RECENT BnOKS ELECTR~NIC INTERPRETATIONS OX ORGANIC CBEMISTRY. A. E. Remick. Assistant Professor of Chemistry, Wayne University. John Wiley & Sons. Inc., New York, 1943. v 474 pp. 19 figs. 77 tables. 13.5 X 21 cm. $4.50. The title of thij book is scarcely a n accurate description of its scope nnd content. A few sentences lifted from thr nuthor'iprcface may be more informative. " . A rati5factory preparative pruccdwe demands: (1) that the proposed reaction be thcrmdynamically powihlc. (2) that the renction tdsc dace with asullicitntl~hkh vdocitv to be ~ r a c t i cable, and ( 3 j that there be as few sidereactions possib;le and that those which are inevitable take lace much mare slowlv than ~, thc mnin reaction. It sholnld be a t once apparent that if we would predict these things we mu\t first undersrmd the effccts of atructurd and environmental changes on both the free energies and activation energies of organic reactions. This seems to be a demand for a fusion of electronic theories of organic chemistry with such modem developments in physical chemistry as the quantummechanical concept of resonance and the transition-state theory of reaction rates. The main purpose of this hook is to show how this fusion of ideas has been satisfactorily achieved. I t is intended that this book shall serve the dual purpose of a review and an advanced textbook.. . ." In your reviewer's opinion the author has made, on the whole, an intelligent choice of subject matter, when judged on the basis of the objectives announced. Some readers may feel, with the reviewer, that a disproportionate amount of space has been expended on the rather nebulous physical concepts, esoteric terminology, and tortuous interpretations of the English school-now chiefly of historical interest to American organic chemists, a t least. This, however, is perhaps a matter of personal taste and opinion. Within the areas selected for treatment the coverage of significant literature has been reasonably thorough, although there are a few rather surprising omissions, such, for instance, as the neglect of Anderson's study [I. Ckem. Soc., 57, 1673 (1935)], indicating that the basis of the conductivity of hexaphenylethane in polar solvents like liquid sulfur dioxide is ionization in the sense (C.H&C 5 (CsHs)sC+ s, rather than in the sense (CsH&C: C(CsHs)~ (C6H5)&!+ 4- (CsHs)C-, as Gomberg had earlier supposed (p. 46). The text is considerably better mitten than the average, and the exposition is exceptionally lucid, being marred chiefly by occasional lapses into oversimplification or by condensation to the point of mild misrepresentation. Cf., e. g., the beginning sentence of the first new paragraph onp. 140: "Thereisconsiderable evidence from the field of quantum mechanics which shows that the energy of a bond between two given atoms is not much affected by other atoms in the molecule." I n the field of critical evaluation and independent interpretation and synthesis the author lays himself open to criticism only for the modesty with which he consistently refrains from attempting anything of the sort. In the admittedly difficult task of arrangement and organization of subject matter the author has permitted his projected outline to result in some rather gruesome dismemberments of topics that, in thereviewer's opinion, should have been highly integrated a t all costs. By way of example, a section entitled "Bond Energies" occupies the greater part of pages 1 3 M 3 in Chapter VI ("Some Contributions from the Field of Chemical Physics." pp. 133-87). The opening discussion would lead the student to believe that "bond energies" may be expressed in terms of AH values. T w Little emphasis is laid on the fact that Pauling's socalled "bond-energy values," reproduced on page 141, include kittens of such radically different breeds as H-H and 1-1 on the one hand and C-H and C-C on the other. The former may be expressed in terms approximating pure potential energy values;
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for the latter this was not even attempted. On page 142 Kistiakowsky's data on the heats of hydrogenation and bromination are cited as indicating that there may, after all, he something a trifle smelly about t h e postulate of "constant hond-energy values," although nothing is said of the even more cogent argument to this effect supplied by Rossini's heats of combustion and derived energies of formation for hydrocarbons. The subject of bond energies craps up again, pages 290300, in Chapter I X ("Electron-Pairing Reactions," pp. 259-310). On page 295 Baughan's very proper criticism of Pauling's adopted value for the vaporization of carbon, and the effect of more probable values of this quantity an Pauling's C-H and C-C "boud-energy" values are mentioned. On page 297, in a footnote, the student is reminded of the distinction between AH and AF, and the practice of using AH values to implement AF arguments is criticized. At length, on page 300 some physicochemical evidence to the effect that primary, secondary, and tertiary C-H bonds differ appreciably in strength is adduced, but spectroscopic evidence (cf. Brackett, Barchewitz) and quantum-mechanical calculations (cf. Eyring) leading to the same conclusion are ignored. Nowhere isit pointed out that arelatively small difference in the values ascribed to methane and primary C-H bond energies would lead to the necessity for a relatively large upward revision in the value ascribed to an ethane C-C bond on the assumption that all C-H bonds are equivalent. The appendices ("I,An Elementary Exposition of the Theory of Atomic and Molecular Structure," pp 42333; 'TI, Refractivity and Chemical Constitution," pp. 43444; "111, Dipole Moments," pp. 445-8; "IV, Background for the Study of Nonaqueous Solutions," pp. 449-60; "V. Table of Basic Principles," pp. 4614; T I , Table of Symbols," pp. 4 6 M ) should prove useful, especially t o the student handicapped by limited physicochemical training. Your reviewer now fears that in the attempt t o document his criticisms specifically he may have transmitted a less favorable impression than he, himself, holds of the volume under consideration. Frankly, your reviewer is your reviewer's favorite author, and he can find so much to criticize in his own work that he never gets around to offeringit for publication. OTTO R E r m n U N N B R ~ I T YOB CHICAGO
ILLINOIS CEUCAOO.
BI~CHEMISTRY FOR MEDICAL STUDENTS.William Veale Thorpe, Reader in Chemical Physiology, University of Birmingham (England). Third Edition. The Williams & Wilkins Company. Baltimore, 1943. viii 476 pp. 39 figs. 14.5 X 21 cm. $4.50. Restrictions in the use of paper are said to have governed the size of this little book, but they have not "cramped its style" or usefulness, for here we have a beautifully compressed, fairly brief, fully modern presentation of the subject of normal human biochemistry. The preface to the volume gives a lucid and honest evaluation of it. "The aim of this book is to present an account of the biochemical Drocesses known to occur in the healthv human h d y ~.upl,lrnlentin):ntin rcrorntnrndcd tat-books of Phyiiology)." In thi. third rclicion "a ron&leral~lrnrnoont uf new material has, hmvwer. bccn irlcorporaterl by rrarrangnnmt of the text. In response to frequent requests a short chapter on the Chemistry of Respiration has been added." The author has "tried to provide what the medical or dental student may want to know and to omit that which he is never likely to require." A few of the features found helpful here are the thorough treatment of physicochemical principles involved in the behavior of water in tissues, the large and clear structural formulas, the use of
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