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Proceedings of the Chemical Society. July 1961 |
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Proceedings of the Chemical Society ,
Volume 1,
Issue July,
1961,
Page 229-272
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摘要:
PROCEEDINGS OF THE CHEMICAL SOCIETY JULY 1961 ~~~ ~~~~~~ ~ ~~ ~~~~~ ~ RECENT EXPERIMENTS TO TEST SOME ASPECTS OF RELATIVITY THEORY By T. E. CRANSHAW (A.E.R.E. HARWELL) IN Newtonian physics the quantity “mass” is a few percent. The most sensitive test of the introduced in two ways. In the first it enters as identity of the two quantities was made by the quantity multiplying the velocity to give the Eotvos using a torsion balance who found momentum p and Newton defined the force I; as identity to within a few parts in log. the rate of change of momentum. Thus the first An important consequence of the equivalence law of motion “every body continues in its state of inertial and gravitational mass is that no of rest or uniform motion in a straight line unless kinetic experiment can distinguish between a made to change that state by an external applied gravitational field and a constantly accelerating force” is a statement of the principle of con- system.A man inside a lift cage unable to see servation of momentum. If the mass is constant? out is unable to tell whether the cage is at rest we may write I; = p = mi = m2 or “the force on the surface of the earth or accelerating in a is equal to the product mass times acceleration.” region far from the gravitational fields of heavy The second way in which the mass enters is bodies. through the law of gravitation. This law states In the Newtonian account light is considered that there exists an attractive force between all to be a wave travelling in an all-pervading sub- bodies which is proportional to the product of stance? the ether just as sound is a wave travel- their masses and inversely proportional to the ling in air.The velocity of the wave in the ether square of the distance between them i.e. I = may be written as c. Then if an observer is Gm,m2/r2where G is a constant and r the travelling with velocity v the time taken for a distance. In particular the earth attracts bodies light wave to cover a distance I away from him with a force gm,since for laboratory experiments in the direction of his motion will be Z/(c + v). r can be taken as constant.* Now it is clear that If the light is then reflected back to the observer if the quantities defined in these two ways are the time taken will be Z/(c -v) and the total identical then all freely falling bodies are subject time is 21/41 -v2/c2).Light which travels along to an acceleration g independent of mass.This a path at right angles to his motion will take a result was known to Galileo to be true to within time 2Z/cd(l -v2/c2).To the first order the * Newton showed that spherical bodies behaved as if all the mass were concentrated at the centre. 229 difference between these times is Z/c.vZ/c2. The well-known Michelson-Morley experiment was an attempt to detect this difference by observing the interference of light which had travelled along two equal paths at right angles to each other. The fringe system was expected to change as the apparatus was rotated. This experiment and several others all failed to detect any relative velocity between the observer and the ether.Poincark Lorentz and others tried to explain this result by modifying the laws of Newtonian physics. In particular Einstein showed that the error in Newtonian physics lay in the concept of absolute velocity and time and that indeed the constancy of the velocity of light in different frames of reference in uniform motion with respect to one another was inherent in Maxwell’s equations. The new laws which govern the trans- formation between systems in relative motion are usually called the Lorentz transformation laws. Einstein showed that a consequence of the new laws was that a body emitting radiation would appear to lose mass and that the quantity of mass lost would be equal to E/c2where E is the energy radiated.For this reason he stated that the mass of a body was a measure of its energy content and remarked that the relation might possibly be tested in the case of the radioactive elements. Thus mass has entered into physics in yet a third way. In a further paper Einstein considered the question of the equivalence of an accelerated system and a system in which a gravitational field acts and suggested that the equivalence should be extended to include all physical pro- cesses. He called this postulate the principle of equivalence. Consider light emitted at time zero in a system whose velocity is zero at time zero but which is accelerating with acceleration$ Then the time taken to reach a point at a distance 1 in the accelerating system is Z/c.The velocity of the remote point will then beJEIc. Thus an observer at this point will find that the light has changed its frequency due to the Doppler effect by an amount 8v where Sv/v = rf/c2. Then by the principle of equivalence the shift of frequency when light travels a distance in a gravitational field g must also be gZ/c2. Einstein showed that this is in agreement with the idea that mass is a measure of the energy content and we can see PROCEEDINGS this very simply if we adopt a quantum picture. Consider an atom of mass M and let it be excited so that its mass becomes M +m.Now let the excited atom be raised through a height 1. The work done is (M +m)Zg. We now let the atom emit a quantum of radiation so that it is de-excited and its mass returns to the value M.If the atom is now returned to the original level the work done by it is MZg. If the quantum also returns to the original level it has by the con- servation of energy an extra amount of energy mgZ. The frequency of the quantum was original- ly given by hv = mc2 so that h8v = mgl. Thus 8v/v =gZ/c2as before. In this calculation we have only assumed that the mass m behaves in a gravi-tational field in exactly the same way as the mass M and that there are no other unexpected sources of potential energy. Thus an alternative statement of the principle of equivalence is that the inertial mass associated with energy is also acted upon by a gravitational field.The shift in frequency just calculated for two points separated by a distance I in a gravitational field g is just as ifthe gravitational field acted upon the quantum -as ifthe light had weight. A particular case of an accelerating system is a rotating system. A point on a disc at radius r rotating with angular velocity w is subject to an acceleration w2r,and the force acting on a mass at this point is mw2r. Thus the work done in moving a mass from the centre to a point at radius R is W = 1; mw2r dr = +mw2R2.By analogy with the discussion already given we would expect that for a photon starting from the centre and detected at radius R the shift of frequency 8vR = +w2R2/c2,a change of energy as if the centrifugal force acted upon the quantum.It is easy to see that if a quantum starts at a point at radius R,and is subsequently detected at another point radius R,then 8v/v =0. The value of shift can also be derived by con- sidering the point at radius R as having a trans-verse velocity v = wR. There is then a rela-tivistic Doppler shift given by 8v/v = iv2/c2= $02R2/c2.An alternative description is to say that clocks at the circumference of the disc where the velocity is v go at a different rate from clocks at rest at the centre of the disc and the relative difference in rate is again given by &v2/c2. It will be seen that the magnitude of the shifts involved is second order in l/c. Since the velocity JULY1961 of light is 3 x 1Olo cm./sec.it follows that the shifts are always extremely small. For example light emitted by the sun and received at the earth would be expected to show a shift towards the red end of the spectrum of two parts in lo6. From a satellite circling the earth a shift of the order of one part in lo9 might be expected. At the surface of the earth the shift is about one part in 10ls per cm. difference of height. Attempts have been made to observe the red shift in light from the sun but the results are in- conclusive. The right order of shift is observed in light coming from near the limb of the sun but at the centre almost no shift is observed. The explanation of these measurements is not clear but is presumed to lie in other effects which are difficult to allow for.Preparations are also in progress to attempt to observe the shift in fre- quency of a casium clock installed in a satellite. In this case the shifts are complicated by the motion of the satellite and are close to the limit of detection. The picture has been completely changed by the discovery of R. L. Mossbauer concerning the emission of nuclear y-rays. It has been known for many years that the “natural width” of some y-rays given by the uncertainty principle is ex- tremely narrow. For example if the lifetime of a nuclear state is sec. the uncertainty in energy is about ev. If the energy of the level is 10 kev the relative width is 10-l2. This means that the relative width in frequency is also 1O-l2. However it is usually not possible to utilise this extreme narrowness for the following reason.If the atom is free there will be a recoil when the y-ray is emitted. The momentum in the y-ray is E/c and therefore the momentum in the recoil- ing atom is also E/c. The energy of the atom is then p2/2M =E2/2Mc2where M is the mass of the atom. In the case just quoted if we put M x 50 the recoil energy is about lo4 ev-lo5 times greater than the width of the line. This energy is abstracted from the y-ray and if we tried to absorb the y-ray by resonance in another nucleus the deficit would be doubled. If one attempts to use the atom bound in a lattice bound much more tightly than ev one then finds that the line is disturbed by thermal motions which introduce a Doppler shift.We can estimate the magnitude of the shifts to be expected. Consider the emitter of 231 electromagnetic waves of angular frequency w and wavelength A. Then at a point x the electric field can be written E ==Eo cos(ut -2~~/)c) Let us suppose that x is a function of time x = vt representing a point moving with constant velocity. Then E =EO COS(W-2~v/)c)t Thus as a result of the motion we see that the angular frequency is changed by an amount 2~v/A,and if Y is the frequency Sv/v =v/c.This is the simple Doppler shift. We can make an estimate of v for the crystal vibrations by assuming some model of the crystal lattice. If we put Mi2 = $kT and assume M x 50 proton masses we find v x lo4 cm./sec. and 6v/v = 3 x lo-’.Thus the shifts introduced by the thermal motion are of the order of a million time larger than the natural line width and the line is smeared out into a relatively wide band. The essence of Mossbauer’s discovery lies in the following considerations. In the expression for the wave given above let us put x = a cos utt,corresponding to an atom oscillating with angular frequency utand amplitude a. Then a E =E cos[w -(cos wt)t]t,where A =A/27r A This corresponds to a frequency-modulated wave and well-known theory states that if a/X is small the resultant wave can be analysed into a fundamental of angular frequency w together with sidebands at frequencies (w nut). The condition that a/X be small corresponds to the statement that the amplitude of the oscillation in the crystal lattice should be small compared with the wavelength of the emitted y-ray.If this con- dition is satisfied the fractional amount of energy in the fundamental is given by f =exp [-(a/2X)2]. The value of a can again be estimated from a model for the crystal lattice and will depend on the temperature and the lattice constants. For example we may say as before kT = MG2 = $Ma2ut2where utis the angular frequency of the vibration of the atom. From the Debye model themeanvalue of 1/wt2 is 3/Wo2 wherew is given by Ziw =k8,8is called the Debye temperature for PROCEEDINGS the crystal and X = k/Eywhere Ey is the energy of the y-ray and f = exp (-a) The expression Ey2/2Mc2is the recoil energy given to the atom Er.We may then write 6TEr f= exp -(m) which displays how the fraction of energy remaining in the unshifted fundamental depends on the recoil energy and the value of 8 which describes the “stiffness” of the lattice. For the case of 57Fe for which the figures given earlier are approximately true about 60% of the radia- tion is emitted in the undisturbed fundamental. It is this radiation emitted in a line whose rela- tive width is about 10-l2 which has been used to perform experiments to test the predictions of relativity theory. The nuclei act as resonators and in radio engineering language they have a Q -10l2. If the radiation from an iron foil con- taining 57C0which decays to give 57Fe in the excited state is allowed to pass through a second foil containing 57Fe some of the radiation will be resonantly absorbed and the intensity of the beam will be weakened.It will be seen from the figures given earlier that the shift in the earth’s gravitational field in a height of 10 m. is one part in 1015. Thus we have to measure a shift of the order of one- thousandth of a line width. It will be impractical to attempt to observe such a small shift by weak- ening of the absorption of the radiation caused by the small detuning. But we can measure the shift by a trick. The energy of the emitted radia- tion is caused to be increased or decreased by a small amount by imparting velocities jl v to the source. If v is chosen to give Sv/v -10-l2 then the emitted radiation will have a frequency just on the steep part of the resonance curve.Then a change in frequency due to the gravitational field will cause the absorption to increase on or,e side of the resonance and to decrease on the other. Thus the difference between the counts observed in a counter taken severally with the positive and the negative velocity will be a sensitive indication of the exact position of resonance. Measurements taken at two different heights or with the ap- paratus inverted yield the effect due to the gravitational field. It is impractical to make the difference in height very much greater than 10 metres so that the shift is always a fraction of a line width. The same difficulty does not arise in the case of an experiment in a rotating system.Here with an apparatus consisting of two dural plates of 6” diameter containing the source clamped at the centre and a strip of absorber at the circum- ference rotated at 500 c.P.s. the shift is of the same order as the line width. Thus the “detuning” can be observed directly as an increase in count- ing rate as the speed of rotation of the disc is increased. These experiments are being carried out at Harvard and at Harwell. At the present time the Harvard experiment on the gravitational shift shows agreement with the relativistic expression within the experimental error of 5% and the experiment in the rotating system at Harwell shows agreement within 10 %. What other effects besides Doppler velocity and gravitational or accelerated systems can cause changes of frequency? There are two which are most important these are the temperature effect and one more properly called the isomer effect but sometimes called the chemical effect.The temperature effect may be seen in the following way. The y-ray quanta with which we are concerned the quanta in the undisturbed fundamental line may be considered to be those emitted for which the mean velocity during the emission is zero. However it will not be true that the mean square velocity is zero and according to the relativity theory clocks in a moving system go at a different rate when seen from a stationary system the difference being given by 6t/t = +v2/c2.Thus the shift in frequency can be simply estimated as Sv/v = Mv2/2Mc2,where Mv2is the energy of the atom in the lattice.If we equate this with the thermal energy we have Sv/v U/2c2,where U is the energy per unit ==I mass. Then a8 -iu 1 @ -S‘T=252CD where C is the specific heat. Thus the frequency has a temperature coefficient of magnitude C,/2c2.For iron this has the value 2.2x 10-15/0~ and must be taken into account where shifts small compared with a line width are measured. JULY 1961 The isomer shift is somewhat more difficult to see but comes about through the field at the nucleus produced by the atomic electrons. The excited state of the nucleus may be considered as due to the motion of a proton in the attractive field of the other nucleons in the nucleus.An additional small field of force is provided by the atomic electrons which modify the resultant field in which the proton moves. The chemical state of the atom thus has an influence at the nucleus. A shift can also be produced by the presence of impurity atoms in the lattice. The effect can be utilised in the experiments in the rotating system. If a suitable absorber and source can be produced in which a shift of about 10-l2exists then the system is highly sensitive to a small extra shift because the absorption is already occurring on the steep sides of the resonance curve. Moreover it is then possible to determine the sign of the shift which is not possible if the resonance was originally exact. To conclude this discussion we might draw attention to the support that the experiments have given to those predictions of relativity theory often called the “twin paradox.” The paradox as usually stated says that if one of two twins takes ajourney into space with velocity v then clocks for him and presumably for his life processes go slower by an amount &v2/c2 and since this does not change sign for his return journey he will return as a younger man than his brother.It has been argued that in this account the effects of accelerations have been left out. However in the experiments in the rotating system and also in the vibrating atom the shifts which are observed are just as the rela- tivity theory predicts though in one case the acceleration is constant and in the other oscillatory and very large.The Oxford “History of Technology” By E. F. CALDIN THEcompletion of the five massive volumes of the Oxford “History of Techno1ogy”l is an event worthy of special notice since they will doubtless remain for a long time the most important collection of studies in this field. Each volume contains a series of essays by accredited experts organised under such general headings as primary production manufacture material civilisation and communications. There are useful chronological tables and side-glances at general history. The writing is clear and workman- like the editing and production excellent. There are hundreds of admirable illustrations. The successful fruition of such an enterprise is a remarkable achievement.Some will cavil at the word “history” in the title for in the main this is “an encyclopaedia not a history a work of reference rather than a work of interpretation.”2 The editors are aware that they are not providing a social history; in the introduction to the second volume they modestly claim that their work is “an attempt . . . to illustrate those activities that provide material amenities and to show how these arise develop and depend on each other. It is thus concerned mainly with the nature and evolution of processes techniques and device-in fact with technology proper and not with its social and economic repercussions . . . These volumes are per- haps more in the nature of annals than of history proper but true history cannot be written until the relevant events have been adequately marshalled.When completed this “History” will provide a moderately comprehensive survey of the develop- ment of western te~hnology.”~ It certainly does pro-vided that we agree to mean by “technology” simply the study of techniques whether scientific or em- pirical; for techniques based on scientific under- standing do not appear until the later volumes. In this short article I can only pick on a few topics that may illustrate the scope of the work and the questions it suggests. CHEMISTRY CHEMICAL AND INDUSTRY-Chemical 1ndustries.The chapters of technical interest to chemists are those dealing with chemical arts and industries and with the production and use of metals.Between them these chapters survey the whole period from the ancient civilisations of Mesopotamia and Egypt to the end of the nineteenth “A History of Technology,’’ edited by Charles Singer E. J. Holmyard A. R. Hall and Trevor I. Williams. Vol. I From Early Times to the Fall of the Ancient Empires c. 500 B.C. Vol. 11 The Mediterranean Civilisations and the Middle Ages c. 700 B.C. to A.D. 1500. Vol. 111 From the Renaissance to the Industrial Revolution c. 1500 to c. 1750. Vol. IV The Industrial Revolution c. 1750 to 1850. Vol. V The Age of Steel c. 1850 to 1900. (Oxfard at the Clarendon Press 8 mineas each volume.) This work is designated as HT in references below. Asa Briggs “Machines and History,” New Statesman December 20th 1958 p.885. hT,Vol. 11 p. vi. century. The simple metallurgy of gold silver lead copper antimony tin and bronze had been mastered by about 2000 B.c. and that of iron and steel by about 1400 B.C. ;the contribution of these metals to civilisation has been immense through their use in tools vessels coinage weapons and je~ellery.~ Dis-coveries and improvements were made empirically and the technical skill in practical chemistry and metallurgy revealed by the great sixteenth-century treatises of Agricola Biringuccio and Ercker is very remarkable. Pre-scientific industrial chemistry covered a surprising range of products for use in such crafts as dyeing preserving painting glass-making ceramics soap-making and gunpowder manufac- t~re.~ Apart from the substitution of coal for wood as a fuel there seems to have been little in the chem- ical industries of the mid-eighteenth century as described in the French “Encycloptdie,” that would have surprised a late medieval practitioner.The great change in the scale and range of the chemical industry appears to have begun with the growth of the alkali industry.6 Alkali was needed by glass-makers soap-boilers and textile manufacturers (for bleaching). It was made from wood-ashes. Wood or charcoal was also needed for fuel in iron-smelting and metal production generally. There is much evidence of a timber famine in the late seventeenth century and a search for substitutes began. The fuel problem was solved by using coal; the alkali problem was solved at the end of the eighteenth century by the Leblanc process based on common salt and sulphuric acid.The solution was so successful that the industries using alkali became the focus of heavy chemical industry and set the pattern for its develop- ment until nearly the end of the nineteenth century.’ The later history of the Leblanc process and its replacement by the ammonia-soda and the Castner- Kellner process are a fascinating story of technical difficulties overcome.8 They take us into the era of scientific chemistry and later chapters deal with the history of dyestuffs explosives and fine chemicals in the nineteenth cent~ry.~ Chemical Science and Chemical Industry .-It is natural to enquire into the historical relations of chemical industry with the chemical science of which it now makes so much use.Until the late eighteenth century the chemical industries were a collection of PROCEEDINGS crafts using empirical methods. Synthetic alkali and bleaching-powder were the first fruits of the applica- tion of scientific chemistry to industry. The textiles industry its scale multiplied by the use of machinery worked by steam was probably the greatest stimulus to these developments in large-scale chemical prac- tice. It did not however have any appreciable in- fluence on chemical science as is sometimes sup- posed; it simply made use of chemical knowledge as it progressed.1° For instance it relied on natural dyes for most of the nineteenth century; chemistry before 1850 had not progressed far enough to dis- cover the structures of the known colouring-matters so that there was no scientific way to make new ones.Modern chemistry was built on the work of Black Priestley Lavoisier and Dalton whose ideas owed little or nothing to the problems of chemical industry. Lavoisier’s theory of elements and Dalton’s atomic theory were the products of inquisitive men working in laboratories not of practical industrialists. No doubt the chemical industries provided apparatus and some of the chemicals but they suggested neither the essential problems nor the ideas to solve them. The Concept of Chemical Purity.-One funda-mental concept of chemistry does however appear to owe something to industrial experience especially that of metal extraction the concept of chemical purity of individual chemical substances.This is not an obvious notion. Most of the materials commonly used by man until recent times-such as wood paper textiles and foods-are more or less impure in the chemical sense; even the air and water in different localities smell and taste differently. Ordinary ex- perience might suggest that an indefinite variation of properties is more likely than sharp divisions between different kinds of material. Moreover metal-workers have known from antiquity that by alloying one can produce progressive variations ; indeed one can vary the hardnessll and even the density12 of a metal merely by hammering it or annealing it. It is not surprising that Aristotle’s theory of matter re flected this situation; aiming at a qualititative description of the multifarious bodies around us he supposed that his four elements could be present in any proportions and changed one into another.Only prolonged experience of fairly well-purified sub- HT Vol. I Chap. 20; Vol. 11 Chap. 2; Vol. 111 Chap. 2. For the later history of the extraction of metals see Vol. IV Chap. 4; Vol. V Chaps. 3 and 4. Cf. a recent article by J. R. Partington in these Proceedings 1959 p. 241. HT Vol. I Chap. 11; Vol. 11 Chap. 10; Vol. 111 Chap. 25. Cf. F. Shenvood Taylor “A History of Industrial Chemistry ” (London Heinemann 1957). HT Vol. IV Chap. 8. HT,Vol. IV p. 242. HT Vol. V Chap. 11. HT Vol. V Chaps. 12 13 14. loHT Vol.V Chap. 12. l1 Cf. HT VOl. I pp. 600-601. l2 Cf.HT,Vol. VIII p. 68. JULY 1961 stances altered this general opinion. The concept of chemical purity was not accepted in the sixteenth century but it was taken for granted by Black and later chemists in the eighteenth and though it was implicitly denied by Berthelot it was reinstated by the work of Proust early in the nineteenth century. The origins of the notion of chemical purity do not appear to have been fully worked but the preparation of metals may have been one of its sources. The separation of pure silver from lead and that of pure gold from silver seem to have been achieved by lo00 B.c. and as early as the second century B.C. there is a description of the refining of crude gold by a form of cupellation;14 but there were no standards or tests for pure gold or silver.How- ever Ercker and Biringuccio in the sixteenth century seem from some passages in their works to have used the idea of pure metals which when mixed con- stitute alloys. Another source may have been tests on chemicals used in industrial processes. For instance alum for mordanting must be freed from iron; this can easily be done by crystallising and alum was the first salt to be used in a nearly pure state.15 The next was probably saltpetre which was recrystallised for use in gunpowder.16 For such chemicals performance depended on purity; but we know little of the methods adopted to maintain standards. A third possible source suggested by Dr.Holm-yard may have been the experience gained after Paracelsus introduced inorganic materials into medicine. He believed the efficiency of such remedies to lie in something hidden in them an arcanum; this may have led to attempts to concentrate the active ingredient which would lead to the discovery that repeated purification made no difference to the pro- duct after a certain point was reached and so to tests and standards of purity.17 None of these suggestions however seems to have been followed up systema- tically. TECHNIQUES IN THE PRE-SCIENTIFICERA The first three volumes of this “History” are concerned with crafts and industries developed for the most part empirically without the aid of science. The progress recorded is very remarkable.In any craft the first step is the most difficult. Millenia elapsed before men discovered in neolithic times how to produce food instead of hunting or collecting it. The discovery of agriculture led to the settlement of communities in villages and later in towns and other advances followed relatively quickly the invention of weaving the development of pottery and the in- troduction of the wheel.18 Again metals were prob- ably not used at all before about 5000 B.c. but gold and silver objects from Ur (before 2500 B.c.) show magnificent technique.lg Writing began during the fourth millenium B.c. in the form of pictographs which were simply elaborations of pictorial represen- tations; within a few hundred years the Sumerians were using signs to represent syllables-sounds rather than meanings-and so had begun the line of development that led in the second millenium to alphabetic writing.20 Once the basic discoveries were made progress was relatively rapid.Certain crafts show a rapid early development and a remarkable continuity from Greek and Roman (or earlier) civilisations until the industrial revolution or even later. Goldsmiths’ and silversmiths’ tech- niques were well understood in ancient Mesopotamia and Egypt and the products of Greek Celtic Byzan- tine Saxon and medieval smiths are unsurpassed by modern work.21 Pottery likewise early reached a high The methods of leather-working were in- herited direct from the ancient empires and remained little changed until well into the nineteenth The mining practice of Roman times was not greatly improved until the eighteenth century.% Wood- workers’ hand-tools remained much the same from about 500 A.D.; indeed those of an Egyptian car- penter of 1400 B.C.would be perfectly recognisable by his modern western ~ounterpart.~~ Building methods underwent no revolutionary change until the era of steel frames and concrete.26 The relations of techniques to science before the nineteenth century were evidently quite different from those to which we are now accustomed. The achievements of craftsmen that we have just noted owed nothing to science. The great agricultural l3 The literature on this subject is scanty. A recent article is one by Hoykaas Centaurus 1958 5 307-322.l4 HT Vol. I Chap. 21. l5 Charles Singer “The Earliest Chemical Industry,” Folio Society London 1948. lG HT Vol. 11 p. 380. HT Vol. XI pp. 744-745. 18 HT YO^. r p. 413. 19 HT Vol. I Chap. 29. HT Vol. I Chap. 23. 21 HT Vol. 11 Chap. 13. 22 H.T Vol. IT Chap. 8. 23 HT Vol. IT Chap. 5; cf. p. 753. 24 HT Vol. 11 Chap. 1; cf. p. 753. HT Vol. 11 p. 388 et seq. 26 HT Vol. T Chap. 17; Vol. 11 Chap. 12; Vol. 111 Chap. 10; Vol. IV Chap. 15. advances of the period 1770 to 1840 again were made independently of chemistry and soil science.27 Splendid buildings had for centuries been erected successfully without the aid of theoretical statics.28 The machines that revolutionised the cotton industry were the work of practical men not of scientists (though Watt’s improvements to the steam-engines which drove these machines had a scientific back- ground29).On the other hand there were some tech- niques which had been quite early influenced by science. Clocks had benefited from Huygen’s work on the pendulum in the seventeenth century,30 and navigation from the adoption of the magnetic com- pass in the thirteenth century and the later diffusion of astronomical knowledge and instrument^.^^ The chemical industry as we have seen began to make use of chemical science in the late eighteenth century. But these techniques were exceptional. Until the nineteenth century craft knowledge probably con- tributed far more to the basic data of science than it received in return.32 INDUSTRIAL REVOLUTIONS The West has seen several industrial revolutions each related to a new phase of me~hanisation.~~ In the ancient empires and in Greek and Roman civilisations the source of power was the muscles of men and of animals chiefly oxen.The use of horses for heavy work was retarded by an inefficient method of harnessing based on ignorance of the animal’s anatomy; a breast-band was used with the result that when the horse pulled hard a choking pressure was exerted on the wind-pipe. The modern harness with a padded collar was introduced in the early middle ages and became general in the twelfth century.= This increased the power of the horse to about 16 times that of a man and greatly improved medieval transport agriculture and industry the illustrations to Agricola’s “De re metallica” (1 556) show considerable use of horses as prime movers.Water-mills were rapidly developed and dis-seminated in the early Middle Ages-Domesday Book records about five thousand-and gave about 5 h.p. Windmills gave a comparable output and were widely used from the seventeenth century in suitable districts such as the Low Countries. These sources of power were dominant until the end of the eighteenth century and their capacity determined the 27 HT,Vol. IVY Chap. 1. 28 HT,Vol. IV p. 477 et seg. PROCEEDINGS range of machinery that could be used and therefore the processes and products. This helps to explain the remarkable continuity of craftsmanship until this period that we have already noted.The next revolution was due to the steam-engine. The Newcomen engine was coming into general use by about 1725 for pumping especially for mines and also for raising water for operating water-wheels to keep them independent of fluctuations in the flow of streams. But the application to manufacturing machinery was largely due to Boulton and Watt who during their partnership from 1775 to 1800 turned out some five hundred engines of which 308 were rotative engines and 164 pumping-engines. The great advantage of steam-engines at this stage was that besides being independent of flood drought and frost they could be used in any district where coal was available. But since they mostly developed only about 15 h.p.they did not eliminate the use of water-power; in 1815 Lancashire and the West Riding had 1,369 steam-engines and 866 water- wheels. The development of the steam-engine into a new and stronger prime mover came between 1800 and 1850 with the use of high-pressure steam which Watt had not employed because pistons and cylinders could not be made to fit properly until machine tools had been developed by Maudslay and his successors. While the steam-engine multiplied the power available machinery multiplied the operations that it could effect and extended its use from mines to textile mills breweries steel-works and so on. Directly related to these technical advances was the development of the factory system of production with all its social consequences-the concentration of the population into industrial towns the resulting problems of housing drainage water-supply and health services and the transformation of Britain from a rural community into a manufacturing and exporting nation in which the majority of citizens were dependent on employment for their livelihood and had no share in the ownership or control of the factories where they worked.Other sources of power appeared late in the nineteenth century ;the first power-station to supply electricity for street lighting and private consumers was opened in 1882 and the first small light petrol engine was patented by Daimler in 1885. But al- though these inventions have made available power 29 Watt’s engine was essentially a Newcomen engine modified by having a separate condenser to avoid loss of heat in the cylinder.In making this improvement Watt was aware of the importance of latent heat. 30 HT,VOl. 111 p. 344. 31 HT Vol. 111 Chaps. 19 and 20. 32 Cf. Dr. Hall’s estimate HT Vol. 111 p. 718. 33 HT Vol. 11 Chap. 17; Vol. IV Chaps. 5 6 7; Vol. V Chaps. 11-14 25. 34 HT Vol. 11 Chap. 15. JULY 1961 from small electric or petrol-driven units they have done little to reverse the trend towards large towns and factory production. Similarly atomic energy which offers a means of generating electricity without the use of coal is not revolutionary in the sense of producing power in greater quantity more cheaply or in a new form. Its main social significance appears to be that it will mark the end of the dependence of heavy industry on coal and will facilitate the intro- duction of mechanised industry to countries that lack coal-mine~.~~ EASTAND WEST IN THE HISTORY OF Whatever the opinion of Western culture held by men nurtured in the ancient Eastern civilisations- Islamic Indian Chinese-Western technology is acknowledged to be supreme.It was not always so. The technical knowledge of the Greek and Roman civilisations unlike their literature art and thought was not in most respects superior to that of the ancient empires of Mesopotamia and Egypt;37 this is Dr. Singer’s view and the evidence for it is to be found in the first two volumes of this “History.” After the fall of Rome until the thirteenth century the flow of technical knowledge was from east to west via Byzantium or Islam.A survey of the earliest uses of inventions in China and in Western Europe shows long time-lags between east and west often of many centuries; cases in point are printing navi- gation by compass and the military use of gun- powder-the three inventions which Francis Bacon declared to be decisive. By 1500 however the East had almost ceased to give ideas and techniques to the West and ever since has been receiving them. It is tempting to suggest reasons for this reversal or at least to list some relevant factors. (i) In classical antiquity in the west a sharp distinction was made between liberal arts and mechanical arts and a fatal separation developed between theory and practice; educated men came to despise the craftsman.Hero’s steam-engine for example was a mere toy and the water-mill though known to Roman engineers was not used by them to drive machines. Economic need made no impact on the ruling classes of Rome for slave labour was plentiful and cheap until the end of the third century. “Slavery depressed the social and economic condi- tions of the free craftsmen kept their wages low and subjected them to the contempt of the intellectual classes. Combined with restricted demand it had frustrated mechanical inventiveness and the organisa- tion of efficient methods of production of cheap goods for all . . .Only the Old Testament rose to the moral concept of the inherent brotherhood of man (Job xxxi 15) and to the denial of the right to own a man in perpetuity.In the classical world several schools of philosophers notably the Stoics preached this human brotherhood. . . .The advent of Christian- ity introduced a more basic concept for which the new term caritas (charity) was coined; this was more than mere friendliness and hospitality. Christianity not only changed the attitude of the citizen towards the poor and the slave; it radically attacked the classical views and extolled the value of manual labour. In this way slavery was doomed to disappear in the long run and the craftsmen were to gain an honourable place in society.”% (ii) In the medieval period Europe began with many additional advantage^.^^ It had great natural resources in water wood coal metals and other minerals.It had no excess of population. Its people were basically united in religion and educated men everywhere could communicate in a common language. There was no great barbarian invasion into the heart of Europe after the tenth century. These were conditions making for expansion. More- over Europe seems to have had a unique capacity for assimilation. Just as its characteristic view of life contained elements drawn from Greece Palestine and Rome so its technical borrowings extended to Islam India and China. (The West was well served by its translators.) Moreover these borrowings were efficiently exploited. Printing for instance was known much earlier in China but it was in Europe that full technical advantage was taken of the inven- tion of movable type which permitted thz rapid diffusion of knowledge.Medieval Europe so far from being backward and static as it is still some- times portrayed developed the technical bases from which later progress was made. (iii) In comparatively recent times technics has been controlled by science; and science began in the West. Science is not simply experience or observa- tion or experiment; it is dominated by its system of explanation. Thus technics has not the same aim or method as science though it has made great contri- butions to science in the shape of observations that require to be methodically investigated. However advanced technics does not lead to science unless the desire for scientific explanation is present.The mag- nificent techniques of medieval China for instance 35 On the effects of automation see N. Wiener “The Human Use of Human Beings,” Eyre & Spottiswoode London 1950. 36 HT Vol. 11 Chap. 17 (Professor Forbes) and Epilogue (Dr. Singer); Vol. 111 Epilogue (Dr. Hall). 37 The Far East is not treated in these volumes. This gap is partly filled by Dr. J. Needham’s volumes on “Science and Civilisation in China,” Cambridge Univ. Press 1954 1956. 38 HT Vol. 11 pp. 605-606. 3e HT,Vol. 111 Epilogue. PROCEEDINGS were developed empirically not scientifically and the explanations given for natural phenomena were of primitive types.40 Meanwhile however the begin- nings of scientific method were being worked out in Oxford Paris and Padua and the stage prepared for Galileo and for the great seventeenth-century advances which ultimately turned the scale in favour of the West.4l The decisive factor here seems to have been the interest in explanations of the scientific type; that is laws of nature and hypotheses from which they may be deduced.This is a specialised kind of explanation different from the kinds commonly used in human affairs and so in politics history and law where the relevant explanations of events are statements about human agents and their motives rather than scientific laws. Scientific explanation re- quires the presupposition of a law-abiding order in Nature; this is a conception foreign to primitive thought which tends to identify natural phenomena with capricious superhuman beings the deities of sea wind river sun moon and stars.That the principles of scientific explanation were gradually clarified and formulated in the west is probably due to the prolonged forging of the European tradition in Greek logic and mathematics in monotheistic religion (which eliminated the deities of primitive belief) and in the Roman sense of law-a three-fold tradition leading to an intellectual synthesis un- paralleled elsewhere and one that has been uniquely fruitful in science as in other branches of enquiry. TRIVIA Such volumes as these are delightful ragbags of miscellaneous knowledge. Among the pickings are the following. In ancient Sumeria workmen had a ration of beer of about a litre a day; officials of low rank had double higher officials (and the ladies of the court) treble and the highest functionaries about five lit re^.*^ The Colossus of Rhodes originally over 120 feet high buckled at the knees in an earthquake and spent nearly a millenium in a semi-collapsed state until the Saracens broke it up in 653.43 In classical times the streets of Tyre had a reputation for bad smells which were due to the decomposing bodies of the molluscs used to make the “imperial” purple dye (6,6’-dibrornoindig0).~~A “magnificent description of all the methods used in Bronze Age mining,” including fire-setting is to be found in the Book of Job chapter 28.45The problem of making a reliable clock was greatly complicated in the ancient world because it was required to show “temporal hours,” which were equal fractions of the hours of daylight and so varied from season to season.46 The Romans began to use window-glass in the first century A.D.though it was uncommon before the third century.47 Absolute alcohol was prepared in the thirteenth century by distillation from quicklime.@ Blast-furnaces with water-driven bellows came into use in the fourteenth century.49 In 1841 33% of the men and 44% of the women who married in England and Wales signed the marriage register with a mark.50 40 Cf. Needham “Science and Civilisation in China,” Vol. 11 Cambridge 1956. 41 Cf. A. C. Crombie “Augustine to Galileo,” 2nd edn. London Mercury 1961 ;“Robert Grossetests and Experi-mental Science,” Oxford Clarendon Press 1953.On the factors that favoured the origins of science in the West see A. N. Whitehead’s chapter “The origins of modem science” m “Science and the Modern World,” Cambridge 1926. 42 HT Vol. I p. 279. 43 HT Vol. 11 p. 470. 44 HT,Vol. I p. 247; Vol. 11 p. 367. 45 HT Vol. I pp. 564-565. 46 HT Vol. I p. 113;Vol. IT p. 602. 47 m,voi. In p. 237. 48 HT Vol. 11 p. 142. 49 HT,Vol. 11 p. 73. HT,Vol. V p. 776. COMMUNICATIONS The Irradiation of Unsaturated Sultones P. DE MAYO,A. B. M. ABDUSSATTAR, By E. HENMO and A. STOESSL (DEPARTMENT UNIVERSITY ONTARIO CANADA) OF CHEMISTRY OF WESTERN LONDON lRRADIATroN of systems (1) leads to open-chain reason to limit the number of heteroatoms intro- compounds.l In all cases so far reported the ring has duced.been carbocyclic or has contained one oxygen atom The sultone2 (11) on irradiation in methanol gave (Rand R’ = alkyl or acetyl X = 0;or CRR’ = the sulphonic ester (111). The structure of this sub- CO X = 0).There appeared however tQ be no stance followed from its hydrolysis to compound For a review see Mayo “Advances in Organic Chemistry,” Interseisnce Publ. Corpn. New York 1960 Vol. TI p. 367. Henmo Mayo and Stoessl unpublished work. JULY 1961 (IV) (together with 1 mol. of benzoic acid) further cleaved by ozonolysis and cyclised by warm alkali to the known phenalene derivative3 (V). Irradiation of the sultone4 (VI) gave the unstable ester (VII; X = Ph Ph SO Me Ph S0,Na &fJ -oa OMe) [2,4-dinitrophenylhydrazone,Amax.372 mp (E 22,000)] whose constitution follows from the close resemblance of its ultraviolet and infrared (c=oregion) spectra to those of mesityl oxide. The nuclear magnetic resonance spectrum* showed bands at = 7.91 and 7.81 (vinyl and terminal Me) 6.14 (OMe) 5.44 (cH~ and 3.68 (vinyl- hydrogen). The spectrum of the 2,4-dinitrophenyl- hydrazone showed (apart from bands due to aromatic hydrogen) bands at T = 7.75 and 7-80 (vinylic Me and terminal Me) 6.25 (OMe) 5-40 (CHd and 4.2 (vinyl-hydrogen). Irradiation of the sultone (VI) in ether containing two equivalents of benzylamine gave the amide (VII; X = NHCH,Ph) (and further transformation pro- ducts) characterised as the 2,4-dinitrophenyl-hydrazone Amax.375 mp (E 25,000) which (apart from bands due to aromatic hydrogen) showed bands at r = 7-81 and 7.66 (vinyl and terminal Me) 6-17 (ally1 CHd and an AB pattern with r = 5-61 and 5.16 (benzyl CH2and sulphonamide-hydrogen). In the irradiation of cyclohe~adienones~ (I; X = CO RR’ = H,AcO or H,alkyl) the unsaturated esters amides or acids obtained were postulated as being formed by way of ketens that may be produced by cleavage of the bond a to the carbonyl group followed by electron redistribution. A similar process invoked in cleavage of unsaturated sultones would require reversible formation of intermediates such as (VIII) containing the C=S02 grouping. Such sub-stances (which have been termed sulphens) have been sporadically invoked as intermediates,6 but no well-defined substance derived unambiguously from such a species appears to have been previously Obtained.The authors are indebted for financial support to the Imperial Oil Ltd. of Canada and to the U.S. Air Force mder Grant No. AF-AFOSR-61-6- They would like to thank Dr. J. B. Stothers for the deter- mination of the nuclear magnetic resonance spectra. (Received April 17th 1961 .) * Nuclear magnetic resonance spectra were recorded in carbon tetrachloride or deuterochloroform solution containing 1 % of tetramethylsilane by using a Varian V-4302 spectrometer; the peak positions were determined by means of an audio-oscillator calibrated with a Hewlett Packard 522-B counter. Koelsch and Rosenwald J.Amer. Chem. Soc. 1937 59 2166. Morel and Verkade Rec. Trav.chim.,1949 68 619. Barton and Quinkert J. 1960 1. Staudinger and Pfenniger Ber. 1916 49 1941; Zincke and Brune Bm. 1908 41 902; Zincke and Glahn Ber. 1907 40,3039. The Anodic Capacity of a Mercury Electrode in Aqueous Sodium Fluoride Solutions By M. J. AUSTINand ROGER PARSONS OF PHYSICAL CHEMISTRY BRISTOL) (DEPARTMENT AND INORGANIC THE UNIVERSITY WATTS-TOBIN~ recently discussed the explanation of the sharp increase of the capacity of a mercury electrode in contact with aqueous sodium fluoride which is observed2 when the potential is more than about 0.5 v positive of the point of zero charge. One possibility he considered was that this large capacity Watts-Tobin Phil.Mag.1961 61 133. a Grahame,J. Amer. Chem. Soc. 1954,76 4819. is due to the adsorption of hydroxyl ion. All Grahame’s measurements2 were made with pure sodium fluoride dissolved in water. Owing to hydrolysis these solutions will be slightly alkaline having a pH about 8.1 for the 0-lwsolution. As pointed out by Watts-Tobin the presence of spec4- fically adsorbed hydroxyl ions in this solution would readily be detected by making capacity measurements in fluoride solutions of different pH. We have carried out such measurements using a dropping-mercury electrode in a simple two-com- partment cell. The cell impedance was measured by using a symmetrical bridge with resistive ratio arms (Sullivan 0.1 %) and a decade condenser (Sullivan type C 868/2) and decade resistance (Sullivan type AC 1045) in series as the equivalent circuit.Alternat- ing and direct polarising potentials were applied between the junction of the ratio arms and the earth. The dropping electrode was earthed and a mercury pool used as a counter-electrode. The off-balance signal from the bridge was applied to the Y plates of an oscilloscope. The balance point was timed by the method described by Randle~.~ Mercury was twice distilled in a Hulett still. Twice recrystallised sodium fluoride was dissolved in twice distilled water. The results are shown in Figure. A small peak due to oxygen reduction was observed at a potential about -0.1 v on the normal calomel scale. At the same potential an increase of the series resistance was found.All points corresponding to this situation have been omitted from the Figure. Thus the points plotted are true double-layer capacities. The agree- ment with Grahame’s2 results is satisfactory for the pure O-lM-sodium fluoride. The pH was adjusted between 7 and 12 by the addition of small quantities of hydrogen fluoride or sodium hydroxide. It is evident that between pH 7 and pH 11 there is very little effect on the capacity even near the anodic limit of the curve. At a given capacity the potential ;hanges by at most 50 mv for this change of 4in the pH i.e. 12.5 mv/pH. Watts-Tobin suggests a prob- able minimum value of 120 mv/pH for this shift although the absolute minimum for his model is Randles Trans.Faraday Soc. 1954 50 1246. Oldfield Thesis London 1951. PROCEEDINGS 60 mv/pH. Hence it may be concluded that it is improbable that the anodic rise in the capacity in sodium fluoride solutions is due to the adsorption of hydroxyl ions. tl I I I I1 I I I 114 +0*4 0 -0.4 -08 -1.2 -1.6 Potential (volts) Diflerential capacity of a mercury electrode in aqueous O-lM-NaF with small quantities of HF or NaOH added. x pH = 7; * pH = 8; A,pH = 11; a pH = 12. Full line results of Grahame2 in pure aqueous 0.1 M-NaF. On the other hand there is a considerable shift in the anodic capacity curve between pH 11 and pH 12. This suggests that specific adsorption of hydroxyl ions becomes important as the concentration of hydroxyl ions exceeds about 1 mM.This conclusion differs from an earlier one4 made on the basis of measurements of the electrocapilIary curves of hydroxide solutions. Further work is therefore necessary to decide which interpretation of the results at pH > 11 is correct. (Received May 8th 1961.) Homolytic Aromatic Methylation By G. E. CORBETT (CHEMISTRY KING’S COLLEGE LONDON, DEPARTMENT STRAND W.C.2) and G. H. WILLIAMS DEPARTMENT COLLEGE LONDON, (CHEMISTRY BIRKBECK MALETSTREET W.C.1) METHYL radicals have been shown to be formed on photolysis of methylmercuric iodide. On photolysis of a solution of this reagent in isopropylbenzene 2,3-dimethyl-2,3-diphenylbutane (bicumyl) was formed in 66% yield with a nearly quantitative yield of methane. A boiling solution of methyl- mercuric iodide (3.43 g.0.01 mole) in isopropyl- benzene (200 ml.) which had previously been saturated with nitrogen was irradiated in a Pyrex flask until no more gas was evolved (about 3 hr.) with a Philips 300 w ultraviolet lamp (type 57265F/28) mounted as close as possible to the reaction vessel. When no more gas was evolved (about 3 hr.) ether and aqueous potassium iodide were added when the mercurous iodide formed was converted into metallic mercury and mercuric iodide the latter being removed as its solution in aqueous potassium iodide. The organic layer afforded JULY 1961 2,3-dimethyl-2,3-diphenylbutane(0-08g. 0.0033 mole) m.p. 118" and 230 ml. (1 3O/757 mm. ; 0.0091 mole) gas were evolved.2,3-Dimethy1-2,3-diphenyl-butane is known to be formed by the dimerisation of 2-phenyl-2-propyl radicals resulting from a-hydro- gen-abstraction from isopropylbenzene by free radicals (in this case methyl radicals formed by homolysis of the carbon-mercury bond in methyl- mercuric iodide) hv MeHgl -f Me-+ Hgl. PhCHMe + Me--f CH $-PhCMe,. ZPhCMe,. PhCMe,CMe,-Ph -f In similar reactions conducted in the dark and under illumination by a 150 w tungsten-filament lamp no observable decomposition of the methyl- mercuric iodide occurred. Thus the decomposition is photolytic and radiation of about 3030-40oO A wavelength effects it. This reaction of methylmercuric iodide is therefore closely analogous to the photo- lysis of phenylmercuric iodide which gives phenyl radica1s.l Replacement of nuclear hydrogen atoms by methyl radicals formed in this way occurred when solutions of methylmercuric iodide in benzene and in chlorobenzene were subjected to photolysis for 1-6 hr.as described above. A quantity of methane equivalent to about half of the total available methyl radicals was also formed. The following mechanism Hey Shingleton and Williams unpublished work. Chang Shih Hey and Williams J. 1959 1871. Cowley Norman and Waters J. 1959 1799. 24 1 which is similar to that of phenylation of aromatic compounds by phenyl radicals,2 is therefore a reasonable working hypothesis ArH + Me. -> [AiH \Me 1. [.r/" 1.+ Me. -f ArMe + CH, \Me Thus the maximum yield of methylation products in this reaction is 0.5 mole per mole of methylmer- curic iodide and the yields given below are cal- culated on this basis.Methylation of benzene by this method gave toluene in 62% yield and that of chlorobenzene a mixture of u- rn- and p-chloro- toluenes in 54%yield. The composition of this mix- ture was found by infrared spectrography to be ortho 62.0; meta 28-4;para 9.6%. This distribution of isomers is close to that obtained by Cowley Norman and Waters3 in the methylation of chloro- benzene with methyl radicals formed by thermal decomposition of t-butyl peroxide although this method generally gives poorer yields than are obtained by the photolysis of methylmercuric iodide. We thank the Distillers' Company Ltd. and King's College London for grants (to G.E.C.).This work was done with the support of the National Research Development Corporation. (Received April 25th 1961.) Racemization and Radio-chloride Exchange of p-Chlorobenzhydryl Chloride with Mercuric Chloride By A. LEDWITH,* M. HOJO,and S. WINSTEIN (CHEMISTRY DEPARTMENT CALIFORNIA) UNIVERSITY OF CALIFORNIA LOS ANGELES FIRST-ORDER racemization rate constants (k,) of benzhydryl-type chlorides are substantially greater than first-order solvolysis (kt) or radio-chloride exchange(ke)rate constants in a variety of in the presence of lithium or tetra-alkylammonium chlorides. Intermediate carbonium chloride ion pairs become racemic and return to optically inactive co- valent chloride more rapidly than they dissociate are solvolyzed or exchange their anion partner with external chloride ion.We now report the dramatic and instructive change in the (k,/ke) ratio for p-chlorobenzhydryl chloride in anhydrous acetone2 which is produced by the substitution of the electro- philic catalyst mercuric ~hloride,~for lithium chloride or tetrabutylammonium chloride. In the presence of mercuric chloride k and ke for p-chlorobenzhydryl chloride in acetone are both in-creased enormously rates being conveniently followed at 25" instead of 75" in the case2 of lithium or tetrabutylammonium chloride. Whereas k is estimated to be 3 x loL9sec.-l at 25" in the absence of added salt it is 1.90 x lo-* sec.-l in the presence of lop2M-mercuric chloride.For mercuric chloride concentrations of 1-15 x M plots of * On leave of absence from the Department of Inorganic and Physical Chemistry University of Liverpool. Winstein Gall Hojo and Smith J. Arner. Chem. SOC.,1960 82 1010; Winstein Hojo and Smith Tetrahedron Lrtters 1960 No. 22 12; Pocker Pruc. Chem. Soc. 1961 140. Winstein and Gall Tetrahedron Letters 1960 No. 2 31 ;Winstein Ledwith and Hojo ibid.,in the press. See e.g. Bodendorf and Bohme Anna!eii 1935 516 1 ; Read and Taylor J. 1940 679. k and ke are accurately linear in [HgCl,] and lead to second-order rate constants of 1-87 x lo- 1. mole-l sec.-l for racemization and 1.24 x lo- 1. mole-' sec.-l for radio-chloride exchange at 25.0". Over the whole range of [HgCl,] investigated the (k,/ke)ratio is (1 -50 f0-03).It seems clear that racemization and radio-chloride exchange proceed by HgCl,-assisted ionization3 of RCl to R+HgCl,-. For return of ionic intermediates to racemic RCI one may plausibly anticipate that the chance for radio-chlorideexchange to occur is in the range from 2 3 to 1 1. For return with retention of configuration the chance for exchange to occur could conceivably be zero 1 :2 2:3 or even 1 1 (if the HgCl,-group of the R+HgCl,-pair exchanges chloride with other labelled HgCI molecules). PROCEEDINGS It does not seem likely that the exact 2:3 ke:k ratio which is observed is the result of a coincidental blend of different exchange:racemization ratios out-lined above. One may instead visualize that the 2:3 ratio arises because all exchange occurs by regenera-tion of RCl from R+HgCI,-pairs which have become racemic and have also lost all distinction between the three chlorine atoms but are still so constituted that two chlorine atoms are from the original labelled HgCl and one is from the RCl.We are indebted to Dr. C. A. Bunton for helpful discussions. This research was supported by the National Science Foundation. (Received June 8th 1961.) Basic Beryllium Nitrate By C. C. ADDISON and A. WALKER (DEPARTMENT THEUNIVERSITY, OF CHEMISTRY NOTTINGHAM) THEREare four possible ways in which the nitrate group could bond covalently to metal atoms namely as a unidentate a bidentate or a tridentate Iigand to one metal atom or as a bridge group between two metal atoms.A compound in which the particular type of bonding is known becomes a key compound in this field since the characteristic pro-perties (especially the infrared spectrum) can then be identified. Basic beryllium nitrate is believed to be the first example of a compound in which the nitrate group acts as a bridge group within a single molecule and it shows this feature to a remarkable extent. Beryllium chloride undergoes solvolysis in ethyl acetatedinitrogen tetroxide mixtures to give pale-straw crystals of the addition compound Be(N0,),,2N,04. When heated in a vacuum this decomposes in two stages. Dinitrogen tetroxide is evolved rapidly above 50°,leaving anhydrous beryl-lium nitrate Be(NO,), as a white powder which has no detectable volatility.This is stable to about 125" then sudden decomposition occurs to give dinitrogen tetroxide and a volatile beryllium compound which separates from the gas phase as colourless crystals. Analyses correspond with the formula Be,O(NO,) [Found Be 8.5 N 19-5. Calc. for Be,O(NO,), Be 8.5; N. 19.8%]. The compound dissociates in solution in dilute aqueous sodium hydroxide; the ultraviolet spectrum of this solution indicates that six nitrate ions are produced from one molecule of the compound and confirms the absence of nitrite. There is an obvious analogy with basic beryllium acetate Be,O(OAc), and the basic nitrate is believed to possess the structure shown in the Figure. The outer sphere of oxygen atoms will carry a larger charge than will the methyl groups which occupy these positions in the basic acetate.In consequence the basic acetate is soluble but the basic nitrate is insoluble in non-polar solvents such as chloroform benzene and carbon tetrachloride. An X-ray crystal- lographic study by s. C. Wallwork and B. Duffin is 0 Basic beryllium nitrate. in progress in these laboratories. The basic nitrate crystallisesin a cubic unit cell of side 14.04 f0.02A and density 2-05 rt 0.01 g./cm.,. The molecular weight of the cell contents is therefore 3418 f23 which is consistent with eight molecules of formula Be,O(NO& (M,424) in the unit cell. The infrared spectrum of the compound and its properties in solution and in the gas phase are being investigated.We thank D.S.I.R. for a maintenance grant (to A.W.) and the U.S. Department of the Army for financial support. (Received May 17fh 1961 .) JULY 1961 243 Biosynthesis in the Amaryllidaceae:Incorporation of Norbelladhe into Lycorhe and Norpluvine By A. R. BATTERSBY, R. BINKS,and S. W. BREUER (THEUNIVERSITY, BRISTOL) and H. M. FALES and W. C. WLLDMAN (NATIONAL OF HEALTH U.S.A.) INSTITUTES BETHESDA IThas been establishedfp2 that [2-14C]tyrosine (I; R = C02H) is incorporated into lycorine (III). Also since the activity of the labelled alkaloid is located entirely at the position marked with an asterisk,l it follows that tyrosine can provide that part of the molecule drawn with heavy bonds.[2-14C]Tyrosine was also shown1 to be incorporated into norpluvine (IV) (0-15 % incorporation). These results are in keep- ing with the proposal3 that the biosynthesis of the Amaryllidaceae alkaloids involves oxidative coupling of phenolic intermediates such as (II;R = H or OH) or simple methylation products of these systems. In order to study further the later stages in the biosyn- thesis norbelladine (11; R = H) labelled in the carbon skeleton has been synthesised. The incorpora- tion of activity into galanthamine from an [W4C- methyl] derivative of the phenol (11; R = H) has been recorded.2 [l-14C]Tyramine (I; R = H) was treated with 3,4dihydroxybenzaldehyde and the resultant imine was reduced catalytically over paladium. Fractiona-tion of the products on buffered alumina gave norbel- ladine (11; R = H) which was assayed for activity as its crystalline picrate.This product was shown to be pure and in particular to be free from tyramine (I; R = H) by taking radioautographs of partition chromatograms. The labelled norbelladine was fed to double Narcissus plants (variety “Twink”) which were har- vested one month later. Isolation of the alkaloids as earlier,l yielded radioactive lycorine (III) and nor- pluvine (IV) (0.24 % and 0.74% incorporation respectively). The lower incorporation of activity from norbelladine into lycorine (UI) than into nor- pluvine (IV) is not unexpected and this aspect is being studied further. The incorporation into nor- pluvine from norbelladine (11; R = H) is much higher than it was from tyrosine suggesting that norbelladine (11; R = H) stands the closer to norpluvine (IV) on the biosynthetic pathway.The radioactive lycorine was degraded as in our earlier workf to the lactam acid (V) and formalde- hyde (isolated as the dimedone derivative) whose 096*C (v) o.oo*c relative activities are shown in the chart (the inter- mediate degradation products1 had the same activity as lycorine within the limits of experimental error). Thus all the activity of lycorine (HI) is located at the position marked with an asterisk further supporting the view3 that phenolic coupling is an important step in the biosynthesis of the Amaryllidaceae alkaloids. Additional evidence is being sought by degradation of the radioactive norpluvine (IV).We thank the Rockefeller Foundation for financial support. (Received May 1Sth 1961.) Battersby Binks and Wildman Proc. Chem. Soc. 1960 410. a Barton and Kirby Proc. Chem. SOC.,1960 392. a Barton and Cohen “Festschrift Arthur Stoll,” Birkhauser Verlag Basle 1957 p. 117. PROCEEDINGS Excited Chloroethyl Radicals C2H,Cl,-,* By P. B. AYSCOUGH F. S. DAINTON, A. J. COCKER S. HIRST and M. WESTON (DEPARTMENT CHEMISTRY,THEUNIVERSITY, OF PHYSICAL LEEDS 2) WITHthe exception of vinylidene chloride which has of both cis-and trans-l,2-dichloroethyleneare not yet been investigated several features of the accompanied by geometrical isomerisation far too kinetics of the homogeneous photochlorination of rapid to be accountable in terms of reaction (-2) the gaseous chlorinated olefin C,H,Cl,- (A) can be and having rates Ri such that Ri = Rp(B + C/[Cl,]) interpreted in terms of the reaction mechanism where B and C are almost temperature-independent.Secondly at low pressures of A the dependence of CI + hv 3 2CI ... (11 R on [Cl,] for vinyl chloride and cis-1,2-dichloro- CI + A +ACI ... (2) ACI + CI -+ACI + CI . . . (3) ethylene is given by R = D[Cl,]/( 1 + E[Cl,]} and 2ACI -+A,CI or A + ACI ... (4) the magnitudes of D and E are quite incompatible ACI + CI -f ACI or A + CI ... (5) with the known values of k, k, and the maximum 2CI + M -f CI + M ... (6) probable value of k-,. Thirdly competitive photo- Above a lower limiting concentration of olefin chlorination in mixtures of cis-1 ,Zdichloroethylene characteristic of each individual olefin the rate Rp = and C,H3Cl indicate that a rapid reversal of reaction d[ACl,]/dt obeys the law Rp = k3[C12](21a/k4)* (2) occurs during photochlorination of C,H,Cl.and the rotating-sector technique has been applied These anomalies vanish and a self-consistent to obtain the tabulated Arrhenius parameters of photochlorination mechanism embracing all the reactions (3) and (4) for A = C,H,Cl cis-(CHCl), kinetic phenomena is attained if it be admitted that C,HCl, and C2C14. At very low concentrations the ACl radical initially formed in reaction (2) which A log10 A J5.2 log10 A E3 lo,o, A E4 x Y 1O3k,Kk + kr) k,/k, CH :CHCl 9.5 1.0 8.8 0.9 9.9 0.3 -1.7 -cis-(CHCl) 9.4 0.9 8.8 2.7 10.6 0.5 0.75 0-58 1.1 0.43 -C,HCl 9.6 0.7 8-5 5.1 9.5 0.5 -0.9 c2c14 9-6 0 8.3 5.5 8.7 0.1 -A values in 1.mole-' set.-' E values in kcal. mole-'; x and y are fractions of trans-(CHCl),emerging from processes a and /I,respectively; for source of data see ref. 4. of A and high chlorine concentrations RP = is vibrationally excited to an extent = DA...Cl+ E, k2[A](21a/k,[M])* and the rotating-sector method may react in four ways (a) decompose to A + Cl then permits evaluation of the Arrhenius parameters without further activation; (p)lose a chlorine atom of reactions (2) and (6). The results for cis-1,2- to a C1 molecule; (y) be deactivated rather efficiently dichloroethylene are shown in the Table. by chlorine molecules; and (8) either transfer a It would be expected that A_ z 1013 sec.-l and chlorine atom to A or be inert to A.Reactions a and E- 2 Da...cl,and Howlett's dehydrochlorination /3 are both routes for geometrical isomerisation. studies1 have suggested that for ACl = C,H,C12 Analysis of our data on this basis yields ratios of A_ :lo1 sec.-l and E- = 22 kcal. mole-I. These k,:kg:k given in the Table and the proportions of results taken with the probable variation of DA...Cl cis-and trans-(CHCl) obtained from C2H2C13* in from -17 to 23 kcal. mole-l as x varies from 1 to 4 reactions 01 and 8.The relative insensitivity of these and the tabulated values cf A and E3 indicate that quantities to change of temperature is strong con- at chlorine pressures of 50 mm. Hg reaction (-2) firmation of the view that excited chloroethyl radicals will always be negligible in comparison with reaction ACP are involved in these reactions.Convincing (3) at temperatures < 150"~.The data of Adam evidence for vibrationally excited reaction inter- Goldfinger and Gosselain for the photochlorina- mediates formed by the addition to alkenes of a exp. (-16,800/ hydrogen atom an oxygen atom or a methylene tion of C,Cl, for which k- = 1012-8 RT)will be the largest in the series fully confirm this. molecule has recently been obtained in several other However three observations are in striking conflict lab~ratories.~ with this simple picture. First the photochlorinations (Received April 17th 1961.) 'Howlett. Trans. Faradav SOC.. 1952. 48. 25. 2Adam Goldfinger. and Gosselain B~ll.~Soc.chim. belges 1956 65 549. Turner and Cvetanovid Cunad.J. Chem. 1959 37 1075; Cvetanovik ibid. 1958 36 623; 1959 37 953; Anet, Bader and Van der Auwera J. Ainer. Chem. SOC.,1960 82 3217. All the tabulated data for C,H,Cl and cis-(CHC1)2 and A* E,. and k,/(kp + k,) values for C,HCI are based on work in these laboratories. AS,E3. and E4 for C,HCI are taken from Dainton Lomax and Weston (Trans. Furuday SOC.,1957 53,460). Values for C,Cl are taken from Dusoliel Goldfinger Huybrechts Martens Smoes (Mme.) Van der Auwera and Van der Auwera's final technical report (December 1959) to U.S. Army under contract DA-91-591- EUC-994-01-111859. JULY 1961 245 Use of Magnesium Compounds in Some New Procedures for the Alkylation of Aromatic Hydrahns By E.T. BLUES and D. BRYCE-S~H (THEUNIVERSITY, READING) MAGNESIUM halides are normally only slightly active as Friedel-Crafts alkylation cata1ysts.l We now report some new alkylation procedures which appear to involve forms of magnesium halides having high catalytic activity. First we have observed that when an excess of an aromatic hydrocarbon is treated at ca. 100" with an n-alkyl chloride (1 mol.) magnesium (0-5 g.-atom) and an alcohol such as propan-2-01 or 2-methoxy- ethanol (0~005-0~05 mol. depending on the purity and physical state* of the reagents) alkylatioii (cf. ref. 1) occurs much more rapidly than if the alcohol is omitted. Thus butyl- and dibutyl-toluenes (65 % and 6% respectively) were obtained in 11 min. as mixtures of nuclear and side-chain isomers from toluene and n-butyl chloride butane (24%) and hydrogen chloride (48 %) were evolved in succession.The use of higher proportions of an alcohol or alkoxide is known to give alkylmagnesium chloride- alkoxide complexes.2 As organomagnesium compounds appeared to be intermediates in this reaction we investigated the production of magnesium halides in some Wurtz- type reactions. n-Butyl-and phenyl-magnesium cornpo~nds,1-~ when freshly prepared have been found to react readily at ca. 20" with hydrogen Chloride hydrogen bromide bromine s-or t-butyl chloride benzyl chloride or carbon tetrachloride. The products obtained in aromatic hydrocarbon media have formed insoluble solids varying in colour from purple to brown; but n-butylmagnesium chloride and an excess of hydrogen chloride in deca- hydronaphthalene at 0" have given an almost colour- less solid (Found Mg 26.15; Cl 70.8 total 96-95 %; atomic ratio Cl Mg = 1-85).Both the coloured and the colourless form react violently with water to give an alkaline solution with evolution of a little hydrogen. These substances are catalysts for the alkylation of aromatic hydrocarbons by alky1 chlorides and in the presence of a little hydrogen chloride by propene and but-1-ene. The catalytic activity appears to be comparable with that of aluminium or beryllium chloride. The most active materials have contained only chlorine as the halogen and for the highest activity it appears prefer- able to prepare the catalyst directly in the hydro- carbon which is to be alkylated.Ether traces of water or heating at 100-1 50" cause deactivation. For t-butylation t-butyl chloride has conveniently served both as catalyst precursor and as alkylating agent. Thus addition of n-butylmagnesium chloride (0-0005equiv. based on C-Mg) to a mixture of t-butyl chloride (0.1 mole) and benzene (0.45 mole) led within 13 minutes at 30" to the production of hydrogen chloride (90.5 %) t-butylbenzene (26 %) and di-t-butylbenzenes (62 %). t-Butyltoluenes (90 %) were similarly obtained :under anhydrous conditions the p:m ratio was 0.64,and no dialkylation was detected. These catalysts rapidly polymerised styrene and isoprene at room temperature. Ordinary magnesium chloride was ineffective.The mechanisms of the alkylations and the structures of the catalysts are under investigation. We thank Mr. Choufoer and his colleagues for repeating some of these alkylations and investigating some of the products by gas chromatography. (Received February 13th 1961.) * Freshly ground "Grade 4" pure powder (Magnesium Elektron Ltd.) is preferable to the usual turnings both for alkylation and in the related organomagnesium synthesis.2 Bryce-Smith and Owen J. 1960 3319. Blues and Bryce-Smith Chenz. aizd Ind. 1960 1533. Bryce-Smith and Cox J. 1958 1050; 1961 1175. A New Synthesis of Acetylenic Bonds and its Biosynthetic Implications By IANFLEMING and JOHNHARLEY-MASON (UNIVERSITY LABORATORY, CHEMICAL CAMBRIDGE) TREATMENT the sodiuni derivative of diethyl of benzoylmalonate with p-bromobenzenesulphonyl chloride gives the enol bromobenzenesulphonate (I) m.p.91-91 -5'. This on treatment with 0.2~-sodium hydroxide in aqueous dioxan at room temperature for 12 hours gives phenylpropiolic acid identified by comparison with an authentic sample isolated in 70-75 % yield after acidification. We regard this reaction as a concerted elimination-decarboxylation of the intermediate anion (11) as shown and this appears to provide one of the mildest known methods for making an acetylenic bond. One factor which may contribute to the unusual ease of triple-bond formation in this case is that a large entropy change is involved since the intermediate (11) falls apart to give three stable fragments.Acylmalonic esters are in general readily obtainable and extensions of this new synthetic method particularly in the direction of conjugated systems are in progress. Chem. and Eng. News 1961 39 No. 12,46. PROCEEDINGS In a recent lecture,I E. R. H. Jones has suggested the mechanism shown below as a possible route for the biosynthesis of acetylenic bonds CO H Acetyl-CoA t Malonyl-CoA -CH;CO-CH It will at once be seen that the reaction we now report and that proposed for the biosynthesis are formally extremely similar though different leaving groups are involved. We regard our observations as supporting Professor Jones's biosynthetic hypothesis. (Received May 1 1 th 1961.) The Addition of Carbenes to Ailenes By W.J. BALLand S. R. LANDOR (WOOLWICH POLYTECHNIC, LONDON,S.E.18) RECENTwork1 has shown that dichloro-and dibromo-carbenes add to 1,3-dienes (I) to give vinylcyclopropane derivatives (11; R = H or Me cx\* (I) CH,=CR-CH=CH H2C-CR-CH=U-I UO X = C1 or Br) only. We have found that dibromo- carbene adds similarly to 1,Zdienes (111) to give rnethylenecyclopropane derivatives (IV) in 40-60 % hydrogen. Superimposable infrared spectra were obtained for (i) 1,l -dibromo-2,2,3-trimethylcyclo-propane synthesised from 2-methylbut-2-ene and CBs R\ R" R\ -c=c /R" (IV) R'.c / \ on) R*,c=c=c H H dibromocarbene and (ii) the product of hydrogena-tion of compound (IV; R = R = Me R" = H). The addition of carbenes to allenes therefore opens Properties of compounds (IV).R R' R" B.p./mm. Me Et Pr Me Me Me H Me H H H Me 374"/1-7 46-49"/1.7 44-50"/3-5 39-40"/4 yield addition always being at the more substituted double bond.2 The products (see Table) which gave one band only in vapour-phase chromatograms gave infrared bands characteristic for the methylenecyclo- propane system and no ultraviolet absorption maxima gave formaldehyde (acetaldehyde where R = Me) on ozonolysis and absorbed one mol. of I.R. bands (cm.-') 1750w 1040s 905s 800s 1750w 1010s 900s 800s 1750~ 1070s 900s 795s 1750m 1000s 840m 730s a new route to the methylenecyclopropane system which is not readily accessible by other methods. We thank the Chemical Society for a grant for chemicals and the D.S.I.R.for a maintenance grant to W.J.B. (Received June 9th 1961.) Woodworth and Skell J. Amer. Chem. SOC., 1957,79 2542; Shono and Oda J. Chem. SOC.Japan 1959,80 1200; Ledwith and Bell Chem. and Ind. 1959,459. Cf. Skell and Gamer J. Amer. Chem. SOC.,1956,78 5430. JULY 1961 247 Electron-spin Resonance Spectra of Alkyl Radicals in y-Irradiated Alkyl Halides* By P. €3. AYSCOUGH and C. THOMSON (DEPARTMENT CHEMISTRY LEEDS,2) OF PHYSICAL THE UNIVERSITY DESPITE the widespread use of electron-spin reso- nance spectra for the identification of paramagnetic intermediates trapped in irradiated solids little is known of the hyperfine spectra of simple aliphatic radicals such as R.CH,-CH,. RRCHCH,. RCH,CHMe- and RCH,kHCH,R' which are believed to be present in irradiated hydrocarbons and polymers.There is much evidence from product analysis1 and from the use of I3lI tracers2 to suggest that alkyl radicals are the main thermalised inter- mediates in the radiolysis of liquid alkyl halides and we have shown by examining the electron-spin resonance spectra of y-irradiated samples that parent alkyl radicals are the main species trapped at -196". Apart from differences in line width the hyperfine spectra observed after irradiation depend on the number and relative orientation of the a-and /%protons of the alkyl fragment only and are inde pendent of the nature of the attached group R and of the halogen atom in the starting material. Thus the spectra of irradiated n-propyl chloride bromide and iodide are the same as those observed from n-butyl n-pentyl and isopentyl halides and may be attributed to RCH,CH,.radicals. Six hyperfine lines are observed with relative intensities approxi- mately 1:3:4:4:3:1 (see Figure) which is charac- teristic of the interaction of three equivalent protons and one with a hyperfine splitting approximately twice as great as each of the others. The hyperfine spectrum of y-irradiated CH,CD,.CH,Br is a triplet with relative intensities 1:2 :1 while. that observed in CH,.CH,CD,Br consists of four lines of equal size showing that the odd proton is in the p-position. (The line width is about 10 gauss so the deuterium splitting is not resolved.) From these spectra the hyperfine splitting constants for the a-and #?-protons are estimated to be a(a-H) = 24 a(/&H) = 46 a(#3,-H) = 25 gauss and spectra computed on this basis for the four interacting protons in n-propyl agree very closely with the observed six-line spectra.A similar interpretation is possible for spectra attributed to radicals of the type RR'CHCH,. which consist of five lines of relative intensities 1:2 :2 :2 1 and RCH,CHMe- which show eight lines (approximately 1:5 :1 1 :15:15:11 :5 :1). In both cases one /3-proton interacts with the unpaired electron to cause a splitting of 45 gauss the other interacting protons have splitting constants of about 25 gauss. ~ gauss Spectruniof n-propyl bromides y-irradiated at -196" (a) CH,CH,CH,Br (b) CH,CD,CH,Br (c) CH,CH,-CD,Br.Spectra derived from species in which the inter- acting nuclei are (-CH,),CH. are more variable. For instance the radicals derived from 3-bromopentane and from cyclopentyl bromide give eight-line spectra (approximately 1:3:5:7:7:5:3:1) showing that two p-protons cause a large splitting (45 gauss) while the other three protons each cause a smaller splitting of 25 gauss. The radical derived from cyclohexyl iodide (and from cyclohexane3) shows a spectrum which can be interpreted only in terms of two splittings of 45 gauss and one of 25 gauss; two of the protons there- fore interact too weakly to produce resolved structure. All these results can be explained in terms of the relative orientation of the P-GH bond and the p-orbital of the unpaired electron.It has been shown by examination of the spectra of irradiated single crystals of carboxylic acids et~.,~ that the isotropic hyperfine splitting of a p-proton is a function of the unpaired spin density at the position of the proton. This varies as cos28 where 8 is the angular displace- ment from the perpendicular to the nodal plane of the p-orbital and values of a(P-H) from about 3-45 * Presented at a meeting of the British Radiofrequency Spectroscopy Group at St. Andrews on April 6th 1961. See also a paper by Cochran Adrian and Bowers (J. Chem. Phys. 1961 34 1161). Dismukes and Wilcox Radiation Res. 1959 10 112; Wilcox ibid. 1959 11 754. Gevantman and Williams jun. J.Php. Chem. 1952,56 569; Schuler and Petry. J. Amer. Chem. SOC.,1956 78 3954. Smaller and Matheson J. Chem. Phys. 1958 28 1169. Heller and McConnell J. Chem. Phys. 1960 32 1535. gauss (8-126. Mc./sec.) have been ob~erved.~ On this basis we estimate that the p-protons in the radicals observed are in a relatively fixed orientation displaced about 15" from one or other of the two symmetric positions with respect to the p-orbital of the unpaired electron. WhXen personal communication. PROCEEDINGS We are indebted to Professor F. S. Dainton F.R.S. for the use of the radiation facilities of the Cookridge Laboratories including the 6oCosource presented by the Rockefeller Foundation and to D.S.I.R. for research grants. (Received May Sth 1961.) A Novel Elimination Reaction By W.PATERSON and G. R. PROCTOR THEROYAL OF SCIENCE GLASGOW) COLLEGE AND TECHNOLOGY, (CHEMISTRY DEPARTMENT THEformation of olefins by base-catalysed elimina- tion is well known? weak bases suffice when an efficient leaving group such as toluene-p-sulphonyl- oxy is employed.2 When alkaline hydrolysis of benzylsulphonamides was found to give benzalde- hyde presumably by hydrolysis of the intermediate SchWs bases Fenton and Ingold* recognised that the toluene-p-sulphonyl group might be made to leave the nitrogen atom of the amide (I; R = H) giving 1H-isoindole. Their experiments however which involved drastic conditions (e.g. fusion with potassium hydroxide) gave isoindoline. We recently used a base-catalysed elimination to convert the amide (11) into the azacycloheptatrienone (III).5 The conditions were not excessively vigorous but the a-carbon atom (with respect to nitrogen) is activated by a carbonyl group which presumably facilitates formation of the intermediate anion.We are studying this reaction as a preparative method for Schiff's bases and hope to apply it for introducing new C-N linkages. Some examples of the formation of new C-C bonds by similar processes have been reported6*' lately. The toluene-p-sulphonyl derivative (IV) treated with sodium ethoxide in toluene at room temperature gave phenylglyoxal and m.p. 210" in 95% yield. This was converted by palladised charcoal* into the isomer m.p. 145" obtained in very poor yield by direct condensation of phenylglyoxal and aniline.Loudon and Wellingslo studied the reaction of alkoxide on the amide (IV) in ethanol but did not isolate the anil. Takatall investigated several sulphonamides but examined only the sulphinic acids obtained. ,N-soi C~H~M~ Ph It appears that the elimination is well suited for the production of anils in which an activating car- bony1 group is present. As expected activation by a benzene nucleus is less powerful thus the sul- phonamide (V; R' = H) was recovered unchanged after 2 hours' treatment with sodium methoxide in toluene at 95" at 120" it decomposed. On the other hand the introduction of a p-nitro-group (V; R' = p-NO,J increases the activation to the extent that a good yield of p-nitrobenzaldehyde anil was obtained Ingold "Structure and Mechanism in Organic Chemistry," 1952 pp.420 et seq. Collins J. 1960 2053. Holmes and Ingold J. 1926 1305. Fenton and Ingold J. 1928 3295. Proctor Chem. and Znd. 1960,408. Barner Dreiding and Schmid Chem. and Id.,1958 1437. Winstein and Baird J. Amer. Chem. SOC., 1957 79 756. Paterson and Proctor Chem. and Ind. 1961 254. Yates J. Amer. Chem. SOC.,1952,74 5380. lo Loudon and Wellings J. 1959 1780. l1 Takata J. Pharm. SOC.Japan 1951,71 1474. JULY 1961 at room temperature. This suggests that a 2H-isoindole might be obtained from a compound (I; R = electron-withdrawing group) under mild conditions. 249 We thank Professor P. L. Pauson for helpful discussion and the Department of Scientific and Industrial Research for a grant to (W.P.).(Received,June 13th 1961.) The t-Butoxy-group A Novel Hydroxyl-protecting Group for Use in Peptide Synthesis with Hydroxy-amino-acids By H. C. BEYERMAN and J. S. BONTEKOE (LABORATORY HOGESCHOOL, OF ORGANIC CHEMISTRY TECHNISCHE DELFT NETHERLANDS) WE have found a novel way of protecting the hydroxyl group in the synthesis of peptides contain- ing hydroxy-amino-acids by making use of the t-butoxy-group. This may remain attached to the amino-acid or the peptide while the peptide bond is being established but it can be readily split by means of acid without fission of the peptide bond. As appears from our experiments with derivatives of L-serine L-threonine and L-tyrosine the optical activity is completely maintained during such a process; this was not unexpected even for threonine where the hydroxyl group is attached to an asym- metric carbon atom since it is known not only that The t-butyl ester of the N-benzyloxycarbonyl t-butoxy-L-amino-acid was obtained in about 90% yield.The benzyloxycarbony1 group was then removed by hydrogenolysis in the usual way with -100% yield. The products were characterised as crystalline derivative (a few details are listed in the Table). The two protective groups were removed simul- taneously by dissolving the compounds at or below room temperature in anhydrous trifluoroacetic acid giving pure L-amino-acids with correct optical rotations. The suitability of our method in peptide synthesis M.p.[a],in HCO.NMe O-t-Butyl-L-serine t-butyl ester hydrochloride 170" -6" (C 1.15) O-t-Butyl-L-threonine t-butyl ester picrate 140 -6" (C 2.10) O-t-Butyl-L-tyrosine t-butyl ester hydrochloride 154-1 55 +42" (c 1.75) t-butyl ethers are in general hydrolysed by acids under mild conditions but also by fission of the O-t-Bu b0nd.l The t-butoxy-group is conveniently introduced by acid-catalysed addition of isobutene to the hydroxyl group of N-acylated hydroxy-L-amino-acids dis- solved or suspended in an inert solvent; t-butyl esters of N-acyl-t-butoxy-L-amino-acids are thus obtained. It was already known2s3 that amino-acids whether N-acylated or not yield t-butyl esters in this way but it was not known that from the hydroxy-L- amino-acids the t-butyl ethers may be formed at the same time.Our procedure with serine threonine and tyrosine was as follows. The N-benzyloxycarbonyl- L-amino-acid was suspended in methylene chloride and a large excess (e.g. ten-fold by weight) of liquid isobutene was added. After addition of only a small amount of concentrated sulphuric acid the mixture was shaken at room temperature in a pressure flask until a clear solution had been formed (usually 6-10 hours). is demonstrated by the preparation of the C-terminal dipeptide of the pancreatic hormone gl~cagon,~ L-asparaginyl-L-threonine. Interaction of N-benzyl-oxycarbonyl-L-asparaginep-nitrophenyl ester5 and O-t-butyl-L-threonine t-butyl ester in dimethyl-formamide gave the analytically pure protected dipeptide (97%) m.p.114" [cc] -2" (c. 2-60 in dimethylformamide). Hydrogenolysis yielded pure L-asparaginyl-O-t-butyl-L-threonine t-butyl ester (98%) m.p. 149" [cc] + 3" (c. 1.27 in dimethyl- formamide). Treatment with anhydrous trifluoro- acetic acid resulted in L-asparaginyl-L-threonine (84%) amorphous softening at about 130" [a] -3" (c. 1.61 in water) (picrolonate + H,O m.p. 202" (decomp.) [a] + 7" (c. 2-24 in dimethyl-formamide)}. We thank N.V. Organon Oss which sponsored this research. (Received,May lst 1961.) E.g. Burwell Chem. Rev. 1954 54 615; Davies and Kenyon Quart. Rev. 1955 9 203. Roeske Chem. andInd. 1959 1121. Anderson and Callahan J. Amer. Chern. SOC.,1960 82 3359.Bromer Sinn and Behrens J. Amer. Chem. Soc. 1957 79 2810. Bodanszky and du Vigneaud J. Amer. Chem. Soc. 1959 81 5690. PROCEEDINGS The Structure of Thiolsulphonates; a Chemical Distinction Between Thiolsulphonate and Disulphoxide Formulations By R. R. CRENSHAW UNIVERSITY TENNESSEE, (VANDERBILT NASHVLLLE U.S.A.) and T. C. OWEN* (COLLEGE OF TECHNOLOGY, LIVERPOOL) THEthiolsulphonate structure R.SO,.SR’ is now toluene-p-thiol and toluene-p- [3fS]sulphon‘ ic an-generally acceptedly2 for the compounds RS,O,R’ in hydride. (Toluene-p- [35S]sulphonic acid required for which R and R’ are different. In cases where R and the preparation of the anhydride was obtained from R are identical however the nature of the SzOz (p-Me-C6H4.36S0,),0+ p-Me.C,H,-SH + grouping remains obscure the compounds having p-MeC6H4-35S02.SC,H,Me-pf p-MeC,H4-35S0,H been variously formulated as disulphoxides (I) thiol-sulphonates (11) and as mixed anhydrides (111).[aS]sulphuric acid by (IV) standard procedures.ll) 00 0 0 Reaction of the product (IV) with 2-acetamido-II I R-S-S-R R-S-S-R R-S-0-S-R ethanethiol gave the mixed disulphide (V)12 and toluene-p- ~5S]sulphinic acid (VI) characterised as A (1) (11) (111) p-MeC,H4.35S0,.S-C,H4Me-p + Ac.NHCH,.CH,-SH -+ Structure (HI) does not accord with observed (19 + p-MeC,H4-35S0,H proper tie^.^^^ Preparative procedures have given p-MeC,H4-S.SCH2-CH2-NHAc little guidance in a distinction between (I) and (II) (“1 (W syntheses giving identical prod~cts,~~~~~ and reactions p-tolyl 2,4-dinitrophenyl [35S]sulphone (VII).The Relative activity asc (RS,O,R = 100) Compound Found Required for Yield (%) R.SO.SO.R R.SO,.SR IV 100 - - - V 0-46b 50 0.00 70 VI (crude) VII 102 102b 50 50 100 100 I 90 Q Packard Tricarb liquid scintillation spectrometer; toluene solutions. b After repeated recrystallisation. c Corrected for minor self-quenching effects. favouring both (I)1p3~8and (11)1923599 and spectro-Table lists the radioactivities and yields of com-scopic evidencelo for (11) have been reported. We pounds (IV) (V) (VII) and crude (VI). now report the preparation of such a compound Complete recovery of the radioactivity of the having one of the sulphur atoms labelled with 35Sand ester (IV) in the sulphinic acid (VI) accords with the present evidence that in this case also the thiol- thiolsulphonate structure (11),while the disulphoxide sulphonate structure (11) is uniquely tenable.(I) or indeed any transfer of oxygen to the non- Radioactive p-tolyl toluene-p-thiolsulphonate(IV) radioactive sulphur atom of (IV)during its prepara- having only the oxygenated sulphur atom tion handling or subsequent reaction would transfer labelled was prepared by Field’s procedure’ from some of the activity to the disulphide (V). Conversely * During tenure of study leave. Hilditch J. 1910 1091. a Smiles and Gibson J. 1924 176; Miller and Smiles J. 1925 224; Gibson Miller and Smiles ibid. p. 1821. Fries Ber. 1914 47 1195. Knoevenagel and Polack Ber. 1908 41 3323. Leandri and Tundo Ann.Chim. (Italy) 1957 47 575. Trivedi J. Indian Chem. SOC.,1956 33 359. 7 Field J. Amer. Chem. SOC.,1952 74 394. Hinsberg Ber. 1908,41 2836,4294; 1909,42 1278; Frommes and Palma Ber. 1906,39 3308. Otto Annalen 1868 145 318; Ber. 1882 15 121. lo Cymeman and Willis J. 1951 1332. l1 Vogel “Practical Organic Chemistry,”Longmans Green and Co. London 1948 p. 532. l2 Field Owen Crenshaw and Bryan unpublished work. JULY 1961 since this thiolsulphonate (non-radioactive) was pre- pared by routes formally favouring structure (I)5p6 as well as (IQ2s5s7 and the same product was obtained oxygen transfer during the former preparation must have occurred. 251 We thank Dr. J. G. Coniglio and Dr. L. Field for their interest and are indebted to the U.S.Army Medical Research and Development Command for financial support. (Received April 20th 1961.) NitratonitrosylrutheniumComplexes By D. SCARGILL and J. M. FLETCHER ATOMIC RESEARCH HARWELL) ENERGY ESTABLISHMENT, (CHEMISTRY DIVISION FROM the properties1y2 of solutions of nitrato-com-plexes of nitrosylruthenium in aqueous and tributyl phosphate phases it has been postulated that these solutions contain not only [RuNO(NO,),(H~O)~] (I) which has already been isolated as its dihydrate but also the anions [RuNO(NO,),,H,O]-(TI) [RuNO(N0,),I2-(III),and the non-ionic compound [RuN0(N0,),(Bu3P0,) J (IV). Hitherto however attempts to prepare the complex (IV) which is detri- mental to the recovery of irradiated fuels or salts of the anions (JJ) and (111) have failed.We have now prepared the potassium salt of the anion (II) the complex (I) in its anhydrous form and complex (IV). The dark red potassium salt of anion (11) labelled with lo6Ru was made by evaporation nearly to dryness (12 hr.) in vacuo at 20" of stoicheiometric amounts of potassium nitrate and the nitrato-complexes of nitrosylruthenium in 8rvr-nitric acid followed by drying in vacuo at 50" [Found Ru 21.7; NO, 54.2; N 15.4; H20 (by Karl Fischer) 3.75; K 8-6; KNO, by X-ray diffraction and infrared spectroscopy <3. KRuNO(NO,)~,H,O requires Ru 23.1; NO, 56.8; N 16.1; H,O 4-1; K 8-9%]. Attempts to prepare K [RuNO(NO,),] by similar methods resulted in mixtures containing some potassium nitrate indicating that the reaction K [RuNO(NO,),H,O] +KNO,+K,[RuNO(NO3)5] + H,O does not readily go to completion.One sample (substance A) contained approximately equi- molar quantities of the potassium tetranitrato- and pentanitrato-salts potassium nitrate and water. The hydrated complex [RuNO(N0,),(H20),],2H20 pre-pared by a similar evaporation in the absence of potassium nitrate was rendered anhydrous by being held at 50" in vacuo for 12 hr. pound Ru 28.6; NO, 53.5; N 15.8; H20 10.5. RuNO(NO~),(H,O)~ requks Ru 28.7; NO, 52.8; N 15.9; H,O 10-2%]. Complex (IV) a dark red liquid dzl1.3 m.p. --6o" was made by stirring an excess of the an-hydrous complex (I) with purified dry tributyl phosphate for 1 hr. at 50". After centrifugation the complex was isolated by drying at 50" in vacuo for 5 hr.[Found Ru 11.35; NO, 20.7; N 6.3;Bu,PO, 62.7; H20 <05.RuNO(N03),,(Bu3P04) requires Ru 11.9; NOS 21.8; N 6.6; Bu~PO~, 62.7%]. The infrared spectra of these preparations all show N-0 stretching frequencies in the 1930-1950 m.-l region they also indicate both by the large separa- tion3 of the vl (1263-1267 cm.-l) and v4 (1508-1530 cm.-l) frequencies and by the low values for v2 (952-970 cm.-l) the strong bonding character of the nitrato-groups. Although by analogy with other nitrosylruthenium complexes the tetranitrato-complex (11) is likely to consist solely of the isomer with H20 trans to -NO preparations of the trinitrato-complexes (I) and (IV) may all contain the three possible stereoisomers.Heating the anhydrous complex (I) in vacuo below a cold finger did not give a volatile complex,4 e.g. [RuNO(NO,),] with two bidentate nitrato-groups there being decomposition to ruthenium dioxide at -150". However a comparison of the infrared spectra of the complexes now prepared with that of RUN,O,.~ suggests that the latter5 is the binuclear nitrosy lruthenium complex [(RuNO) ,O(NO,),] with bidentate nitrato-groups,6 these being formed by nitrosylruthenium under anhydrous conditions at -20". This view implies that (v4 -vl) is only increased marginally (-10 cm.-l) when a nitrato- group becomes bound to (RuNO)IrI by two ligands the increase for similar bonding to UO2*1 is also insignifican t.7 (Received May 2nd 1961.) Fletcher Brown Gardner Hardy Wain and Woodhead J.Inorg. Nuclear Chem. 1959 12 154. Martin and Gillies A.E.R.E. Hanvell Report C/R 973 1952. Ferraro J. Mol. Spectroscopy 1960 4 99. Addison and Gatehouse J. 1960 613. Martin Fletcher Brown and Gatehouse J. 1959 76. Fletcher J. Inorg. Nuclear Chem. 1958 8 277. Gatehouse and Comyns J. 1958 3965; Allpress and Hambly Austral. J. Chem. 1959 4 569. PROCEEDINGS ~ ~~ Mechanism of Merged Substitutionand Elimination By D. N. KEVILL and N. H. CROMWELL (AVERY OF CHEMISTRY UNIVERSITY LINCOLN U.S.A.) LABORATORY OF NEBRASKA NEBR. 2-BENZYL-2-BROMO-4,4-DIMETHYL- 1-TETRALONE in acetonitrile at 60.0"undergoes only a slow first-order decomposition (k 3-2 x sec.-l) and addition of bromide ions as tetraethylammonium bromide leads to a ready second-order decomposition (k 8-7 1.mole-l sec.-l). The reaction produces only the endocyclic unsaturated ketone 2-benzyl-l,4- dihydro-4,4-dimethyl-1-oxonaphthalene,' and pro-ceeds to at least 90% decomposition of the bromo- ketone. Piperidine hydrobromide in acetonitrile at 60.0" promotes a similar decomposition but the kinetic order in piperidine hydrobromide is found to be only one-half integral. The reaction rate for a given con-centration of piperidine hydrobromide is lower than for an identical concentration of tetraethylammon- ium bromide; e.g. for a salt concentration of 0.0200~, it is lower by a factor of about 7. Conductivity measurements show that in aceto- nitrile solution quaternary ammonium salts are more dissociated than only partially substituted am-monium salts.It appears that in order to promote elimination from the bromo-ketone the bromide ions must possess at least a certain minimum extent of dissociation and bromide ions tightly bound in an ion-pair are ineffective. Piperidine in acetonitrile at 60.0" also promotes elimination from the bromo-ketone and both a first- order and a second-order component to the kinetics are found k 7.1 x sec.-l and k 1.9 x 1. mole-I sec.-l. With an excess of piperidine the bromo-ketone was completely destroyed to form 87 % of endocyclic unsaturated ketone and 13 % of exocyclic unsaturated ketone no replacement product was found. The rate of self-decomposition of the bromo- ketone is considerably lower than the rate of first- order decomposition in the presence of piperidine and it is necessary to assume that the piperidine is essential for reaction to be able to proceed through the first-order component of the reaction path even though it does not enter into the rate-determining step; i.e.piperidine intervention prevents return to a less activated species of the intermediate formed in the rate-determining step of the first-order process. The presence of a first-order component of the kinetics in the reaction with piperidine indicates that the axial bromine-carbon bond1 of the bromo-ketone is fairly easily broken or at least stretched and it is probable that even in bimolecular reaction a con- siderable dipolar development occurs before reaction.Such a charge development would be consistent with the greatly enhanced reactivity of dissociated bromide ions over those in formally neutral ion-pairs. Attack by the nucleophile produces what is essentially an ion-pair (I) with however the prob- able existence of weakly developed covalent binding and with also the possible retention of weak binding to the outgoing bromide ion. Whether the kinetics observed are of first or second order depends upon the relative rates of these first and second stages of the mechanism. Attack by uncharged nucleophiles at a positively charged centre will be less favoured as regards orientation for attack than will be attack by charged nucleophiles; and it appears that for piperidine- promoted elimination the charge developed before attack is in some instances sufficient for the first stage of the mechanism to be rate-determining thus giving rise to a first-order component to the kinetics.The weakly bound condition (I)can be considered as a transient intermediate either it collapses to give the replacement products or the nucleophile abstracts a /%proton. Elimination will be especially favoured if steric factors inhibit collapse. As proposed the elimination mechanism has characteristics of a borderline S 1-S,2 mechanism but the nucleophilic attack is finally diverted from the carbon atom centre to the axial /%hydrogen atom. The mechanism proposed for the elimination promoted by attack by bromide ion on 2-benzyl- 2-bromo-4,4-dimethyl-l-tetralone in acetonitrile differs from that proposed by Winstein et aL3 for elimination through attack by bromide ion on trans-4-t-butylcyclohexyl toluene-p-sulphonate in acetone in two important aspects.It is suggested that our transient intermediate is highly asymmetric and more in the nature of an ion-pair involving the attacking nucleophile than of an intermediate with characteristics of an S,2 type transition state; also that the axial /3-proton is abstracted by the attacking nucleophile and not by the displaced nucleophile. Hassner and Cromwell J. Amer. Chem. Soc. 1958 80 893; Hassner and Cromwell ibid, p. 901 ;Cromwell Ayer! and Foster ibid. 1960 82 130. Walden and Birr 2.phys. Chem. 1929 A 144 269.Winstein Danvish and Holness J. Amer. Chem. SOC.,1956 78 2915. JULY 1961 When the attacking agent is a base Y such as piperidine some co-ordination of Y with the carbonyl-carbon atom in the transition state is also to be expected. ,Y--*H + ?HB This scheme is a more detailed description of the mechanism first suggested for such reactions in a publication by one of us submitted in June 1956.4 The authors thank the National Science Founda- tion U.S.A. for a grant to support this work. (Received ApriZ loth 1961.) Hassner Cromwell and Davis J. Amer. Chem. SOC.,1957 79 230. intermolecular Interactions in Mixed Crystals By D. P. CRAIGand T. THIRUNAMACHANDRAN (WILLIAM RAMSAY AND RALPH FORSTER LABORATORIES UNIVEHSITY LONDON) COLLEGE CHOUDHURY measured the absorp- and GANGULY~ tion of polarised light by tetracene molecules em- bedded in anthracene crystals; they found that the ratio of intensities for light polarised along the b and a monoclinic axes (bla = 1.9 1) is much lower than for perfectly free molecules oriented in the anthracene lattice (7.7 1) and approaches the value for pure anthracene itself which they give as 1.8 :1.The reduc- tion in the ratio is caused by a three-fold intensifica- tion of the a absorption intensity over the oriented- gas value and a weakening of the b intensity by a factor 0.82. These results must reflect rather strong intermolecular interactions which cannot be of the excitation resonance type leading to Davydov splitting in pure crystals since the energy levels of impurity and “host” are not equal.A theoretical study shows that the interactions are of a type occurring also in pure crystals in which however they are only of second-order magnitude compared with resonance effects.2 Departures from the oriented-gas ratio of intensities of absorption along two axes in pure crystals are caused by crystal- induced mixing of different molecular excited-state wave functions under the influence of electrostatic interactions between molecules. These deviations are easily calculated from the solution-spectra and crystal-structure data. In a mixed crystal similar mixing can be expected to occur between a chosen state of the guest with certain excited states of the surrounding host molecules.Measurement of in- tensity or of the polarisation ratio then gives a result which could not have been anticipated from know-ledge of the free-molecule spectrum and of the molecular orientation since it depends also on the characteristics of the host. In the tetracene-anthracene system the 4800 A transition of tetracene is mixed both with the intense 2500 A transition of anthracene and with the weaker 3800 A system. By making the assumption that the tetracene guest molecule adopts the same orientation in the lattice as the anthracene it has replaced and ming only the frequencies and intensities from the free-molecule spectra of guest and host we calculate a polarisation ratio of 2.8 1 with accompanying changes as shown in the Table.Light absorption by tetracene in anthracene (4800 A) Calc. Expt. Intensification factor for a absorption for b absorption Polarisation ratio b/a Polarisation ratio without inter- 3 1-07 2.8 3.3 0.8 1.9 action 7.7 - The agreement with experiment may be a little better than this indicates because Choudhury and Ganguly’s methods seem to lead to polarisation ratios that are somewhat low. Thus both Wolf3 and Bree and Lyons4 give values near 3:l for pure anthracene instead of 1.8 1. Tn any case it seems clear that interactions of this type are quite strong enough to lead to the observed marked changes in mixed crystal spectra. (Received April 28th 1961.) Choudhury and Ganguly Proc. Roy. SOC., 1960 A 259,419.Craig J. 1955 2302. Wolf Solid State Physics 1959 9 1. Bree and Lyons J. 1956,2662. PROCEEDINGS The Biosynthesis of Amuryllidaceae Alkaloids By D. H. R. BARTON and G. M. THOMAS G. W. KIRBY,J. B. TAYLOR (IMPERIAL LONDON S.W.7) COLLEGE IT has been proposedl that galanthamine (11) and other Amaryllidaceae alkaloids are formed biosyn- thetically by oxidative coupling of phenols of the type (I). Preliminary experiments2 showed that both [2-14C]tyrosine and the phenol (Ia) were incor-porated into galanthamine in King Alfred daffodils. The incorporation of the labelled tyrosine (without scrambling) into lycorine has been demonstrated by Battersby Binks and Wildn~an.~ Our further experi- ments briefly reported here have shown incorpora- tion of various phenols of type (I) into Amaryllidaceae alkaloids.The hypothetical precursors (Ia and b) labelled with 14C in their N-methyl groups were prepared by the method described earlier.2 The trihydroxy-derivative (Ib) was isolated as its crystalline hydro- chloride m.p. 207-208 ".Both compounds were fed separately to King Alfred daffodils and after one week the major alkaloids were isolated and purified. To show that no transmethylation had taken place in the plant the methoxyl and N-methyl groups of the isolated galanthamine were cleaved in turn with hydrogen iodide by the usual microanalytical pro- cedure. The liberated methyl iodide was collected in ethanolic triethylamine and counted as triethyl-methylammonium iodide.The results are tabulated. It is seen that both precursors are incorporated intact into galanthamine with an efficiency similar to that observed for [2-14C]tyr~~ine.2 0-benzyl[ 1J4C]tyramine which was isolated as its hydrochloride m.p. 202-204" (decomp.). The tyramine was allowed to condense with 3,4-dibenzyl- oxybenzaldehyde in methanol and the intermediate OR I OMe imine was reduced directly with sodium borohydride. After purification through its hydrochloride m.p. 148-149" the amine (I; R1 = R2 = R3= PhCH, R4 = H) was hydrogenated on palladium-carbon giving labelled norbelladine hydrochloride m.p. 174-1 75'. This material was incorporated into galanthamine in snowdrops (Galanthus elwesii) in 0.053% yield. In King Alfred daffodils incorporation Precursors (m Alkaloid Fraction Fraction Yield* Incorpn.of 14Cin Yield* In-of 14C in Yield* Incorpn. corpn. (%I (%I Me0 MeN (%I (%I Me0 MeN (%I (%) Galanthamine (lI) 0.024 0.014 0-02 0.95 0.025 0.018 0.03 0.95 0.027 0.014 Galanthine (111) 0.015 0.OOO -0.019 0401 -0.026 0.003 Hzmanthamine (IV) 0.026 O.Oo0 -0.029 0.OOO -0.029 0.25 * Yield of alkaloid calculated on weight of fresh plant material. The fully demethylated phenol (Ic) norbelladine should serve as a precursor for many Amaryllidaceae alkaloids. We have spnthesised norbelladine labelled in its carbon skeleton in the following way. 4-Benzyl- oxybenzyl chloride was treated with sodium [l'Cc]- cyanide in dimethyl sulphoxide and the resulting nitrile reduced with lithium aluminium hydride to into galanthamine galanthine (111) and hznian- thamine (IV) was observed norbelladine being a particularly efficient precursor for haemanthamine (see Table).The dihydroxy-compound (Id) was also obtained as its hydrochloride m.p. 195-197" by the pro- cedure described for norbelladine but by using Barton and Cohen Festschrift Arthur Stoll Birkhauser Verlag. Bask 1957 p. 117. Barton and Kirby Proc. Chem. Soc. 1960 392. Battersby Binks and Wildman Proc. Chem. Soc. 1960 410. JULY 1961 255 0-benzylisovanillin as starting material. A study of We consider these results as well as those reported the incorporation of this compound into King by Battersby Wildman and their collaborator^,^^^ to Alfred daffodil alkaloids and the degradation of be good evidence in support of our biogenetic labelled galanthamine and hzmanthamine are in hyp0thesis.l progress.(Received May 18th 1961 .) * Battersby Binks Breuer Fales and Wildman Proc. Chem. SOC.,1961 243. We express our cordial appreciation to Dr. A. R. Battersby for a copy of his communication sent us at time of submission to these Proceedings. Derivatives of 3-Amino-3,6dideoxy-~-glucoseand -~-talose By A. C. RICHARDSON (THE UNIVERSTI"~, BRISTOL) of methyl 3-acetamido-2,4,6-tri-O-acetyl-3-deoxy-a-described. tidopyranoside6 (-17,300" calculated from the (Rsceived May 3 Is? 1961 .) Baer and Fischer J. Amer. Chem. SOC.,1959 81 5184; 1960 82 3709; Baer Chem. Ber. 1960,93,2865. a Richardson and Fischer Proc.Chern. SOC.,1960 341; J. Amer. Chern. SOC., 1961 83 1132. Foster and Horton Adv. Carbohydrate Chem. 1959 14 231; Wiley Research Today (Eli Lilly and Company) 1960 16 3; Huber Schier and Druey Helv. Chim. Acta 1959 42 2447. Haskins Hann and Hudson J. Amer. Chem. SOC., 1946,68 628. Baker and Schaub J. Org. Chern. 1954 19 646; R. W. Jeanloz Tarasiejka and D. A. Jeanloz J. Org. Chem. 1961,26 532. R. W. Jeanloz and D. A. Jeanloz J. Org. Chem. 1961 26 537. Hudson J. Amer. Chem. SOC. 1909,31 66. * Lemieux Kullnig Bernstein and Schneider J. Amer. Chem. SOC. 1958 80 6098. Walters Dutcher and Wintersteiner J. Amer. Chem. Soc. 1957 79 5076. CYCLISATIONvarious dialdehydes with nitro- of methane and reduction of the resulting nitro- derivatives have led to a variety of 3-amino-3-deoxy-aldoses.ly2 As 3-amino-3,6-dideoxyhexose deriva-tive~~ have been isolated from antibiotics the nitromethane cyclisation has now been applied to the dialdehyde produced by periodate oxidation of methyl a-L-rhamnopyrano~ide.~ The resulting mixture of 3-nitro-derivatives failed to crystallise but on hydrogenation with Raney nickel gave a 25-31 % yield (based on the rham- noside) of methyl 3-amino-3,6-dideoxy- a-~-gluco- pyranoside (I) m.p.177-178" [a] -145" (in H,O). The stereochemistry of this product was indicated by comparison of its molecular rotation with similar derivatives of the gluco-configuration and by subsequent experiments. The amino-glycoside (I)was converted into a triacetyl derivative de-0-acetylation of which afforded the acetamido-derivative (11).This was con- verted into a di-0-methanesulphonate (111) by the action of methanesulphonyl chloride in pyridine. The inversion of sulphonyloxy-groups situated trans to an acylamino-group with sodium acetate in 95% 2-methoxyethanol has already found use for syn- thesis5s6 and structural elucidation2 By this reaction our sulphonate (111) gave a 60% yield of a sulphur- free compound isomeric with (11) indicating that both methanesulphonyloxy-groupshad been trans to the 3-acetamido-substituent which is compatible only with the gluco- or ido-configuration. However [MI of our triacetate (-33,800") differs from that D-form) and [MI of our monoacetyl derivative (11) (-31,OOOo) differs from that of methyl 3-acetamido- 3-deoxy-a-~-idopyranoside~ (-17,000").Conse-quently the gluco-configuration for (I) is indicated and the product of the inversion is methyl 3-acetam- ido-3,6-dideoxy-a-~-talopyranoside (IV). Acid hyd- rolysis of the taloside afforded crystalline 3-amino- 3,6-dideoxy-~-talose hydrochloride. H H H Acid hydrolysis of the amino-glucoside (I) afforded a syrupy reducing sugar which with acetic anhydride-pyridine afforded two isomeric tetra-acetates (V) which were readily separated by frac- tional crystallisation. The anomeric configurations of each were assigned by application of Hudson's convention' and of nuclear magnetic resonance spectroscopy the results of which were in accord with those of Lemieux et aL8 on sugar polyacetates and will be reported later.The naturally occurring 3-amino-3,6-dideoxy-~- hexose myco~arnine,~ does not have the same configuration as the ghco-or talo-isomer here 256 PROCEEDINGS The Electronic Spectra of Alkyl and Double-bond Carbonium Ions By P. G. FARRELL and S. F. MASON (CHEMISTRY THEUNIVERSITY, DEPARTMENT EXETER) SECONDARY or tertiary alkyl carbonium ions1.2 and the unconjugated diene carbonium ion3 (I) in con- centrated sulphuric acid solution give absorption bands about 2900 and at 3500 respectively whilst both bands are observed4 in the spectrum of the ion (11) (Table). To obtain more information about the transitions involved in these absorptions the spectrum of bicyclo [2,2,1] heptadiene in concentrated sulphuric acid solution has been measured.In the ion formed presumably (111) the distance between the vinyl group and the positively charged carbon atom is shorter than in the ion (11),and whilst both of these ions give similar spectra the longer-wave- length band has a higher frequency and a larger intensity in the case of the ion (111) (Table). Ultraviolet absorption spectra of carbonium ions in sulphuric acid solution. Values in italics refer to shoulders. Ion Amax. (A) 6 Ref. Me&+ 2920 6300 3 (1) 3500 5000 4 (I1) t8Z 5 5600 ("I) 3350 1000 The energy interval (0.7 ev) between the alkyl carbonium ion absorption and that of the ion (I) is of the same order as but less than the difference (0.9-1.1 ev) between the ionisation potential5 of an olefin and the corresponding paraffin suggesting that these absorptions arise from a transition involving the transfer of an electron to the positively charged carbon atom from the alkyl groups or from the un- saturated group respectively.The calculated charge distributions in the highest occupied and the lowest unoccupied electronic energy levels of the isopropyl and the t-butyl cations6 indicate2 that the 2900 A absorption of these ions has a charge-transfer character. For charge-transfer transitions of the type here considered the frequency of absorption v is given by:' v = I -E + 2p/(I -E) (1) where I is the ionisation potential of the donor the alkyl or unsaturated group E is the electron affinity of the acceptor the positively charged carbon atom and p is the resonance energy of interaction between the classical (e.g.,UIa) and the charge transfer (e.g..IIIb) configurations. Thus with a given acceptor the frequency of absorption should decrease though in less than direct proportion according to eqn. (l) as the ionisation potential of the donor is reduced in accord with the observed spectra of the alkyl car- bonium ions and that of ion (I) (Table). Further for the double-bond-carbonium ion charge-transfer absorption the resonance energy p should become larger as the distance between the double bond and the positively charged carbon atom is reduced owing to the better overlap between the n-orbital of the former and the vacant 2porbital of the latter.A larger resonance energy Is should result in an in- crease of the absorption frequency and of the band- maximum extinction coefficient expectations which are observed on comparing the spectra of the ions (11) and (111) (Table). HH HH (ma> AH H&H H H (mb) HH H The spectrum of the ion (I) might be expected to show the absorption band of an alkyl carbonium ion as well as of a double-bond carbonium ion. How- ever the intensity of the alkyl carbonium ion absorp- tions2 tend to fall off as the number of C-H bonds available for hyperconjugation or .zr-charge transfer a to the positively charged carbon atom is reduced. The ion (I) has no such cy C-H bonds available the C-H bonds in the 1-and the 4-position lying in the nodal plane of the vacant 2p-orbital of the 7-carbon atom.(Received April 28th 1961.) Vidal Kohn and Matsen J. Chem. Phys. 1956 25 180; Lavrushin and Verkhovod J. Gen. Chem. U.S.S.R., 1956 26,3005. Rosenbaum and Symons Mol. Phys. 1960,3 205. Winstein and Orronveau J. Amer. Chem. SOC.,1960 82 2084. Leal and Pettit J. Amer. Chem. SOC.,1959 81 3160. Watanabe J. Chem. Phys. 1957 26,542. Muller and Mulliken J. Amer. Chem. SOC., 1958 80 3489. Hastings Franklin Schiller and Matsen J. Amer. Chem. SOC., 1953 75 2900. JULY 1961 257 Cephalosporin P By B. M. Bm T. G. HALSALL, E. R. H. JONES and G. LOWE PERRINS OXFORD (THE DYSON LABORATORY UNIVERSITY) CEPHALOSPORIN an antibiotic produced by a P, strain of Cephalosporium was shown by Burton Abraham and Cardwelll to be a tetracyclic pos- sibly steroidal monocarboxylic acid C32H4808.The oxygen atoms were accounted for by a carboxylic acid grouping (tetrasubstituted ap-unsaturated) and by two hydroxyl and two acetoxyl groups. One of the latter was easily hydrolysed leading to a mono- deacetyl derivative. On hydrolysis of the second a dideacetyl-lactone was formed. An isolated double bond was also present. Through the generous help of Mr. B. K. Kelly of the Medical Research Council’s Antibiotics Research Station Clevedon more cephalosporin P has become available and it has been possible to in- vestigate it further. The results obtained the more significant being described below are consistent with the structure (I; R = Ac R’ = H).Cephalosporin P belongs indeed to the polyiso- prenoid group of compounds [2-C14]mevalonic lactone being incorporated into it by the micro- organism. 0 II Ozonolysis of its methyl ester gave acetone. This arose from -CH =CMe since dihydro-cephalosporin P methyl ester which contained still the a/% unsaturated ester grouping did not show the signal indicative of an olefinic proton originally present in the nuclear magnetic resonance spectrum (T = 4.87) of the methyl ester. Ozonolysis of the methyl dihydro-ester gave a compound (II)which on treat-ment with acid but not alkali afforded a cisoid a/?-unsaturated ketone (HI) (Amax. 2450 A;E 9,600). To account for this result an acetoxy-group is required at C(13).Further a blocking group pre- sumably methyl is needed at otherwise a transoid 13-en-17-one should be formed.2 Oxidation of cephalosporin P methyl ester (I ; R = Ac R’ = Me) with chromic acid gave a di- ketone containing no additional chromophore but the monodeacetyl compound (I; R = H R’ = Me) gave a yellow triketone containing a non-enolic a-diketone group. The a-glycol group which must be present in monodeacetylcephalosporinP methyl ester forms an isopropylidene derivative and under- goes rapid fission with lead tetra-acetate (k2, 430 1.mole-l min.-l in acetic acid) typical of a cis-glycol. Oxidation of the monodeacetyl-isopropylidene derivative with chromium trioxide in pyridine gave a monoketone with optical rotatory dispersion like that of a 3-keto-5a-steroid.The dispersion of the di-ketone from cephalosporin P methyl ester was more akin to that of a 3,6-dioxo-5a- than of a 3,7-dioxo- 5a-steroid. The resistance of the diketone to deacetoxylation with zinc-acetic acid and the ease of hydrolysis of one of its acetate groups together with a peak at T = 4.35 in the nuclear magnetic resonance spectrum of the parent methyl ester suggested that this group was equatorial. Further the difficulty of acetylation of the parent compound indicated that the 6-hydroxyl group was axial while the rate of cleavage of the a-glycol was closer to that of a 6P,7P-diol (kZ5160 lmole-l min.-l in acetic acid) than of a 6a,7a-diol (kZB 42 1.mole-l mineA1 in acetic acid).3 An equatorial 4a-methyl group was indicated since the amplitude of the optical rotatory dispersion curve of the 3-monoketo-derivative in methanol was not suppressed by acid and by the lack of enolisa-tion of the a-diketo-group which would give rise to a strong non-bonded interaction between the equatorial methyl group and the enolic 6-hydroxyl group.Burton Abraham and Cardwell Biochem. J. 1956 62 171. Ansell and Brown J. 1958,2955. Angyal and Young J. Amer. Chem. SOC.,1959 81 5251. Djerassi “Optical Rotatory Dispersion,” McGraw-Hill New York 1960 p. 148. Wenkert and Jackson J. Amer. Chem. SOC.,1958 80,211. The optical rotatory dispersion of the ap-un-saturated ketone (ILI) and its dihydro-derivative suggests that the 14-methyl group has the @on- figuration.No firm conclusion can however yet be drawn about the configuration of the 13-acetoxy- group from the dispersion of the ketone (II). The 3-hydroxyl group must be axial and hence have the a-configuration since oxidation of the monode- acetyl-isopropylidene derivative followed by reduc- tion with sodium borohydride gave the epimeric alcohol. The original a-configuration results on catalytic hydrogenation of the 3-0x0 group with platinum in acetic acid containing hydrochloric acid.6 The dideacetyl-lactone (IV) gave a tetrahydro-* Barton J. 1953 1027. Greenhalgh Henbest and Jones J. 1952 2375. PROCEEDINGS derivative which was converted into an isopropyli- dene derivative; this had vmax 1776 cm.? (in CClk indicative of a y-lactone.Oxidation of the tetrahydro- derivative gave a yellow triketone acetylation of which afforded a dienol diacetate (V) 2875 A E 15,400).' The authors thank Professor W. Klyne for the determination of the optical rotatory dispersion curves and Dr. L. M. Jackman for the nuclear magnetic resonance data. One of them (B.M.B.) thanks the Department of Scientific and Industrial Research for a maintenance grant. (Received April 20th 1961 .) A Rearrangement of Some Alkoxyphosphazenes By B. W. FITZSIMMONS and R. A. SHAW OF CHEMISTRY BIRKBECK (DEPARTMENT COLLEGE UNIVERSITY OF LONDON MALETSTREET w.c.1) RECENTLY we reported the preparation of some allcoxyphosphazenes of types (I) and (III).l Re- arrangement of some of these compounds by the transformations (I)-+ 01) and (III) -+ (IV)is now described.y/"OR (1) R The liquid ester1 (I; R = Et) b.p. 115-116"/0~1 mm. when heated at 200" for 1 hour gave the crystal- line N-ethyl isomer (II; R = Et) m.p. 74-75' identical with an authentic sample prepared by the method of Ratz and Hess.2 Similarly the correspond- ing eight-membered ring compound1 (III; R = Et) m.p. 45-47' gave the isomer (IV; R = Et) m.p. 208-210" (Found C 35.1; H 7.6; N 10.6. C16H40N408P4 requires C 35.6; H 7.4; N 10.4%) after 4 hours' heating at 200". Fitzsimmons and Shaw Chem. and Ind. 1961 109. Ratz and Hess Chem. Ber. 1951 84 889. Daasch J. Amer. Chem. Soc. 1954 76 3403. Acid degradation of the normal compounds (I and 111;R = Et) gave ammonia but similar treatment of their isomers (I1 and IV; R = Et) gave ethylamine.Infrared spectroscopy supports these degradative experiments. The rearrangement brings about the disappearance of the characteristic (P=N) bandsS which are present in the spectra of compounds (I and 111; R = Et) at 1225 and 1320 cm.-l respectively. Bands at 1250 cm.-l (P=O)* appear in the spectra of the rearrangement products (I1 and IV; R = Et). It is likely that this rearrangement takes place by a mechanism where a ring-nitrogen atom attacks an a-carbon atom of an alkoxyl group. It is analogous to the thermal decomposition of diethy1 N-phenyl- phosphoramidate which has been shown to give a mixture of ethyl- and diethyl-anilit~e.~ It is also similar to a rearrangement of 2,4,6-trimethoxy-l,3,5- triazine.* We have previously1 drawn attention to the stability of the phenyl esters (I and 111; R = Ph) where there is no point of attack for a nitrogen atom and these may be recovered unchanged after 26 hours' heating at 300'.We are grateful for the financial support of the Agricultural Research Service of the United States Department of Agriculture and to D.S.I.R. for a grant. (Received May 26th 1961 .) Bellamy "The Infrared Spectra of Complex Molecules," 2nd edn. Methuen London 1958 p. 312. Cadogan J.,1957 1079. Hofmann Ber. 1870 3 264. JULY 1961 259 A Kinetic Study of the Addition of the Ethyl Radical to Vinyl Monomers By D. G. L. JAMES*and D. MACCALLUM OF CHEMISTRY COLLEGE OF ST.ANDREWS) (DEPARTMENT QUEEN'S OF THE UNIWRSITY IN an attempt to place the reactivity of vinyl mono- mers on a quantitative basis we are measuring the energy of activation for the addition of the ethyl radical to a representative series of monomers in the gas phase. Vinyl acetate and styrene display con- trasted reactivity in polymerisation and have been chosen to introduce this study. Styrene shows much the greater reactivity towards initiation by free radicals and unlike vinyl acetate also responds readily to initiation by certain cations and ani0ns.l Ethyl radicals are generated by the photolysis of diethyl ketone. The method is essentially a com- parison of the rates of two competing reactions at a series of temperatures At higher light intensities and below 160" C.it may be shown that where the symbol R represents the rate of formation of the product Y in mol. sec.? ~m.1~ of illuminated volume and [B] represents the concentration of the appropriate monomer. A discussion of the reaction scheme and the validity of the rate equation the experimental technique and results for certain alkenes have been given previously.2 The rate con- stant k can be calculated from the known value3 of k, but for comparison the ratio k,/k,* is adequate. The results for vinyl acetate and styrene are com- pared with those obtained previously for hept-l-ene in the Figure and the Table. These results show that the greater reactivity of styrene is due to a lower energy of activation for the addition.There is no significant difference between the values of the pre- exponential factor; this is not surprising as the steric conditions must be very similar for these terminal vinyl groups. A low energy of activation for the addition of the ethyl radical is likely to be observed (a) if the product radical has a higher degree of resonance stabilisation than the reactant monomer molecule and (b)if ionic forms contribute significant- ly to the stability of the activated complex. The first of these factors is probably the main cause of the greater reactivity of styrene. Addition of the ethyl radical to vinyl monomers El -&EZ 13 + log(AJA24) (kcal./mole) Styrene 4.0 f0.6 4.9 0-3 Vinyl acetate 6-8 f0.4 5.3 k0.3 Hept-l-ene 7-0-C 0.2 5-2 f0.1 \ \ I I I I I1 11\1 2-4 ' 2-8 3-2 i03/Temp.("K) Addition of the ethyl radical to vinyl rnononrers.A Styrene. B Vinyl acetate. C Hept-1-ene. A parallel may be found in two conclusions which are implicit in the propagation constants measured for styrene and vinyl acetate respectively in homo- geneous copo1yrnerisation.l First the vinyl acetate molecule is only about one-fiftieth As reactive as the styrene molecule towards the addition of any given polymer radical ; secondly the vinyl acetate radical is about one-thousand times as reactive as the styrene radical towards any given monomer molecule. The higher reactivity of the styrene mole- cule towards the addition of free radicals is due at least in part to the activating effect of the phenyl radical in conjugation with the vinyl double bond; the adduct radical enjoys a far greater degree of stabilisation than the moncmer molecule and the energy of activation for addition is correspondingly low.The vinyl acetate molecule is comparatively un-reactive because the acetoxy-group contributes little to the stabilisation of either monomer or radical. The polar factor may be discussed in terms of * Present address Department of Chemistry University of British Columbia Vancouver 8 B.C. Mayo J. Chem. Editc. 1959 36 157. James and Steacie Proc. Roy. SOC.,1958 A 244,289 297. Shepp and Kutschke J. Chem. Phys. 1957 26 1020. donation of an electron to the monomer molecule by the ethyl radical which has an ionisation potential4 of 8.78 v.Styrene possesses the greater electron affinity; unlike vinyl acetate it may be polymerised by treatment with a solution of sodium in liquid ammonia and it is reduced at the dropping mercury electrode with a half-wave potential5 of -2.39 v. However studies of the comparative efficiency of the solvents carbon tetrabromide and triethylamine as chain-transfer agents6 reveal that the radicals derived from vinyl acetate and from styrene are character- PROCEEDINGS istically weak electron donors; consequently the polar effect is likely to be of only minor importance in the addition of the ethyl radical to these monomers. Acrylonitrile shows a high reactivity towards the ethyl radical suggesting a considerable polar effect1 for this addition whereas results obtained with cyclohexa-l,3-diene indicate that steric effects will be significant for the non-terminal double bond.2 A report on the reactivity of these and other monomers is in preparation.(Received May 23rd 196 1.) Farmer and Lossing Cattad. J. Chem. 1955 33 861. Brezina and Zuman “Polarography in Medicine Biochemistry and Pharmacy,” Interscience Publ. Inc. New Yor k, 1958 p. 749. Bamford and White Trans. Faraday SOC.,1956 52 717. Nucleophilic Additions of 8-Substituted Pteridines and their Biochemical Significance By THOMAS ROWANand H. C. S. WOOD (THE ROYAL COLLEGE AND TECHNOLOGY, OF SCIENCE GLASGOW) and PETER HEMMERICH (INSTITUT CHEMIE BASEL) FUR ANORGANISCHE AN DER UNIVERSITAT THE tetrahydrodioxopteridine (I; R = D-ribityl) (Masuda’sl “G-compound”) and the hexahydrotri- oxopteridine (11; R = D-ribityl) (Masuda’sl “V-compound”) have been isolated together with ribo- flavin from cultures of Erernotheciurn ashbyiil and Ashby a gossyp ii.Biochemical experiments with cell- free extracts of these organisms show that the pteridine (I; R = D-ribityl) can function as an efficient precursor of the 7-0x0-compound (11; R = ~-ribityl).~g~ This transformation can be interpreted by chemical analogy in terms of the following results (In> a We have shown by spectrophotometric methods that “quinonoid” pteridines such as (I) readily undergo nucleophilic attack at position 7. Thus the pteridine (I; R = CH2CH,*OH),5Am,,.258 277 sodium hydroxide gave an anomalous strong hypsc- chromic shift to Amax. 231 283 and 316 mp at pH 13 consistent with the data of Pfleiderer and Nubel.6 We found the latter absorption to be virtually identical with that of the 7,s-dihydropteridine (111; R = CH2*CH2-OH,R’ = H),’ Amax. 231 283 and 317 mp. We therefore conclude that the disap- pearance of the visible band in the spectrum of quinonoid pteridines (e.g. I) at higher pH values indicates that the anion of the “hydrated” form (111; R’ = OH) is formed. In the same way and at lower pH values the yellow “quinonoid” pteridines such as (I) add hydrogen cyanide sodium hydrogen sulphite etc. with complete decolorisation giving compounds (111; R’ = CN SO,- etc.).The hydra- tion in particular is promoted by metal ions giving colourless chelates such as (IV). We suggest that compound (111; R = D-ribity] R’ = OH) which is a carbinolamine is an inter- mediate in the biological conversion of (I) into (11) which makes the pyrazine ring-closure in quinonoid pteridines such as (I) easily reversible. We have brought about this transformation in vitvo by re-fluxing the carbinolamine (111; R = D-ribityl R’ = OH) with pyruvate to give the 7-oxopteridine (11; R = D-ribityl) (identified by paper chromatography and 405 mp at pH 5.8 on dissolution in 0.1~- and spectral comparison with an authentic specimen). Masuda Pharm. Bull. (Japan) 1956 5 375; Masuda Kishi and Asai ibid 1957 5 598; Forrest and McNutt J.Amer. Chem. Sac. 1958 80 739. Maley and Plaut J. Biol. Cheni. 1959 234 641 3010. Kuwada Masuda Kishi and Asai Pharm. Bull. (Japan) 1058. 6. 618 Korte and Aldag Annalen 1959 628 144. Cresswell and Wood J. 1960 4768. Pfleiderer and Niibel Chem. Ber. 1960 93 1406 Rowan and Wood unpublished work JULY 1961 26 1 On the other hand we have been unable to repeat 7-methyl group.8 A definite decision between the the autoxidation of the compound (I; R = D-ribityl) above alternatives can only be made however as a to a compound very similar to (11; R = D-ribityl) result of experiments in vivo. which has recently been reported.8 We therefore believe that in the biological transformation of the The authors thank Dr. W. Pfleiderer (Stuttgart) dioxopteridine (I) into the trioxopteridine (II) dis-for a generous gift of the 8-methylpteridine (I; R = placement of the biacetyl residue by a pyruvate resi- Me) Professor A.J. Birch for helpful discussion and due is more likely than oxidative removal of the the D.S.I.R. for a Research Studentship (to T.R.). (Received April 25th 1961.) Korte Aldag Ludwig Paulus and Storiko Annden 1958 619 70. The Structures of Phytoene Phytofluene [-Carotene and Neurosporene By J. B. DAVIS L. M. JACKMAN and B. C. L. WEEDON P. T. SIDDONS (IMPERIAL OF SCIENCE LONDON, COLLEGE AND TECHNOLOGY S.W.7 and QUEEN MARY COLLEGE LONDON,E.l) IT has been suggested that phytoene phytofluene The nuclear magnetic resonance spectra of the (-carotene and neurosporene are intermediates in polyenes show no bands due to methyl groups 011 the biosynthesis of lycopene (VI) and other caro- saturated carbon atoms and thus eliminate all ten0ids.l On the basis of analytical and degradative structures1g3 embodying this feature.The methyl studies Rabourn and Quackenbush2 have proposed bands observed and their relative intensities (see that these compounds be formulated as (I) (II) Table*) uniquely confirm structures (I) (11) and (HI) and (V) respectively. We have now confirmed (V) in particular the location of the conjugated these structures. systems. The relative intensities of the cis-and trans-* The band assignments have been discussed previously; “in-chain” methyl groups (-CH :CHCMe :CHCH:CH-) can be resolved from “isoprenoid” methyl groups (-CH :CHCMe:CH-CH,-) ; it is also possible to distinguish between methyl groups which are cis and those which are trans to the alkyl substituent at Cp) in unconjugated tri- substituted double bonds (-CH,C(a)Me:C(p)H-CH,-).4s5 Cf.Goodwin J. Sci. Food Agric. 1953,5 209; Adv. Enzyymology 1959,21,295; Grob in “Biosynthesis of Terpenes and Sterols,” Churchill London 1959; Mackinney “Metabolic Pathways,” ed. Greenberg Academic Press New York 1960 p. 481. Rabourn and Quackenbush Arch. Biochcm. Biophys. 1956 61 111; unpublished work; abs. Papzrs Amer. Chem. SOC. Sept. 1957 p. 88C; cf. Zechmeister Prog. Chem. Org. Nut. Prod. 1958 15 39. Eugster Linner Trivedi and Karrer Helv. Chim. Acta 1956 39 690. Barber Davis Jackman and Weedon J. 1960 2870. Bates and Gale J.Amer. Chem. Soc. 1960 82 5749. olefinic methyl bands show that all non-terminal un- conjugated double bonds in the four polyenes like those in natural ~qualene,~~~ possess the trans-configuration (i.e. have a cis-olefinic methyl). A mixture of phytoene isomers (Amax. 298 286 276 mp; Vmax. 957 and 766 cm.-l),t differing in their stereochemistry about the central triene unit was synthesised (Scheme A) from “all-trans”-geranyf- linalool (VII).’ Its nuclear magnetic resonance spectrum in the range 6.5-9.5 p.p.m. was identical with that of natural phytoene (vmax. 766 cm.?) which is believed to possess a cis-configuration about the central double bond. A partial separation of the trans- from the cis-isomers in the synthetic mixture was achieved by formation of a thiourea complex.“all-trans”-Phytofluene (Amax. 366 347 331 mp; Vmax. 1631 962 cm.?) was synthesised (Scheme B) from nerolidol (IX) and was identical with a sample Scheme 6 Scheme C Scheme D PROCEEDINGS from carrot oil (spectra; mixed chromatogram). The nuclear magnetic resonance and degradative evidence for [-carotene was compatible with both the symmetrical (311) and unsymmetrical (IV) struc-tures. The “all-trans”-isomer (m.p. 38-42”; Amax. 425 401 380 mp; vmax. 963 cm.-l in cyclohexane) of (Ur) was synthesised (Scheme C) from nerolidol (IX) and the trienedial (XI);8 it was identical (spectra stereomutation pattern mixed chromato- gram mixed m.p.) with a fraction isolated from carrot oil. The “central-cis”-isomer (Amax 422 398 378 296 286 mp; vmax.955 doublet 778 cm.-I in cyclohexane) of (111)was synthesised similarly from the acetylenic analogue* of (XI) followed by catalytic reduction of the resulting dehydro-c- carotene (m.p. 68.5-71”; Amax. 409 387 mp; Vma,. 958 cm.? in CHClJ. The “central-cis”-compound had the same visible and infrared light absorption Reagents 1. (i) PBr, (ii) Ph3P (iii) n-BuLi. 2. (i) PBr, (ii) CHMe,NO e/KOH. 4. (i) LiAlH4,(ii) MnO 3. (EtO),PO’CH,‘CMe:CH’CO,Me/NaOMe. 5. (i) MeOCi CMgBr (ii) H+ 6. LIAlH4 f Visible and ultraviolet light absorption spectra were determined for hexane solutions. Nicholaides and Laves J. Amer. Chem. SOC.,1954 76 2596. Isler Riiegg Chopard-dit-Jean Winterstein and Wiss Helv. Chim.Ada 1958 41 786. Mildner and Weedon J. 1953 3294. JULY 1961 ~~~~ ~~ ~~ properties as those reported by Rabourn and Quackenbush for an isomer of (-carotene in carrot oil; this may be the isomer first formed in Nature. The unsymmetrical structure (IV) (A,, 420 395 and 375 mp) was prepared from (VIII) and (XIII); as yet compound (IV) has not been identified in Nature. the structures (XIVb) (XIVc) and (XIVd) respec-tively.1° The suggestedll biosynthetic relationship between these carotenoids and neurosporene (XIVa fV) is now justiiied on structural grounds; the transformations are clearly similar to those involved in the conversion of lycopene into spirilloxanthin.12 Nuclear magnetic resonance spectra (methyl bad only).* Assignments Type of In chain End-of-chain Me group Partial -CH:CHCMe:CH-CH:CH- -CH,CMe:CHCH:CH- Structure Approx.band position 8.06 8.20 Relative number of Me groups Phytoene Phytofluene <-Car0 tene 0 1 2 Neurosporene 3 Lycopene 4 trans-Olehic cis-Olekic Me H Me ,CH2-/\C=C,/ ,c=c 4332 CHZ-CH2 H 8-35 8-40 * The spectra were determined for deuterochloroform or carbon tetrachloride solutions at 56.4 Mc./sec. and calibrated against tetramethylsilane as an internal standard. Band positions are given as 7-values defined by Tiers (J. Phys. Chem. 1958 62 1151). “all-trans”-Neurosporene (m.p. 115-1 16”; Amax 470,440,416mp; vmax. 1631,962 cm.-’ inC Cl,) was synthesised (Scheme D) from $-ionone (XII) and was identical with a sample from Rhodopseudornonas spheroides (spectra mixed chromatogram mixed m.p.).The nuclear magnetic resonance spectra of chloroxanthin pigment Y and pigment R which have also been isolated from these ba~teria,~ lead to 0 The authors are greatly indebted to Dr. W. J. Rabourn for sending them details of his unpublished work with Dr. F. W. Quackenbush on phytofluene and <-carotene. They also thank Dr. Rabourn Dr. M. B. Allen Dr. T. Nakayama Hoffman La Roche and the Nutritional Research Associates Inc. for materials and the D.S.I.R. and Roche Products Ltd. for financial assistance. (Received May 9th 1961.) Goodwin Land and Sissins Biochem. J. 1956 64,486; Nakayama Arch. Bioclzem. Biophys. 1958 75 352 356. lo Barber Jackman Weedon and Yokoyama unpublished work; cf.Barbcr Ph.D. Thesis London 1960. 11 Jensen Cohen-Bazire Nakayama and Stanier Bioclzem. Biophys. Actu 1958 29 477. l2 Barber Jackman and Weedon Pruc. Chem. SOC.,1959 96; Jensen Acta Chem. Scand. 1959,13 381 842 2142 2143; 1960 14,950,953. PROCEEDINGS The Anomalous Magnetic Behaviour and Binuclear Structure of Some So-called Trico-ordinated Copper(@ Complexes C. M. HARRIS B. F. HOSKINS, By G. A. BARCLAY and E. KOKOT (DEPARTMENT CHEMISTRY OF NEWSOUTH OF INORGANIC THE UNIVERSITY WALES BROADWAY AUSTRALIA) SYDNEY KISHITA MUTO and KUBO~ have shown that the copper(I1) complexes (I; R = Me or Ph) and (II) have abnormally low magnetic moments at room temperature (1.1-1.37 B.M. at 287"~). They attribute this to the occurrence of trico-ordinated copper(I1) and possibly direct copper-copper inter- action in the solid state due to dimerisation.For copper(I1) acetate which also has an abnormally low magnetic moment at room temperature and is bi- nuclear,2 Figgis and Martin3 postulated that the electron-exchange demagnetisation is due to the formation of a &bond which involves the overlap of the 3dX2-,,2orbitals of the bridged copper atoms this has been discussed theoretically by Ross.4 The magnetic susceptibility of complex (I) has been measured5 over the temperature range 85-376"~.The agreement between the observed p-Tand Tam p. (K) FIG.1.0 Xm observed. 0 p observed. -Calc. curves. type molecular models suggest that it could possess a binuclear structure containing essentially square- co-ordinated copper(I1) atoms linked by oxygen J J Compound g (ern.?) (kcal.mole-') Cu acetate 270O 2.17 300 0.86 H2O 255 2.13 284 0.82 Y Complex (I; R = Me) 270 2-09 298 0.8 5 Complex (I; R = Ph) 375 2.42 414 1.18 Complex (IT) 265 2.09 293 0.84 Xm-T curves and those calculated from Bleaney and bridges. This was confirmed by crystal structure Bower's expression determination (see Fig. 2). Such a structure is com- patible with the magnetic behaviour since antiferro- g2Np2 Xm = -[I + 1/3 exp (J/kT)]-l + Na magnetic exchange interactions can occur through 3kT the oxygen bridges by means of a superexchange is excellent over the whole temperature range (Fig. mechanism of Kramer type.' l) the curves being similar to those for copper(I1) The crystal structure was determined by three- acetate.6 The close similarity between the T, g and dimensional X-ray analysis of single crystals which J values for this compound and copper(I1) acetate is were obtained from bromobenzene.* shown in the Table.Results Cl1Hl1NO,Cu M = 252.78 triclinic Although it is not possible to formulate complex a = 8-94 b = 10.60 c = 11.76 A cy = 101-1" (I; R = Me) with a structure of copper(I1) acetate = 110*6",y = 93.6",F' = 1020 A3 Dm = 1.67 (by Kishita Muto and Kubo Naturwiss.. 1957,44 372; Austral. J. Chern. 1957,10 386; 1958,11,309. Niekerk and Schoening Acta Cryst.. 1953 6 227. Figgis and Martin J. 1956 3837. Ross Trans. Faraday SOC.,1959 55 1057; Ross and Yates.ibid. p. 1064. Harris and Kokot unpublished work. Bleaney and Bowers Proc. Roy. SOC.,1952 A 214,451. Kramers Physics 1934 1 182; see also Anderson Phys. Rev.,1950 79 350. Barclay and Hoskins unpublished work. JULY 1961 flotation) 2 = 4 Dc = 1.65 g. ~m.-~ space group fi (C!; No. 2) Cu-radiation unfiltered single- crystal oscillation and Weissenberg photographs. From the three-dimensional Patterson function calculated from 2300 independent reflections ap- proximate co-ordinates were obtained for the 30 atoms in the asymmetric unit (Le. all atoms other than hydrogen). The co-ordinates were confirmed by a three-dimensional Fourier synthesis and refined by differential syntheses. The present R-value based on observed reflections only is 0.15.The crystal is built up from dimers of C,,H,,CuNO units. The bond lengths at the present stage of the refinement are shown in Fig. 2. The estimated standard deviations of the copper- copper copper-light atom and light atom-light atom distances are about 0.005,0.02,and 0.03 A respectively. The two copper atoms in the molecule have different environments. One of them Cu(2) has a distorted square-pyramidal co-ordination with the O(4) atom of another molecule at 2.68 8 along a line approximately normal to the Cu(2)-0(2)-0(3)-0(4)-N(2) plane. The other Cu( l) has a square-planar co-ordination with no atom from neighbouring molecules closer than 3.5 A. The variations in the copper-oxygen distances in the bridge are probably due to the interaction between Cu(2) and O(4') atoms.1-33 p=q.3* FIG.2. The other magnetically anomalous compounds (I ; R = Ph) and (11) probably possess a binuclear bridged structure also. Their Tc,g and J values are listed in the Table. To our knowledge complex (I; R = Me) is the first reported copper(I1) complex which behaves magnetically like copper(I1) acetate but does not possess a copper(I1) acetate type of structure. (Received May 15th 1961.) The Pyrolytic Decomposition of Maytenone A Model System By C. P. FALSHAW and T. J. KING A. W. JOHNSON (UNIVERSITY OF NOTTINGHAM) IT has been proposedl that the bis-diterpene maytenone (I) on pyrolysis undergoes a concerted rearrangement leading to the formation of propene podo~arpane-6,7-diol,~ C1,HZ4O2(11; R = H) and by a 1,2-migration of an isopropyl group 6-hydroxy- totarol? C20H3,02 (11; R = CHMe,).In order to test this hypothesis we have oxidised 4-methyl- thymo14 (111) with sodium metaperiodate and found that the 2-hydroxycyclohexadienone(IV) which was formed initially underwent self-addition of Diels- Alder type to give the dimer for which (V) is a probable representation (cf. ref. 5). The infrared spectrum of the dimer (V) closely resembled that of maytenone,l and like maytenone the dimer decomposed at 190"with the evolution of Johnson King and Martin J. 1961 in the press. Hill Johnson and King J. 1961 in the press. Elmore and King J. 1961 in the press. Clemmensen Ber. 1914 47 51.a gas. This temperature is slightly higher than that required for decomposition of maytenone and gas chromatography showed that although the gas was mainly propene it also contained smaller quantities of methane ethane and ethylene. The amount of gas evolved was appreciably less than one mol. of propene (45 % by weight loss ;25 % by volume). The main products from the pyrolytic decompos- ition were two catechols identified by chromato- graphy on paper as 4,s-dimethyl- and 3-isopropyl- 4,5-dimethyl-catechoI (VI; R = H R' = CHMed although only the latter could be isolated as the crystalline dibenzoate from the reaction mixture. This dibenzoate has been identified by direct com- parison with a synthetic sample prepared from Adler Junghahn Lindberg Berggren and Westin Actu Gem.Scand. 1960 14 1261. x =CHMe 2,3-dimethoxy-5,6-dimethylbenzoic acid6 (VI; R = Me R' = C02H) (C0,H-t C0,Me 3CMe=CH +CHMe, followed by demethylation and benzoyl- ation). It is evident that the isopropyl group has migrated during the decomposition and the reaction is thus a rare example of a 1,2-alkyl shift brought about by heat alone. Pyrolysis of the dimer (V) thus proceeds qualita- PROCEEDINGS tively in a manner similar to that of maytenone. Quantitatively however the reactions differ in that the two catechols and propene are produced in roughly equimolecular proportions from maytenone whereas in the case of the dimer (V) the aromatisa- tion involving rearrangement occurs to a greater extent than the aromatisation involving elimination.' Thus the dimer (V) cannot decompose under the experimental conditions cited by an overall con- certed mechanism and it is probable that the initial step is a reversed Diels-Alder reaction leading to the dienone (IV) which then rearranges to the catechols in the manner found.It is possible that reactions of the type described are significant in Nature and that some terpenes which do not obey the isoprene rule are formed in this manner. Thus if we assume that the 4-methyl- thymol transformations are analogous to those of maytenone the latter compound although it is known to give rise to a non-isoprenoid totarol deriva- tive (11; R = CHMe,) by decomposition can never- theless be derived biogenetically by oxidation of the isoprenoid ferruginol (VII).Experiments to test the possibility of preparing maytenone by the oxidation of ferruginol are in progress. (Received May 30th 1961.) Bruce and Sutcliffe,J. 1956. 3824. Cf. Conradi and McLren J. Amer. Chem. SOC.,1960 82 4745. NEWS AND ANNOUNCEMENTS Election of Honorary Fellows.-The Council elected the following to Honorary Fellowship on June 8th 1961 Sir Howard Florey (Oxford) ; Professor Henry Gilman (Iowa) ; Professor Alexander Nicolai Nesmeyanov (Moscow); Professor Vlado Prelog (Zurich). Local Representatives.-Dr. E. H. P. Young has been appointed Local Representative for Manchester in succession to Dr. J. Honeyman who has resigned. Research Fund.-The Research Fund of the Chem- ical Society provides grants for the assistance of research in all branches of Chemistry.Applications for grants will be considered in November next and should be submitted on the appropriate form not later than Wednesday November 15th 1961. Applications from Fellows will receive prior con- sideration. Reports on grants outstanding from previous years should be made by November 1st. Forms of application together with the regulations governing the award of grants may be obtained from the General Secretary. The Henry Dale Professorship of the Royal Society.-The Council of the Royal Society has warmly accepted a generous gift of €100,0oO from the Trustees of the late Sir Henry Wellcome to establish and endow a Royal Society Professorship in Medical Research to be known as The Henry Dale Professorship.The Wellcome Trustees have made this gift to commemorate the unique services of Sir Henry Dale O.M. G.B.E. F.R.S. to their Trust as its Chairman for 22 years as well as his out- standing contributions to science and medicine in a wider context. In accepting the gift the Society ex- presses its gratitude and great satisfaction in being associated with the Trustees in this act of honouring its distinguished Fellow Sir Henry Dale who has also rendered conspicuous service to the Society both as Secretary (1925-35) and as President (1940-45). The Council of the Royal Society greatly values this outstanding benefaction which will significantly increase the Society's capacity to promote medical research.The appointments to the new Professorship will be especially but not necessarily exclusively in relation to research in physiology and pharmacology JULY 1961 which are the particular interest of Sir Henry Dale. U.S.S.R. Academy of Sciences.-Academician A. N. Nesmeyanov has resigned as President of the U.S.S.R. Academy of Sciences after holding office for more than ten years. He has been succeeded by Academician M. Keldysh. Research Association for Rubber and Plastics Industries.-To meet the rapidly increasing techno- logical demand of the nation’s plastics industry the former Research Association of British Rubber Manufacturers has extended the scope of its activities during 1961 under the new title of the “Rubber and Plastics Research Association of Great Britain” in order to cover the requirements of both the rubber and the plastics industries.The new joint research association is a logical move as the science and technology of these in- dustries have much in common. The idea has since been widely accepted by the two industries and has received active support from members of the former Research Association of British Rubber Manufac- turers and of the British Plastics Federation. The Department of Scientific and Industrial Research has also welcomed this move and has agreed to grant the new research association up to S77,000 provided industry itself raises f120,O in each of the three years 1961-63.Symposium on Electron-spin Resonance.-The Chemical Society will hold a symposium at Queen Mary College on Thursday November 2nd 1961 starting at 2 p.m. The provisional list of speakers is as follows Professor H. C. Longuet-Higgins F.R.S. Univer- sity of Cambridge. “General Introduction.” Prof. S. 1. Weissman University of Washington. “Molecular Association and Rates of Electron Transfer.’’ Prof. D. J. E. Ingram University College of North Staffordshire. “Structural Analysis by Electron Resonance.” Dr. J. R. Bolton and Dr. A. Carrington University of Cambridge. “E.S.R. Spectra of the Toluene p-Xylene and m-Xylene Anions.” Dr. E. A. C. Lucken Cyanamid European Re- search Institute Geneva. “Spin Densities in Semi- quinones.” Prof.M. C. R. Symons University of Leicester. “Radiation Damage in Some Inorganic Oxy-salts.” Dr. J. R. Morton National Physical Laboratory Teddington. “E.S.R. Spectrum of Irradiated a-Alanine down to 77”~.” Full details and times will be issued later. International Congresses etc.-The 12th Sym- posium on Corrosion in Nuclear Technology sponsored by the European Federation of Corrosion will be held in Paris on October 19-20th 1961. Enquiries should be addressed to the SociCt6 de Chimie Tndustrielle 28 rue Saint-Dominique Park 7e France. A Symposium on Sintered High-temperature Oxidation-resistant Materials will be held in London on December 7-8th 1961. Enquiries should be addressed to Lt.-Col. S. C. Guilan Secretary Powder Metallurgy Joint Group Institute of Metals 17 Belgrave Square London S.W.l.An International Conference on Natural Rubber Research will be held in Paris in May 1962. En- quiries should be addressed to the Secretary-General Institut FranGais du Caoutchouc 42 rue Scheffer Paris 16e France. European Corrosion Conference sponsored by the European Federation of Corrosion will be held in Paris in June 1962 on the occasion of the 6th Exhibition of Chemistry (Salon de la Chimie). Enquiries should be addressed to the SociCtC de Chimie Industrielle 28 rue Saint-Domhique Paris 7e France. A Symposium in Commemoration of the Fiftieth Anniversary of the Discovery of X-Ray Diffraction and of Crystal Structure Analysis will be held in Munich on July 24-27th 1962.Enquiries should be addressed to D. W. Smits General Secretary Inter- national Union of Crystallography c/o Mathe matisch Institut University of Groningen Reit- diepskade 4 Groningen Netherlands. A Symposium on Organometallic Complexes will be held in Brussels in August 1962. Enquiries should be addressed to ComitC National de Chimie Palais des AcadCmies Brussels Belgium. An lnternational Symposium on Pharmaceutical Products will be held in Florence on September 17-19th 1962. Enquiries should be addressed to Professor A. Soldi Segretaria Societh Italiana di Scienze Pharmaceutiche Via Giorgio Jan 18 Milan Italy. The First International Congress of Food Science and Technology will be held in the Imperial College of Science and Technology London on September 18th-21st 1962.Enquiries should be addressed to the Honorary Secretary of the Congress 14 Belgrave Square London S.W. 1. Election of New Fellows.-67 Candidates whose names were published in Proceedings for May have been elected to the Fellowship. Deaths.-We regret to announce the deaths of the following Mr. P.S. Allam (29.4.61) Patent Agent of London W.C.2; H. Harris (23.5.61) Worthing a Fellow for over 65 years; Mr. R. A. McNicol (12.4.61) Supervising Chemist J. Lyons and Com- pany Limited; and Mr. C. H. Wordsworth (1.6.61) Public Analyst of London E.C. 1. The title of Reader in Organic Chemistry in the University of London has been conferred on Dr. 7‘.G. Bonner in respect of his post at Royal Holloway College.Dr. K. C. Campbell Dr. I. C. McNeilI and Dr. A. L. Forte have been appointed Lecturers in Chemistry at The University of Glasgow. Dr. B. E. Conway Professor of Chemistry in the University of Ottawa will be visiting the Institute of Electrochemistry in Moscow for three months under the scientists’ exchange programme of the National Research Council and the Academy Bf Sciences Moscow. The title of “Professor of Organic Chemistry in the University of London” has been conferred on Dr. Alexander Lawson in respect of his post at the Royal Free Hospital School of Medicine. Professor W. H. Linnell is to retire from the Chair of Chemistry of the University of London tenable at the School of Pharmacy in September next.Dr. W. B. Whalley has been appointed to succeed him. Dr. R. Long formerly Senior Research Chemist with Borax Consolidated Limited has been ap-pointed technical officer with Imperial Chemical Industries Limited Heavy Organic Chemicals Division Billingham. Dr. T. F. Macrea has received the Honorary Degree of LL.D. of the University of Glasgow. Dr. I. T. Millar Lecturer in Chemistry at the University College of North Staffordshire has been appointed Senior Lecturer from October 1 st next. Dr. R. B. Moodie has been appointed Lecturer in Chemistry at Exeter University from October lst 1961. Professor D. M. Newitt has been appointed a part-time Director of Albright and Wilson Limited. Dr. D. F. Rushman Chief Chemist of the Kay group of companies has been appointed a Director of Kay Brothers Limited of Stockport Kay Brothers PROCEEDINGS Plastics Limited and Kay Brothers (Ireland) Limited.The University of Aligarh has awarded the degree of D.Sc. in Chemistry (Organic) to Dr. G. S. Saharia for his work on the chemistry of alicyclic rings especially the six- and seven-membered and the mechanism of the Fries reaction. Dr. B. L. Shaw has been appointed Lecturer in the Department of Inorganic and Structural Chemistry at The University of Leeds from January 1st next. Dr. F. G. A. Stone Assistant Professor in Harvard University has been appointed to the University Readership in Inorganic Chemistry tenable at Queen Mary College. Mr. G. V. Taylor retired in June as Works Manager at the Newport factory of Monsanto Chemicals Limited.Dr. James Taylor a Director of Imperial Chemical Industries Limited has been appointed to the Board of Pyrotenax Limited. Dr. C. F. H. Tipper has been appointed Senior Lecturer in inorganic and physical chemistry at the University of Liverpool. Sir Alexander Todd has been elected Master of the Salters Company for the year 1961-62. He received the Honorary Degree of D.Sc. from the University of Yale on June 12th. Prqfessor F. L. Warren has been awarded the South Africa Medal for 1961 by the South African Association for the Advancement of Science. Dr. D. E. Wheeler Managing Director of the Wellcome Foundation Limited has been re-elected Vice-President of the Association of the British Pharmaceutical Industry.Dr. W.Wild has been appointed Head of the Chemistry Division of A.E.R.E. Hanvell. Mr. A. A. Smales has been given the status of a Division Head and will be directly responsible to the Director for the scientific work under his control. FORTHCOMING SCIENTIFIC MEETINGS East Africa Lecture “The Biogenesis of Isoprenoid Com-pounds,” by Dr. T. G. Halsall F.R.T.C. to be held as follows Friday August 11 th at 5.30 p.m. in the Department of Chemistry Makerere College Kampala. (Joint meeting with the Royal Institute of Chemistry.) Wednesday August 16th at 5.15 p.m. in the Norfolk Hotel Nairobi. (Joint meeting with the Royal Institute of Chemistry and the Nairobi Scientific and Philosophical Society.) JULY 1961 269 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.) Baverstock Maureen Anne B.%. 14 Vinery Gardens Shirley Soutkampton Hants. Brieger Gottfried B.A. Ph.D. Chemistry Department University of Wisconsin Madison Wisconsin U.S.A. Chasseaud Leslie Frank. Wyle Lodge Cobbets Hill Weybridge Surrey. Clarke Clifford Brian Ph.D. 29 Speke Hall Road, Liverpool 24. Colbran Richard Lund B.Sc. 409 Manchester Road Burnley Lancs.Cotton John Douglas B.Sc. Trinity College University of Melbourne Parkville N2 Victoria Australia. Cutmore John Richard. 34 Panfield Lane Braintree Essex. Deshpande Vasant Virupax M.Sc. Ph.D. A.R.I.C. Department of Chemistry Imperial College of Science and Technology London S.W.7. Drake Edgar Nathanial B.S. 2030 Athens Apt. H Boulder Colorado U.S.A. Dube Shyam Kumar M.Sc. Ph.D. Chemistry Depart- ment Kansas State University Manhattan Kansas U.S.A. Fish Kenneth Ph.D. 92A Claypath Durham. Fisher Farley S.B. 219 Noyes Laboratory University Of Illinois Urbana Illinois U.S.A. Forstner James Allan M.S. Chemistry Department Carnegie Institute of Technology Pittsburgh 13 Pennsylvania U.S.A. Gerdil Raymond Dr* “. sc. 53 rue du Grand pr‘, Geneva Switzerland.Ginsberg Alvin Paul A.M. Ph.D. Bell Telephone Laboratories Murray Hill New Jersey U.S.A. Henderson Ian Woolton Hall Fallowfield Manchester 14. Hiddleston James Norman. 8 Warendon Crescent High Barnes Sunderland Co.Durham. Holt Donald. 96 Sutton Road Muswell Hill London N.lO. Hughes Brian. 331 Worsley Road Swinton Lancs. Juneja Hari Ram M.Sc. Chemistry Department The University Manchester 13. Liu Kwang-ting B.S. Department of chemistry, National Taiwan University Taipei Taiwan (Formosa) China. McClelland Euan. 81 Poppleton Road York. McGrew Berenice B.S. Department of Chemistry, Carnegie Institute of Technology Pittsburgh 13 Pa, U.S.A. Martin Patricia Ann B.Sc. 103 Barnsole Road Gilling- ham Kent.O’Keeffe Michael Ph.D. Department of Chemistry, Indiana University Bloornington Indiana U.S.A. Outcalt Mark C. B.S. Department of Chemistry Purdue University Lafayette Indiana U.S.A. Reasoner John William B.S. Chemistry Department Iowa State University Ames Iowa U.S.A. Robinson Thomas Alexander B.Sc. 66 University Street Belfast 7 N. Ireland. Rowlands John Rhys Ph.D. 25 School Road Ashford Middx. Schaeffer Riley Ph.D. 415 N. Lincoln Street Blooming- ton Indiana U.S.A. krwo ~010.Institute di Chimica Fisica Via Risorgi- mento Pisa Italy. Silva Ricardo Augusta Ph.D. Organic Chemistry Department Imperial College of Science and Tech- nology London S.W.7. Slade Michael B.%. 39 Hillway Avenue San Francisco 17, Taniewski Marian D.Sc.Tech. Barlickiego 9/2. Gliwice ”land-Weeks Albert Edwin M.P.S. 39 High Cross Road Rogerstone Newport Man-Whipple Richard Ogborn M.S. 61 Los Cerros Place Walnut Creek California U.S.A. Yunker Wayne Harry Ph.D. 205 N. 32nd Street, Corvallis Oregon U.S.A. OBITUARY NOTICE CHARLES EDWARD KENNETH MEES 1882-1 C. E. KENNETH MEES the most outstanding of photographic scientists and pioneer of industrial research died in Honolulu Hawaii on August 15th 1960 aged 78. He was born at Wellingborough on May 26th 1882 the son of a Wesleyan Minister and was educated at Kingswood School Bath and at St Dunstan’s College in South East London. Here he formed a close friendship with S. E. Sheppard which lasted until Sheppard’s death in 1948.Sheppard and Mees worked together at University College London under Sir William Ramsey. It was possible at the turn of the century to obtain a B.Sc. of 960 London University by research and the choice of photography as a subject gave rise to considerable opposition from the more orthodox professors. However Ramsey’s influence was instrumental in obtaining final acceptance and Sheppard and Mees obtained B.Sc. by research in 1903 and D.Sc. in 1906. Their theses published under the title “Investigations on the Theory of thePhotographicProcess,” became a standard text book familiarly known as “Sheppard and Mees.” Sheppard continued academic research in Ger- many but Mees was with some difficulty dissuaded from this course by Ramsey who convinced him that his metier was in applying science to industry.Accordingly Mees joined the photographic firm of Wratten and Wainwright as Partner and Joint Managing Director an exalted position which carried with it the stipend of f3 per week! Here Mees spent six happy years continuing his researches and taking an active part in organised photography-he became Vice-president of the Royal Photographic Society in 1912 and would undoubtedly have been its youngest President had he remained in England. But the most valuable asset of his six years’ experience with Wratten and Wainwright was the insight which he gained in research applied to commercial ends and his characteristic attitude towards it. This is illu- strated by an early experience when because of cut prices and reduced profits Mees was asked to devise methods of reducing the manufacturing costs of photographic plates.Instead he devised methods of incorporating sensitising dyes during manufacture and the firm marketed the first panchromatic plates at a premium price and at a satisfactory profit. As most of the photographic advances at the time were empirical Mees had an almost clear field in applying science to the industry and during his first year he devised the Wratten series of filters and safelights which were a considerable advance on competitive products. Later he marketed special plates for photo-engravers astronomers and spectroscopists. About this time George Eastman had come to the conclusion-unusual in those days-that the future prosperity of his Company depended on the estab- lishment of an industrial research laboratory and the one obvious choice for its leader was the brilliant young man in England who had established an inter- national reputation for photographic research and for the products of Wratten and Wainwright.East- man accordingly came to London and invited Mees to set up a Kodak Research Laboratory in Rochester N.Y. The invitation appealed greatly to Mees but he did not feel justified in leaving the firm in which he had worked happily for six years. Eastman’s solution to the impasse was characteristic-he bought the firm of Wratten and Wainwright. During his first year or so in Rochester N.Y. Mees became extremely homesick and resolved to return to London at the first opportunity.However this phase passed and he settled down to organise the research laboratory. Many of its members including S. E. Sheppard were brought from England and his own experience decided his policy of acclimatisation. After a year’s work in Rochester during which the men invariably decided to return to England Mees gave them a few months holiday in England during which the consistent pattern was a contented return to work in Rochester. Eastman and Mees had much in common-energy PROCEEDINGS farsightedness and ingenuity-and Mees continued Eastman’s policy of improving and cheapening photography so as to make it more suitable for the general public as well as for the expert.This in- volved continuously opening up new markets with new products and Mees’ two major contributions to amateur photography were home movies (16 mm. and 8 mm.) and colour photography. Partly through Mees’ influence the Eastman Kodak Company began to interest itself in extra- photographic activities. The first opportunity arose when the U.S.A. entered the First World War and the supplies of German sensitising dyes were cut off. Mees made a round of American chemical firms but he was unsuccessful in persuading them to manu- facture the dyes-doubtless they were fully occupied at the time. He then made a second round informing them that unless manufacture was undertaken by a chemical firm Kodak would be forced to enter the organic chemical field.Again he met with no success and so commenced the manufacture of Eastman organic chemicals now the widest range marketed by any firm.Mees was mildly amused when after organic chemical production had been firmly estab- lished he was quietly approached by one chemical firm after another with an offer to reconsider their refusal to manufacture chemicals for Kodak. In 1923 Eastman established a factory at Kings- port Tennessee for the manufacture of cellulose acetate for film base. Film base is an expensive item and its price could be considerably reduced if it were manufactured in much larger quantities and an outlet found for the remainder. This introduced Kodak into the plastics field. The wide range of cellulose ester moulding powders fibre yarn and sheet film led to the production of other plastics and of dyes suitable for cellulose esters.Hitherto the activities had been the logical outcomes of previous work but when the writer asked why Kodak was engaging in the manufacture of vat dyes unconnected with plastics Mees replied with a wry smile “Just greed” ! He was never anxious to keep power in his own hands and on several occasions split off sections of the Research Laboratory when their function had become control rather than research. He also estab- lished Research Laboratories at Harrow (England) and Vincennes (France) and having done so characteristically gave them virtual autonomy. Mees gave his staff enormous latitude in choosing subjects for research many of which seemed to have no connection with photography.Indeed one of his dicta was that the main function of a Research Director is to protect his men from those who wish to direct their research. On one occasion the writer asked Mees whether he would place any limit on the JULY 1961 type of research done by his staff. He replied that if a keen motorist on his staff wished to do research on the internal combustion engine Mees might suggest that a more suitable institution for such work could be found. Such liberality has been financially most rewarding the best example making a most interest- ing story. Among the bright young Englishmen en- gaged by Mees was C. D. K. Hickman who was given the job of studying residual solvents and plasticers in film base.Hickman thought that mole- cular distillation might be the best means of tackling the problem. Indeed he became one of the leading authorities in the technique and completely lost sight of the original object. While in a druggist’s it occurred to Hickman that vitamins might be separated from cod liver oil (and from its obnoxious taste) by molecular distillation. Successful experiments led to the establishment of a subsidiary company Distillation Products Industries now one of the world’s largest manufacturers of vitamins and other related products. Mees always maintained that industry’s debt to science should be repaid and he commenced the policy of supplying material for bona fideresearch at nominal prices even though some of it was fabu- lously expensive to produce.He also insisted on the publication of fundamental research and to date the associated laboratories of the firm have published some 2,100 scientific communications Mees being the author of about 150. His most important pub- 27 1 lished work was “The Theory of the Photographic Process,” to which experts throughout the Kodak organisation contributed. It first appeared in 1942 and was revised in 1954 and is the most authorita- tive and comprehensive book on photographic science in existence. His other books show the range of his interests. They include “The Organisation of Industrial Scientific Research,” first published in 1920 and revised in collaboration with J.A. Leermakers in 1954. His general philosophy on science is illustrated in “The Path of Science,’’ 1946. His work gained for him rapid promotion in the Company (in 1923 he was made a director and in 1934 Vice-president) and the highest honours from scientific bodies culminating in the Fellowship of the Royal Society in 1939. He had an astonishing breadth of knowledge and this combined with a very forceful personality and power of expression made him dominate any discus- sion group. Consequently in his youth he was apt to antagonise his seniors and later in life to terrify his juniors. This phase did not last long and invariably turned into a warm friendship which among his closer colleagues became a deep affection. In 1909 Mees married Alice Crisp who died in 1954.He is survived by a son Graham C. Mees President of Distillation Products Industries Division of the Eastman Kodak Co. and by a daughter Mrs. R. S. Sturdy of Bletchley Bucks. H. BAMES. ADDITIONS TO THE LIBRARY Louis Pasteur a master of scientific enquiry. J. Nicolle. Pp. 196. Hutchinson. London. 1961. Radioisotope data. R. A. Allen D. B.Smith and J. E. Hiscott.A.E.R.E.-R.2938.2ndedn.Pp. 199.U.K.A.E.A. Isotope Research Division. Wantage Berkshire. 1961. The production of chemicals from reactors. Part 5. Ethylene glycol from the pile (n + t) and fission fragment irradiation of liquid methanol. D. A. Landsman and J. E. Butterfield. A.E.R.E.-R.3625. Pp. 25. A.E.R.E. Harwell Berks. 1961. An index of published infra-red spectra.Edited by Ministry of Aviation Technical Information and Library Services. 2 vols. Pp. 805. H.M.S.O. London. 1960. Tables of wavenumbers for the calibration of infra-red spectrometers. Compiled by the International Union of Pure and Applied Chemistry Commission on Molecular Structure and Spectroscopy. Pp. 699. Butterworths. London. 1961. (Presented by the publisher.) Crystallisation. J. W. Mullin. Pp. 26. Butterworths. London. 1961. Thermodynamics. G. N. Lewis and M. Randall. Revised by K. S. Pitzer and L. Brewer. 2nd edn. Pp. 723. McGraw-Hill. New York. 1961. Thermodynamic functions of gases. Edited by F. Din. Vol. 3. Pp. 218. Butterworths. London. 1961. Modern aspects of the vitreous state. J. D. Mackenzie. Vol.1. Pp. 226. Butterworths. London. 1960. Electrolytic dissociation. C. B. Monk. Pp. 320. Academic Press. London. 1961. Paper electrophoresis a review of methods and results. L. P. Ribeiro E. Mitidieri and 0. R.Monso. Pp. 463. Elsevier. Amsterdam. 1961. Physical chemistry of the deposition of thin films on moving bases. B. V. Deriagin and S. M. Levi. (InRussian.) Pp. 206. Akad. Nauk. S.S.S.R Moscow. 1959. (Presented by the authors.) Modem inorganic chemistry. J. W. Mellor. Revised and edited by G. D. Parkes. 5th edn. Pp. 1024. Longmans. London. 1961. Synthetic inorganic chemistry. W. L. Jolly. Pp. 196. Prentice-Hall International Inc. London. 1961. Inorganic reactions and structure. E. S. Gould. Pp. 470.Holt Rinehart and Winston. New York.1955. Nouveau trait6 de chimie min6rale. Edited by P. Pascal. Vol. 13 Parts 1 and 2. Pp. 2146. Masson et Cie. Paris. 1961. (Presented by the publisher.) The theory of transition-metal ions. J. S. Griffith. Pp.455. C.U.P. Cambridge. 1961. Cobalt its chemistry metallurgy and uses. Edited by R. S. Young. (A.C.S. Monograph Series No. 149.) Pp. 424. Reinhold. New York. 1961. Silicon and its binary systems. A. S. Berezhnoi. (Translated from the Russian.) Pp. 275. Consultants Bureau. New York. 1960. X-Ray analysis of Organic structures. S. C. Nyburg. Pp.434. Academic Press. New York. 1961. Neuere Methoden der Praparativen Organischen Chemie. Edited by W. Foerst. Vol. 2 and 3. Verlag Chemie. Weinheim. 1960-61. Preparative methods of polymer chemistry.W. R. Sorenson and T. W. Campbell. Pp. 337. Interscience Publishers Inc. New York. 1961. Polynucleotides natural and synthetic nucleic acids. R. F. Steiner and R. F. Beers jun. Pp. 404. Elsevier. Amsterdam. 1961. BIock and graft polymers. W. J. Burlant and A. S. Hoffman. Pp. 166. Reinhold. New York. 1961. A simple apparatus for the gas chromatography of polyphenyls. R. W. Wilkinson and J. A. Winter. A.E.R.E.-M.820. A.E.R.E. Harwell Berks. 1961. Industrial organic nitrogen compounds. M. J. Astle. (American Chemical Society Monograph Series No. 150.) Pp. 392. Reinhold Publishing Corporation. New York. 1961. Cigarette smoke condensate preparation and routine laboratory estimation. H. R. Bentley and J. G. Burgan.Tobacco Manufacturers Standing Committee Research Papers. No. 4.2nd edn. Pp. 14. Tobacco Manufacturers Standing Committee. London. 1961. (Presented by the publisher.) Activation analysis handbook. R. C. Koch. Pp. 219. Academic Press. New York. 1960. 1960 Book of A.S.T.M. Methods for Chemical Analysis of Metals formulated by the Committee E-3 on Chemical Analysis of Metals and Committee E-2 on Emission Spectroscopy. Pp. 765. A.S.T.M. Philadelphia. 1961. Spectrochemical analysis a treatise on the dc arc analysis of geological and related materials. L. H. Ahrens and S. R. Taylor. 2nd edn. Pp. 454. Pergamon Press. London. 1961. Semimicro qualitative organic analysis ;the systematic identification of organic compounds. N. D. Cheronis and J.B. Entrikin. 2nd edn. Pp.774. Interscience Publishers Inc. New York. 1960. Microanalysis by the ring oven technique. H. Weisz. Pp.112. Pergamon Press. Oxford. 1961. Recent advances in biochemistry. T. W. Goodwin. 4th edn. Pp. 301. Churchill. London. 1961. Moisture determination by the Karl Fischer reagent. Pp. 15. British Drug Houses Laboratory Chemicals Division Poole. 1961. (Presented by B.D.H.) High vacuum technique theory practice industrial applications and properties of materials. J. Yarwood. Pp.208. Chapman & Hall. London. 1961. The biological role of ribonucleic acids. J. Brachet. 6th Weizmann Memorial Lecture Series. 1959. Pp. 144. Elsevier. Amsterdam. 1960. Fundamentals of radiobiology. Z. M. Baco and P. Alexander.2nd edn. Pp. 555. Pergamon Press. Oxford. 1961. The behaviour of plasticizers. I. Mellan. Pp. 273. Pergamon Press. Oxford. 1961. Pulp and Paper. J. P. Casey. Vol. 3. 2nd edn. Inter- science Publishers Inc. New York. 1961. Introduction to natural and synthetic rubbers. D. W. Huke. Pp.16. Hutchinson. London. 1961. Fertilizers in Europe production consumption prices and trade. 10th study 1958-1961. Pp. 97. O.E.E.O. Paris. 1961. (Presented by the publisher.) Gas chromatography proceedings of the second International Symposium on Gas Chromatography held at the Kellogg Center Ann Arbor Michigan 1959; under the auspices of the Analysis Instrumentation Division of the Instrument Society of America. Edited by H. J. Noebels R. F. Wall and N. Brenner.Pp.463. Academic Press. New York. 1961. Size and shape changes of contractile polymers pro- ceedings of Seminars held at University College London. Edited by A. Wassermann. Pp. 118. Pergamon Press. Oxford. 1960. The mechanism of heterogeneous catalysis :proceedings of a symposium held in Amsterdam 1959. Edited by J. H. de Boer. Pp. 179. Elsevier. Amsterdam. 1960. Special ceramics proceedings of a symposium held at the British Ceramic Research Association 1959. Edited by P. Popper. Pp.369. Heywood. London. 1960. Pressure-gasification with oxygen of solid fuels in Germany. H. Weittenhiller. Pp. 9. Hydrogen sulphide removal by the Stretford liquid purification process. T. Nicklin and E. Brunner. Pp.22. Papers read at the 98th annual general meeting of the Institution of Gas Engineers held in London 1961.Institution of Gas Engineers. London. 1961. (Presented by the publisher.)
ISSN:0369-8718
DOI:10.1039/PS9610000229
出版商:RSC
年代:1961
数据来源: RSC
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