new books - ACS Publications

---

NEW BOOKS Organic Chemistry for Advanced Students. Julius B . Cohen. Vols. I , 11, I I I . Fifth edition. $1 X 16 em; p p . hi @8; p p . wii 487; p p . vii 440. N e w Y o r k : L o n g m a n s , Green a n d Co.; London: E d w a r d Arnold a n d Co., 1928. Price: 86.00 per volume. I n the preface, p. iii, the author says: “The last decade has seen an unusual development of organic chemistry, more especially in this country, where the additional facilities and inducements for posegraduate research, afforded by grants and research scholarships from public funds, has resulted in a bewildering accumulation of new facts and new ideas. I t follows that the student desirous of making himself familiar with the more important advances in the subject may waste much of his valuable time in trying to winnow the chaff from the grain. “The object of the present edition is to bring the various topics up to date whilst retaining an account of their early history. By condenaing some of the less important sections, and by eliminating other portions, which have been superseded by subsequent research, the size of the present edition is only slightly larger than the last.” The first volume is devoted to reactions and the chapters are entitled: historical introduction; valency of carbon; nature of organic reactions; dynamics of organic reactions; abnormal reactions. The author speaks, very properly, of radicals, and says, p. I , that “it is a n interesting and curious fact that, with admittedly ‘little to recommend it’, the Chemical Society of Great Britain has seen fit to alter the original spelling to ‘radicle,’ and the Society now holds the unique position of being the only representative body of chemists which has adopted this spelling.” It must be said, however, that the Chemical Society no longer insists that esters shall be called ethereal salts. “Gomberg and his eo-workers have shown by comparing careful molecular weight determinations of various triarylmethyls that with changes of temperature and of dilution in various solvents change of colour does not run parallel with dissociation and that consequently the colour change must be attributed to tautomerism between a benzenoid and quinoid form,” p. 63. “A number of recent observations appear to indicate that nitrogen may exist in a quadrivalent form. The formation of a deep blue colour has been noticed when alkyl or acyl pyridyls are reduced. These blue solutions on absorbing oxygen are decolourised and it was consequently assumed that the blue colour was due to compounds containing bivalent nitrogen. Further investigation has however made it clear that the substances are dipyridyl derivatives, though there is a difference on the part of different observers in the interpretation of the facts. Dimroth regards these compounds as possessing the structure of a quinhydrone, consisting of two dipyridyl groups. Weitz, on the other hand regards them as monomolecular dipyridyl compounds. Emmert inclines to the quinoid formula. “Khen a solution of a tetralkylammonium iodide in liquid ammonia is electrolysed or when the chloride is acted on by metallic potassium, a blue solution is formed which reacts in many respects like a solution of the alkali metals in the same solvent. For example, it gives a characteristic deep yellow with dimethylpyrone which is scarcely distinguishable from dimethyl pyrone potassium. Schlubach regards the blue compound as the free ammonium radical, which therefore contains quadrivalent nitrogen,” p. 66. “There are a number of compounds in which there is reason to believe that bivalent carbon is present. Among these are carbon monoxide, CO; fulminic acid, C:NOH; and, according to Xef, the alkyl and acyl isocyanides, RXiC, and acetylene and its halogen derivatives. Although it is possible to interpret the structure of all these compounds, except the last, as containing mutually saturated valencies by making oxygen quadrivalent or nitrogen quinquevalent, there are chemical as well as stereochemical considerations which

+

+

+

NEW BOOKS

I435

make such a supposition improbable. If we accept the usual stereochemical arrangement of the carbon bonds, it is difficult to conceive of these four linkages being brought simultaneously into action with any other single atom. The chemical properties of most of these compounds point in the same direction,” p. 68. “By a n unsaturated group, as distinguished from an unsaturated atom, we wish to imply the union of two atoms whose affinities are not saturated. When the union lies between carbon and carbon we obtain the unsaturated hydrocarbons and their derivatives. It is clear that in a case of this character, as, for example, in ethylene and acetylene, we may indicate unsaturation in several ways. Adopting Werner’s view that valency may distribute itself unequally over the atom, a larger amount will be available for uniting unsaturated than for saturated carbon, or unsaturation may be indicated by the union of bivalent or tervalent carbon atoms, leaving a certain amount of affinity free, or, again, the unsaturated valencies may be represented by the method adopted by Kef in bivalent carbon compounds, as saturating one another. I n the last case we obtain what are known as double or treble bonds or linkages. Although the double and treble bond is very generally accepted, it may be well t o state briefly the evidence upon which it rests. We will then proceed to discuss the theory of free valencies, Le. the union of bivalent and tervalent carbon, and finally Kerner’s theory in its application to unsaturated compounds,” p. 77. “The union of ethylene and bromine is almost inhibited in a vessel coated with paraffin wax, whereas a glass surface allows the reaction to proceed, and is further accelerated by a stearic acid film. The effect is ascribed to the presence in the latter cases of a polar catalyst,” p. 126. “ 4 more comprehensive theory of catalysis which has found many supporters is that of Langmuir. Based on numerous experiments on gases with tungsten wire in high vacua and also with platinum and palladium, Langmuir concludes that the metal surface is capable of holding a film of substance one molecule thick to which it adheres more or less firmly. Reaction may then take place ( I ) between molecules or atoms adsorbed in adjacent spaces, ( 2 ) between the adsorbed films and the underlying solid, and (3) between the adsorbed film and the colliding gas molecules. Thus the interaction of oxygen and hydrogen in presence of platinum is attributed to the adjacent adsorbed atoms, whilst between carbon monoxide and oxygen it is between oxygen atoms and the colliding carbon monoxide molecules. If the film under the conditions of the experiment is not readily removed from the metal surface the reaction stops. The film acts as a catalyst poison,” p. 180. “With palladium and hydrogen ethylidene malonic ester gives ethyl malonic ester; but with sodium amalgam effects a union of the molecules by linking up the p carbon atoms,” p. 183. ‘Condensation may then be defined as the union of two or more organic molecules or parts of the same molecule (with or without elimination of component elements) in which the new combination is effected between carbon atoms,” p. 195. “The work of Zincke and Hantzsch on the action of chlorine in akaline solution on the phenols and other aromatic compounds has afforded numerous examples of the change of a 6-carbon ring into a 5-carbon ring. We may take the case of ordinary phenol which passes into a derivative of cyclopentane. Most of the other phenols behave in a similar fashion. Wreden found that when benzene is reduced with hydriodic acid a t 300”, it yields a hydrocarbon C6H12,which was a t first mistaken for cyclohexane; but its low boiling-point (70’) and its conversion into a mixture of glutaric, succinic, and acetic acids on oxidation left no doubt as to its identity with methylcyclopentane. Zelinsky also found that cyclohexanol, on reduction with hydriodic acid, gives a mixture of cyclohexane and methylcyclopentane. Aschan has since shown that cyclohexane changes to methylcyclopentane on simply heating in a closed tube with or without aluminium chloride,” p. 209. The activity concept is apparently working its insidious way into organic chemistry, p. 320. “More recently the question of the significance which should be attached to the term ‘active mass’ has been much discussed. I n the case of gaseous reactions a t moderately

1436

NEW BOOKS

low pressures, the volume concentration would seem to afford a satisfactory measure of this quantity. The matter is much less simple when the reacting substances are present in large concentrations in a liquid medium. I n such cases the active mass is, in all probability, more appropriately measured by the ‘activity’ or thermodynamic concentration, the value of which may be obtained from measurements of vapour pressure or from osmotic data, and in the c u e of ionized reactants from measurements of potential difference.” I t was rather interesting to read, p. 378, that “althoughempiricalinorigin, the Arrhenius formula has been given a theoretical basis in terms of the so-called radiation’ theory of chemical change.”

“It must be confessed that we are still profoundly ignorant of the change which substituents effect in the character of the molecule as a whole, the causes which determine the rules of orientation, the reason why positive groups like methyl and amino groups facilitate nitration, sulphonation, acetylation by the Friedel-Crafts method, etc., why negative groups assist hydrolysis of cyanides, reduction of nitro groups, acetal formations, etc., and a host of other phenomena of a similar nature. Until clearer views obtain on these subjects i t can scarcely he hoped that real progress will be made on the nature of chemical change. The expression ‘steric hindrance’ meantime affords a useful if not a very appropriate title for docketing a number of allied phenomena,” p. 41 I . The second volume deals with structure and the chapters are entitled: physical properties and structure; colour and structure; isomerism and stereoisomerism; stereochemistry of unsaturated and cyclic compounds; stereochemistry of nitrogen; isomeric change; the benzene theory. “Violuric acid and its dimethyl and diphenyl derivatives, together with some of their esters, are colourless or faintly coloured, but yield brightly-coloured salts. iiot only do different metals and organic bases produce differently coloured salts; but the same metal yields differently coloured salts and solutions according to the solvent employed. The phenomenon of one salt existing in differently coloured varieties is termed by Hantasch pantochromism. Potassium, rubidium, and caesium diphenyl violurate can each exist in blue and red modifications, and lithium diphenyl violurate gives both red and yellow salts,” p, I 18. The author trusts Ostwald and not his own knowledge of organic chemistry, when he says, p. 137, that “methyl orange, on the other hand, is a moderately strong acid whose ion is yellow, whereas the non-ionised molecule is red.” Actually, methyl orange as an indicator is a weak base. After giving Ostwald’s theory of indicators, the author says, p. 138, that “the other theory of indicators is a chemical one.” I t is not another theory. I t is a modification necessary in certain cases hut not in all. According to Heivitt “fluorescence is conditioned by a process of oscillatory tautomerism, or rapid vibration between tautomeric forms, of a peculiar kind, found among a certain class of substances capable of exhibiting what has been termed double sgmme2rical tautomerism. The two modifications absorb and emit alternately light rays of a different period,” p. 148. The reviewer is sceptical as to Plotnikow’s second law, p. 152. “The second law states that photochemical action is proportional to the amount of light absorbed and is independent of the wave-length.” “The amount of light energy utilised by the leaf has been measured by Pfeffer by estimating the amount of starch produced in I sq. em. of leaf surface per second of exposure and comparing the heat of combusion of the starch with the calorific effect of radiation on the same surface. According to his results only 0.6 per cent. of the total energy was absorbed, but, as the method is affected by certain serious errors, no great reliance can be placed upon the result, A very different result was obtained by H. T . Brown, who, in place of measuring the total solar energy falling on the leaf, estimated only that which was absorbed by the chlorophyll and was consequently photochemically and otherwise active. The amount of solar radiation taken up by the leaf was determined by means of a Callendar

NEW BOOKS

I437

radiometer before and after transmission through the leaf. The energy thus absorbed was found to vary in different leaves between 64 and 77 per cent.,” p. 168. “Racemisation is usually effected by rise of temperature. It was first observed by Pasteur, who obtained both racemic and mesotartaric acid by heating cinchonine d-tartrate to 170”. Jungfleisch modified and improved the method, heating tartaric acid with I O to 1 5 per cent. of water in sealed tubes to 1 7 j o for several hours, and obtained considerable quantities of racemic and mesotartaric acid. The same process has been found to bring about the racemisation of aspartic, mandelic, isopropylphenylglycollic, and camphoric acid. .Ictive pinene, limonene and phellandrene, active amyl alcohol, and many of its derivatives are rendered inactive by heating. Active lactic acid is converted a t 150’ into inactive lactide, and active quinic acid into inactive quinide,” p. 200. “Tl-hen studying the action of reagents on the active chlorosuccinic acids, Kalden found that by replacing chlorine by hydroxyl in the laevo compound using a strong base (potassium hydroxide or ammonia), d-malic acid is formed, but if silver oxide or water is employed the l-acid is obtained. The same thing occurs if the dextro-chlorosuccinic acid is used, that is to say, potassium gives a malic acid of opposite sign and silver oxide one of the same sign. \Talden has studied the action of a variety of metallic oxides in the same way, and has shown that they form a series, the end members of which produce diametrically opposite effects in the character and amount of rotation, whilst the intermediate members form products which in sign and value lie between the two extremes. The hydroxides of the strong bases, rubidium, potassium, ammonium, copper, cadmium, barium, lead, and sodium, cause inversion of sign in different degrees, whereas those of silver, thallium, and mercury produce a malic acid having the same sign as the original malic acid,” p. 206. “.hother chemical method, devised by K. H. Meyer, depends upon the rapid union of the enolic, but not of the ketonic, form with bromine. The former is unstable, and is a t once decomposed with the separation of hydrogen bromide and the formation of the bromoketone. On adding potassium iodide the bromoketone is reduced, and the iodine set free is estimated by titration in the usual way. The amount of the free iodine gives that of the enol form present. A standard solution of bromine in alcohol is introduced in excess and pnaphthol immediately added in order to remove the uncombined halogen. On the addition of potassium iodide, iodine is liberated and estimated as described above,” p. 373. “Laar’s tautomerism or oscillating structures, and Baeyer’s pseudomerism or single, stable structures, are limiting cases of allelotropism or equilibrium mixtures of isomers. The theory which has been recently developed by T. XI. Lowry has been moulded on a still broader basis. In place of the word tautomerism and the various other names applied by different observers to indicate different views of the same phenomenon, he has introduced the single expression dynamic isomerism, which he defines as reoersible isomeric change,” p. 388. “At an early period in the history of the benzene formula, Kekuli. put forward a dynamic hypothesis to explain the equivalence of the two ortho positions. This was followed by I h o r r ’ s oscillation formula, in which only the hydrogen atom was assumed to oscillate between each pair of carbon atoms. Knorr’s view, which bears a close resemblance to Laar’s theory of tautomerism, was the direct consequence of the observation establishing the identity of methyl pyrazole obtained from two different phenylmethyl pyrazoles, and has already been discussed. In 1897 a new dynamic formula was proposed by Collie, in which the carbon groups as a whole are supposed to rotate as well as change their relative positions. T.7;ithout a model it is impossible to describe the evolutions of this mobile system; but it is claimed that it represents in turn the Kekule and centric arrangement as phases of the one formula. Latterly, the study of the absorption bands in the ultra-violet region of the spectrum has led to views on the dynamical condition of benzene, which promise a very interesting development. According to Hartley, six, or according to Baly and Collie, seven, distinct absorption bands are produced by benzene. These bands are accounted for by synchronous oscillations of the molecule, in much the same way as a tuning-fork vibrates

1438

KEW BOOKS

in response to a note of definite pitch. The nature of these molecular vibrations are, however, differently interpreted by the two observers. Hartley supposes the carbons to be rotating and alternately passing through a double and single (or centric) link phase. If the passage from single to double linking produces a band, the first phase which involves the making of three double links will produce three bands and the second phase another three bands, making six altogether, though it is not obvious why the same recurrent process should produce six sets of oscillation frequencies. Baly and Collie take a different view. The oscillations are connected with dynamic change involved in the making and breaking of the links between one or more pairs of carbon atoms,” p. 465, The third volume is devoted to synthesis, the special chapters being headed: the carbohydrates; fermentation and enzyme action; the purine group; the proteins; the terpenes and camphors; the alkaloids. “The abnormal behavior of fructose in reducing alkaline metallic salts, which is usually regarded as characteristic of aldehydes, is ascribed to the ready oxidisability of hydroxyketones. The case is similar to that of the hydroxy-acids, which like tartaric acid are easily oxidised and separate silver from ammonia-silver nitrate, whilst simple dibasic acids like succinic acid have no such action,” p. 4. “The conversion of one monosaccharide into another has been effected in the follon-ing way. Fischer found that on heating the monobasic acids (derived from the sugars by oxidation) in aqueous solution with pyridine to a temperature of 1 3 0 ~ - 1 5 0a” molecular change occurs. The hydrogen atom and hydroxy1 group attached to the carbon atom next to the carboxyl group are interchanged and a new stereoisomeric modification is produced. It occasionally happens that the conversion is complete; but, as the process is reversible, the original and the newly formed product are as a rule present as an equilibrium mixture,” p. 9. “Lobry de Bruyn and van Ekenstein found that under the influence of alkalis, alkaline earths, sodium acetate, lead oxide, guanidine, etc., the hexoses are transformed slowly into mixtures of their isomers. Each of the hexoses, glucose, fructose, and mannose, forms under these conditions a certain proportion of the other two, together with certain other sugars, e.g. glutose, a y-ketose, which is also found in molasses,” p. 13. “If it were possible to prepare glycollic aldehyde in quantity and build up the sugars in successive stages from it, by means of the cyanhydrin reaction, all of the stereoisomers would probably be obtained and their configuration could be determined without difficulty,” P. 24. “The discovery of the ferments concerned in gastric digestion must really be ascribed to Reaumur (1752) and the Abbe Spallaneani (1785). The latter caused birds of prey to swallow small sponges attached t o a string. After withdrawal, the sponges yielded a small quantity of gastric juice which was able to dissolve and change fragments of meat. These results were, however, not accepted as correct until many years later,” p. 89. The X-ray examination of cellulose indicates unit cells containing four C e H d h groups, p. 77, The author thinks that it is probable that haemoglobin, unlike most other proteins, forms a true solution in water, p . 155. Sodium removes an atom of hydrogen from pyridine, and dipyridyl is formed by the linking of two molecules, p. 308. “How is the term alkaloid to be defined? Koenigs suggested that the name, which was originally applied to all vegetable bases, including caffeine, theobromine, betalne, choline, etc., should be restricted to those vegetable products which are derivatives of pyridine only. This would exclude caffeine and theobromine, which do not differ very widely from the alkaloidal bases. In the present state of the subject an exact definition is not easy to frame, and possibly, as our knowledge grows, the line of demarcation between the alkaloids at present known and other vegetable products may become gradually obliterated. For the present, however, an alkaloid may be defined as a vegetable base which contains a cyclic nitrogenous nucleus,” p. 306. This is a remarkably interesting book. The reviewer has enjoyed immensely the reading of it. He recommends it most highly to all chemists and with especial emphasis to physical chemists. This is the kind of book they have been looking for. Wilder D. Bancroft

NEW BOOKS

I439

The Romance of the Atom. B y Benjamin Harrow.. 20 X 13 cm; p p . 162. New York: Boni and Liveright, 1927. Price: %l..50. The introductory chapters are entitled: alchemy and the d a m of chemistry; Priestley and the dawn of modern chemistry. Then follow nine chapters on the atom entitled: the atom; MendelBeff; Crookes; Madame Curie; the energy of the future; the structure of the atom; the work of Rayleigh and Ramsay; the work of Langmuir. After this come three chapters on science and life, with the sub-heads: the origin of life; the application of science; the scientist as citizen. In the preface the author says that “an attempt is here made to describe in non-technical language, but with strict regard for accuracy, the glorious achievements of chemists and . physicists in unravelling some of the profound mysteries hidden within the atom. If the magnificent work of Bohr receives but scant mention, it is because, in the first place, my primary object in writing the book was to explain, in a simple way, just what chemical action is; and this Langmuir’s theory does admirably; further, to comprehend Bohr’s theory requires a knowledge of physics and mathematics much beyond the grasp of the average reader. To ‘popularize’ Bohr’s theory is not unlike the attempt to ‘popularize’ Einstein’s theory: it cannot be done.” Wilder D. Bancrojt

. .

Lehrbuch der Thermochemie und Thennodynamik. B y 0. Sackur. Second edition by C1. 1’. Simson. 2.5 X 20 cm; p p . mi 347. Berlin: Julius Springer, 1928. Price: 19.40 marks. The first edition of Sackur’s Thermodynamics has been well known in its English translation for some years, and there is no doubt that it was one of the most clearly written works on the subject available. Since its appearance there have been many advances both in the theory and in the experimental results. These have to some extent been incorporated in the new edition. I t may be remarked that the useful abbreviations cal. and k.caZ. for gram calorie and kilogram calorie have been adopted. The section on calorimetry is too brief to be really useful: Joly’s method is mentioned without criticism and nothing is said of the new methods developed by T. W. Richards and his school. I n the consideration of the experimental determination of the specific heats of gases practically all recent work, except a little carried out in Germany, is omitted, and this section is quite out of date. “Bringworth” on p. 74 should be Brinkworth. The treatment of van der Waals’ equation is purely algebraical and the really difficult question of units is ignored, as it too frequently is in textbooks. The introduction of the kinetic theory of gases in the section on the thermo-dynamics of gases is perhaps likely to be confusing and Joule’s equation (aulas), = 0, however “strange” it may seem to the beginner, is a safer basis than the kinetic formulae, which are quite foreign to the spirit of thermodynamics. The quantum theory is introduced early but no deductions of the formulae are given. The deviations from the Debye T3-law observed by Onnes and his school should have been mentioned here, and not deferred to p. 321. The section on the energy of solids is otherwise excellent, although the scanty reference to lattice energy on p. 93 could have been extended with advantage, since this part of the subject is now rather prominent and is certainly interesting and capable of frequent application. The quality of any book on thermodynamics may be estimated by its treatment of reversibility, and here the present volume is entirely satisfactory, the treatment being based on that of Planck. The inequalities for irreversible processes, however, are introduced in the usual way, yet it is questionable whether they really follow from the two laws of thermodynamics. They do, however, emerge almost automatically from the treatment of irreversibility adopted. The applications of the two laws follow in a satisfactory way and only a few points call for comment. The rather detailed account of the applications of the B a s e Rule is rather tedious and out of place, but the careful treatment of Le Chatelier’s theorem is

+

I440

NEW BOOKS

unusual and commendable. The interpretation of the differential coefficient i., the maximum work equation (4) on p. 147 is not compatible with the suffix i’ in the equation itself. “Activity” appears very briefly on p. 246 but no use is made of the conception. The list of values of the normal electrode potential on p. 272 is out of date and Kruger and Krummreich’s very important work on absolute potentials should have been mentioned. The treatment of chemical constants and their relation to statistical mechanics is good but rather brief, and no statistical equations are actually deduced, although the relation between probability and entropy is explained in some detail. As an indication of the unusually careful treatment of the whole subject, two examples may be mentioned. The discussion of solution pressure on p. 271 makes it clear that it is not the concentration of ions i n the metal which is concerned-a statement which almost uniformly appears or is implied in the usual textbooks when any explanation is attempted; and in the deduction of the maximum work of a gas reaction on p. 324 the external work term, ZnlRT, duly appears, as it should but rarely does. Y o doubt this new edition of Sackur will be translated and so made more easily available to English and American students. If this is done some of the omissions mentioned might usefully be made good, the International Critical Tables turned to account and the literature references extended so as to cover more of the recent English and American work than seems to have been available to Dr. Simson, who has otherwise done her work extremely well. The book is one which can be read with profit by all students of chemistry. J . R. Partington. Laboratory Glass Blowing. B y F . C . Frary, C. S . T n y l o r . and J . D. Edwards. 21 X 16 cm; p p . wiii 116. ATew Y o r k : McGraw-Hill Book Co., 2928. Price: S1.50. This book was first published in 1914 as “Laboratory Manual of Glass Blowing” and has now been altered and supplemented particularly in reference to Pyrex glass which has come into such wide use since that time. The purpose of the book is stated, “to provide a clear and detailed discussion of the elements of glass working.” These elements are wisely held to include those operations which the scientific worker may be called on to perform in the manufacture and repair of simple glass apparatus. The chapters are entitled: glass and its working characteristics; general operations; elementary exercises; advanced exercises; modified methods and special operations; glassto-metal seals and joints. Under these headings are discussed such subjects as: devitrification; annealing; types of glass and their properties; the arrangement of equipment; cleaning and cutting glass; operations on tubes; capillary tubing; joints and repairs on apparatus; ground joints; vacuum tubes; sealing glass to Pyrex, porcelain, platinum, and base metals. The appendix gives formulas and directions for use of; platinizing solutions, stop-cock lubricants, vacuum wax, deKhotinsky cement, cement. The book is well written and succeeds in imparting a great deal of information. The operations are arranged in just about the same order as that followed by expert glass workers in their instruction to apprentices and the descriptions of these operations are detailed enough for ease in carrying them out. In addition, many of the procedures are well illustrated by drawings showing each step. It is anticipated that this little book will be welcomed as a valuable aid by that army of laboratory workers who have some skill and much ambition to do things with glass. HerbeTt L. Dacis.

+