the first- year classes contained a large proportion of students to whom chemistry was only an ancillary to their main interests and some of them were ill prepared. For many years she conducted a special elementary lecture course for those not ready for the full inter- mediate class and later she took over the whole intermediate work. As a lecturer she was clear as simple as her subject matter allowed and always conscious of the difficulties of the student.But it was in the laboratory where she met each student individually that her qualities shone most brightly. She had neither time nor patience for a student who did not want to learn-and he soon realised it-but for anyone who meant business however dull he might be no trouble was too great for her to take no explanation too simple to repeat no technique too easy to demonstrate once again. It is not sur- prising that the rowdiest students were attentive in her classes that her laboratory however full could at any time have been photographed for publication or that she herself was held in affection as well as respect. Her students now scattered in many walks of life will remember her as a truly remarkable teacher and a trusted friend.A. W. CHAPMAN HENRY TERREY 1889-1954 HENRY a Fellow of the Society and a former TERREY Member of Council (1 928-3 I) died suddenly on Christmas Eve 1954 at Blackheath Kent. He was born in Bishop’s Waltham Hampshire on July 30th 1889 the second son of William H. Terrey. He was educated at Peter Symond’s School Winchester and entered University College London in 19 10 begin-ning in that year a connexion with the College and its Department of Chemistry that ended only with his death forty-four years later. He graduated B.Sc. (Honours Chemistry) in 1913 having passed the examination a year earlier in the last year of Sir William Ramsay’s tenure of the Chair of Chemistry. He was appointed Demonstrator in Chemistry to Medical Students for the Session 1913-14.A year later he was appointed Assistant in the Department OCTOBER 1957 of Chemistry and held that post from 1914 to 1922 when he became Lecturer in Analytical Chemistry. During the First World War he served as a research chemist to the Admiralty on the production of hydrogen (1915-1 8) and later he carried out further work for the Admiralty on signalling (1919-20). He was promoted Senior Lecturer in Chemistry in 1929 and Reader in 1937. In 1952 he was elected to the Chair of Chemistry which had become vacant by the death of Professor S. Sugden. In his earlier years on the staff of the Department of Chemistry he had been appointed (1919) Lecturer in Dental Metallurgy to University College Hospital Medical School and he retained this appointment until 1939.During the Second World War he worked with the senior students of the Department of Chemistry accom- modated in the University College of Wales at Aberystwyth. With characteristic devotion to his College he held many offices including membership of the College Committee the Managing Sub-Com- mittee and the Finance Sub-Committee. He served on the Professorial Board and for a number of years he was Tutor to Science Students. From 1953 to 1954 he was Dean of the Faculty of Science. In the Univer- sity of London Terrey was long a member of the Board of Examiners in Chemistry and discharged the heavy duties of Chairman for six years (1948-54). He was also a member of the Board of Studies in Chemistry and Chemical Industries member of the Board of Staff Examiners for External Students in Chemistry and Chairman of the Board of Studies (Physics and Chemistry) Sub-Committee in Crystallography.Always keenly interested in all undergraduate activities he was President of the Chemical and Physical Society in 1936-37 and Honorary Treasurer of the Union Society from 1942 (effectively from 1939) until his resignation in 1952 on being elected Professor of Chemistry. Terrey’s teaching was mainly concerned with inorganic and analytical chemistry and it was in these fields that he made his varied original contribu- tions. Of these two great branches of chemistry he possessed a vast and almost encyclopaedic knowledge the envy and the resort of many in search of refer- ences as it was immediately available without the necessity of following trails through standard works and abstracts and journals.Terrey’s original work reflected this versatile interest in his subject and his publications included researches on the hydrates of salts platino- and platini-cyanides the sub-oxides of lead and thallium platini-platino-chloride and iridi-irido-chloride elec- trodes dental alloys and dental metallurgy the coagulation of colloidal gold the suboxides and sub-halides of cadmium the crystal structure of silver subfluoride and of mercury and copper and copper amalgam the X-ray analysis of copper-silver and copper-zinc alloys indium dichloride cobalt-ammines germanous oxide and sulphide and similar problems.He contributed for several years to the Society’s Annual Reports and published an interest- ing centenary study on Edward Turner (1796-1 837) the first professor of chemistry in his College. Gentle and tolerant and kindly in all his ways Terrey was greatly beloved by his colleagues and by the many hundreds of students whom he had taught and trained. All became his friends and by all he was affectionately referred to as “Henry”. He was widely read in the English novelists and poets. The minute- ness of his knowledge of Scott and Dickens was astonishing and it almost rivalled his detailed knowledge of inorganic chemistry. Terrey married in 1919 Dorothy daughter of John Adams of Curdridge who survives him with the two daughters of the marriage.D. MCKIE. ERNEST ALEXANDER BRAUDE 1922-1956 ERNEST BRAUDEwas born in Germany in 1922 and died under tragic circumstances in his home at Kew on July 23rd 1956. He came to England at the age of fifteen and was naturalised at the age of twenty-four. He was educated at first privately and then at the Grammar School Farnham. From there he went to Birkbeck College for the year 1939-1940 and then transferred to the Imperial College where he spent the re-mainder of his academic life. At Imperial College he obtained the B.Sc. degree with first-class honours in Chemistry in 1942. He secured the Acland Essay Prize in 1940 and the Frank Hatton Prize in 1942. Although Braude’s scientific tastes were wide there was no doubt from the first that organic chemistry was the focus of his passionate interest.He was fortunate in that Sir Ian Heilbron was Professor of Organic Chemistry at the College at the time of his graduation and was able to give him inspiring leader- ship and guidance. He was also fortunate that his period at the College brought him immediately into touch with a group of singularly gifted and en-thusiastic young organic chemists who included E. R. H. Jones D. H. Hey A. H. Cook D. H. R. Barton A. W. Johnson R. Raphael L. N. Owen and B. C. L. Weedon. In this stimulating atmosphere Braude’s great talents quickly became apparent. Sir Ian Heilbron was able to offer him the post of private Research Assistant in the Organic Chemistry Depart- ment with funds supplied by the Rockefeller Founda- tion and he filled this position for three years.He joined the College staff proper in 1946 was promoted Lecturer in the following year and Reader in 1952. He succeeded me as Professor of Organic Chemistry in 1955. He received successively the Diploma of the College and the Ph.D. and D.Sc. degrees of London University. He won the Meldola Medal in 1950. He was elected to the Council of the Chemical Society in 1954 and was appointed a Tilden Lecturer. The first field in which he specialised under Heilbron and Jones was in the spectral properties of organic compounds. He retained his interest in this all his life and during his whole research career he personally directed the spectroscopic laboratories of the Organic Chemistry Department.As time went on the equipment became more elaborate and diversified. Work in the ultraviolet and visible region was extended into the infrared and vacuum-ultra- violet. His study of the electronic spectra of conjugated compounds is very well known and has been fully described in many papers special articles and books. He became a recognised expert in the subject. I would like however to add a word on his studies of the far or vacuum-ultraviolet as they are quite unknown to the general chemical public. He worked for long periods on this subject which is technically so difficult that it is practically an un- charted region for most organic chemists. Some very interesting results were obtained but Braude was not satisfied that they were sufficiently finished and reproducible to justify publication.In this and other fields he was an exacting critic of his own work. His interest in the application of absorption spectroscopy to problems of chemical structure widened into the use of other physicochemical methods. He was among the early organic chemists to use radioactive tracers and was responsible for the installation of the necessary equipment in the Organic Chemical department. Later with L. M. Jackman he pioneered a much more unusual de- velopment the thermochemical study of organic reactions in the liquid phase. Finally again on the side of technique he played a part in initiating a programme of work on the effect of penetrating radiation on organic structures.A great deal of this later work has not reached the state of publication. He had an intense interest in the mechanism of organic reactions and made many kinetic studies. For this purpose he used many of the physical tools already described. His studies on anionotropic changes were particularly fruitful and he joined with zest in the difficult and sometimes controversial task of interpret at ion. PROCEEDINGS But Braude was much more than a man with many techniques at his finger-ends and with wide theoretical interests. He joined with avidity in work of an altogether more rugged and pioneering kind. He made discoveries. He was not averse from forays into the field of natural-product chemistry.The atmosphere of the department with its multiplicity of interests from carotenoids to porphyrins helped him here. Perhaps his best known contribution to “classical” organic chemistry was the discovery of the lithium alkenyls a group of compounds for which he sub- sequently demonstrated a variety of reactions and uses. We made many useful studies directed to the synthesis of vitamin D and devised a new and convenient synthesis of the topically important thioctic acid. During the last five years of his life Braude and I collaborated with a number of able co-workers in investigations of the transfer of hydrogen between organic donors and acceptors. He gave much time and thought to this subject and was particularly concerned with the theoretical interpretation of the results.The research yielded a happy mixture of the excitingly unexpected and the orderly and rational. Both homogeneous and heterogeneous-metal-catalysed-reactions were studied. A very wide range of donors was used with acceptors ranging from quinones to free radicals. From the behaviour of hydroaromatic systems it was expected that it might be possible to effect aromatisation of blocked systems which involved the migration of alkyl groups. This was in fact achieved by the use of quinones and a novel type of Wagner-Meerwein change was thus realised. Braude was a most conscientious and able super- visor of research students. He chose goals which were attainable in subjects which were interesting stimulating and instructive.He was an excellent teacher a particularly lucid lecturer and a valuable contributor to discussions. He became increasingly in demand as a lecturer as his reputation grew and he visited many foreign institutions. He was always ready to help his colleagues by discussion and advice. He was a popular and respected member of staff and a good friend. He was happily married. His wife survives him. In a scientific career as in other walks of life a man must lay the foundations for many years on which he can build later. Braude had done this. His achievements were already considerable at the time of his death but there was little doubt in the minds of those who knew him well that the best was yet to be.It is a tragic loss that he should have died at a time when his attainments and opportunities alike pointed to a brilliant future. R. P. LINSTEAD. OCTOBER 1957 299 GERALD ROCHE LYNCH 1889-1957 GERALD ROCHELYNCHwas that rare combination of a medical man and a chemist. Because of his work in the criminal courts he was perhaps better known to the public than most chemists. Roche Lynch O.B.E. M.B. B.S. D.P.H. F.R.I.C. L.M.S.S.A. was born on January 12th 1889 and was the son of Dr. Jordan Roche Lynch of Notting Hill. He was educated at St. Paul’s School and commenced his training as a medical man at St. Mary’s Hospital with which he was more or less connected all his life. However from 1908 to 1910he specialised in chernistry,working under Professor H.E. Armstrong at the City & Guilds Institute. He was a surgeon in the Navy in the First World War and was then appointed Assistant Official Analyst to the Home Office working with Sir William Willcox. He became Senior Official Analyst in 1928 so that for a period of about 30 years he was constantly in the courts giving evidence in important murder trials especially those in which toxicology was involved. It is perhaps true to say that although keeping up his interest in medical matters he leant more and more to specialised analytical chemistry. Because of his unique knowledge and experience and particu- larly because of his strength of character he attained many honours and at various times he was President of the Medico-Legal Society (194649) Hon.Secretary (1932-36) and President of the Society of Public Analysts and Other Analytical Chemists (1936-37) and President of the Royal Institute of Chemistry (1946-49). He had the distinction of becoming a Master of a City Company being Master of the Society of Apothecaries of London (1951-52). He was a Fellow of the Chemical Society for nearly 50 years (from 1908). In spite of the high ofices he held he was by nature a quiet unassuming man but was characterised by considerable determination. Once he was con- vinced of anything it was hard to get him to change. He held strong views on people as well as on affairs but there was always a very gentle side to his nature. His hobbies were gardening-he was rarely without a home-grown carnation-photography and collect- ing antique clocks of which he had a valuable collection.He married Sybil Marguerite Pinnock in 1919 and she died at the early age of 29. Roche Lynch died on July 3rd 1957 in his home at Slough and is survived by his only child Mrs. Bridget David. D. W. KENT-JONES. APPLICATIONS FOR FELLOWSHIP (Fellows wishing to lodge objections to the election of these candidates should communicate with the Honorary Secretaries within ten days of the publication of this issue of Proceedings Such objections will be treated as confidential. The forms of application are available in the Rooms of the Society for inspection by Fellows.) Aft Harvey A.B. M.S. 2626 Arnold Way Corvallis Oregon U.S.A.Baker Ronald B.Sc. 22 Hackings Avenue Cubley Penistone nr. Sheffield. Basco Norman B.Sc. Ph.D. 54 Meadow Walk Harpen- den Herts. Boehm Ernest Eugen B.Sc. 143 Cyncoed Road Cardiff Glam. Chambers Robert Warner A.B. Ph.D. Department of Biochemistry New York University College of Medicine New York U.S.A. Crossley John. 27 Portland Gardens Chadwell Heath Essex. Dean Ronald Alfred B.Sc. 96 Staines Road Laleham Middlesex. Hart George Frederick James. 31 Pondfield Crescent St. Albans Herts. Humbelin Robert D.Phil. 27 Upper Park Road London N.W.3. Jenkins Philip Winder B.S. 40 Westgate Cambridge 39 Massachusetts U.S.A. Likar Lydia Julia Ph.D. 50 Hillfield Avenue London N.8. Luker Winnifred Ernestine. 10 Boscombe Road Merton Park S.W.19.McCoy George B.S. M.S. Ph.D. Pennsalt Chemicals Corporation P.O. Box 4388 Philadelphia 18 Penn- sylvania U.S.A. McGinn Francis Aloysius B.S. M.S. 38 Hamilton Street Stapleton S.I. New York 4 U.S.A. Parnell Edgar M7illiam B.Sc. 3 1 Belgrave Road Ilford Essex. Ross Daniel L. B.A. 305 Memorial Drive Cambridge Massachusetts U.S.A. Sasaki Hirooki B.Sc. Sasaki Institute for Medical Research No. 2,2-chome Kanda-Surugadai Chiyoda- ku Tokyo Japan. Stephenson Douglas John. 23 Waterbank Road Catford S.E.6. Treibs Wilhelm D.Phi1. Abtnaundorfer Str. 60 Leipzig-N. 24 Germany. Winfield Michael Hardy B.Sc. 12 Ranelagh Grove Nottingham. ADDITIONS TO THE LIBRARY Despre teoria proceselor de polimerizare si polimeri- zarea acetilenei.0. F. Solomon. Pp. 231. Editura Academiei Republicii Populare Romine. Bucurest. 1957. (Presented by the publishers.) Uber den Aufbau der Zinksulfid-Luminophore. N. Riehl and H. Ortmann. Monographien zu “Angewandte Chemie” und “Chemie-Ingenieur-Tech&”. No. 72. Pp. 58. Verlag Chemie GMBH. Weinheim. 1957. Advances in catalysis and related subjects. Vol. 9. Proceedings of the International Congress on Catalysis Philadelphia 1956. Edited by A. Farkas. Pp. 847. Academic Press Inc. New York. 1957. Metal ammine formation in aqueous solution theory of the reversible step reactions. J. Bjerrum. (Reprint of the 1941 edition.) Pp. 296. P. Haase and Son. Copen- hagen. 1957. (Presented by the publishers.) Handling and uses of the alkali metals the symposium presented before the Division of Industrial and Engineer- ing Chemistry at the 129th meeting of the American Chemical Society Dallas Texas.(Advances in Chemistry Series. No. 19.) Pp. 177. American Chemical Society. Washington. 1957. Bibliography of research on deuterium and tritium compounds 1953 and 1954 compiled by V. R. Johnson L. M. Brown and A. S. Friedman. (Nat. Bur. Stand. Circular 562 Suppl. 1 .) Pp. 3 1. U.S. Government Printing Office. Washington. 1957. (Presented by the publishers.) Progress in the chemistry of fats and other lipids. Vol. 4. Edited by R. T. Holman W. 0. Lundberg and T. Malkin. Pp. 289. Pergamon Press. London. 1957. The chemistry of organometallic compounds. E. G. Rochow D.T. Hurd and R. N. Lewis. Pp. 344. John Wiley and Sons Inc. New York. 1957. 1949-51 Bibliography of rubber literature (including patents). Pp. 600.American Chemical Society. Division of Rubber Chemistry. Akron Ohio. 1957. (Presented by the publishers.) H. Vogel’s Chemie und Technik der Vitamine. 3rd Edn. Edited by H. Knobloch. Vol. 2. Die wasserlaslichen Vitamine. Teil 2. Lieferung 2. Pp. 160. Ferdinand Enke Verlag. Stuttgart. 1957. Annual review of biochemistry. Volume 26. Edited by J. M. Luck F. W. Allen and G. MacKinney. Pp. 768. Annual Reviews Inc. Palo Alto California. 1957. Annual review of plant physiology. Vol. 8. Edited by A. S. Crafts L. Machlis and J. G. Torrey. Pp. 477. Annual Reviews Inc. Palo Alto California. 1957.Physiologische Chemie. Edited by B. Flaschentrager and E. Lehnartz. Previously known as Lehrbuch der Physiologischen Chemie by 0. Hammarsten. Vol. 2. Der Stoffwechsel. Part 2. Section b. Pp. 1428. Springer- Verlag. Berlin. 1957. Recent progress in hormone research proceedings of the Laurentian Hormone Conference 1956. Volume 13. Edited by G. Pincus. Pp. 646. Academic Press Inc. New York. 1957. “AnalaR’ standards for laboratory chemicals incor- porating improved standards for the analytical reagents originally designated as “A.R.”. Formulated and issued jointly by the British Drug Houses Ltd. and Hopkin and Williams Ltd. 5th Edn. Pp. 397. British Drug Houses Ltd. Poole. 1957. (Presented by the publishers.) Niende Nordiske Kemikermsde held at Aarhus 1956.Pp. 183. Nordiske Kemikermerde. Aarhus. 1956. (Pre- sented by Universitetets Fysisk-Kemiske Institut Copen- hagen.) Trabajos de la Tercera Reunion Internacional sobre Reactividad de 10s Solidos held in Madrid 1956. Volume 1. Pp. 730. C. Bermejo. Madrid. 1957. (Presented by the publishers.) Plant growth and man-made molecules. (Evening meeting of the Royal Institution held November 23rd 1956.) Pp. 19. Royal Institution. London. 1956. (Pre- sented by the Royal Institution.) Pilot plants models and scale-up methods in chemical engineering. R. E. Johnstone and M. W. Thring. Pp. 307. McGraw-Hill Book Co. Inc. New York. 1957. Chemicals a Financial Times survey. Monday August 12th 1957. Pp. 48. Financial Times Ltd. London.1957. (Presented by the Financial Times.) NEW JOURNALS Buletinul Institutului Politehnic Bucuresti from 1956 18. Chemical & Engineering Data Series from 1956,l. Journal of the Polarographic Society from 1957 (only one issue per year published no volume number given). Microchemical Journal from 1957 1. CHRISTMAS COMPETITION A PRIZE (book token &22s.) is offered for the best translation of a short piece (not more than 40 words) of well-known English verse or prose into the style too often used in scientific papers. For example “At this juncture it is pertinent that an enquiry should be initiated by us as to whether the object subtending a forward visible angle and positioned on a plane bisecting the minor corporate axis is-or is not-a dagger . . .” (Macbeth 11 i 33). Entries must be received by the Editor not later than first post on December 30th so that the winning entry may be published in Proceedings. The author’s name and if desired a pseudonym for publication should be given. The Editor’s decision will be final.