Textbook of organic chemistry (Gero, Alexander)

2i4 the failure of most ketones to form bisulfite addition compounds is ... Oregon Slate University. Corvallis. Semimicro Experiments in Chemistry. Jo...
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BOOK REVIEWS (Continued from page AP.91) fields of thermodynamics or electrochemistry. ERNESTYEAGER Western Reserve Vniowsity Cleveland, Ohio Textbook of Organic Chemistry

Alezander Gero, Hahnemann Medical College, Philadelphia. John Wiley and 679 Sons, Inc., New Yark, 1963. ix pp. Figs. and tables. 17.5 X 24.5 cm.

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mechanisms in the elementary organic chemistry course, 8. trend with which this reviewer is wholeheartedly in favor. At least two excellent teats stressing this approach-Cram and Hammond, and Morrison and Bovd-have alreadv an-

attempts a modern approach to organic chemistry, comes off rather poorly indeed. I n fact much of its presentation of "mechanisms" will give a. physical-organic chemist pause. First oi all, except for isolated spots, the book generally ignores the most basic premise of all mechanistic eonsiderations relative to the effect of structure on rertctivity, namely, that the rats of an organic reaction is determined by the energy (or more accurately, free energy) difference between reactants and transition state. Instead it chooses to attempt to explain structure-rate effects almost entirely on the basis of differences in ground state energies of reactants, a procedure which is theoretically incorrect, and despite the fact it often leads fortuitously to correct predictions, is pedagogically indefensible, particularly in the elementary course, which represents the critical formative period of a student's basic approach to organic chemistry. Second, the following peculiar statement relative t o the canonical forms of a resonance hybrid occurs on p. 64: "The course of its [a compound's1 reactions, however, may be determined more by the higherenergy canonical structures because the principal structure with its lower energy is less likely to be responsible for change than the more unstable, higher-energy cananie d structures." This extremely questionable statement then proceeds to attain the status of a first principle and is employed repeatedly in the remainder df the book, as the supposed mechanistic explanation for various phenomena.. Some typical examples of the types of errors that occur throughout the book and that detract seriously from its treatment of reaction mechanisms are: On p. 81 in discussing the acidity of eyclopentadiene the statement is made that the eyelopentadienyl anion is more stable than cyelapentadiene. If this were literally true cyclopentadiene would have a. K, greater than unity, which, of course is not true. On p. 106 there occufs an ohvioudy incor(Continued m page A825) Volume 40, Number 10, October 1963

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BOOK REVIEWS reet explanation of the mechanism of the disproportionation of alkylbenzenes. On p. 191 i t is strongly implied that tertiary alkyl halides do not undergo E2 elimination when in actual fact theso halides undergo such rliminat,ions much more readily t,han secondary or primary halides. On p. 20i in see. 7.12 and p. 275 in sec. 10.20 occur two of the many ( a t lmst 20) examples of the application of the unusual postulate, r r f e r r d t o earlier, about renetions involving the most unstable canonical forms of n resonance hybrid. On p. 2i4 the failure of most ketones t o form bisulfite addition compounds is ascribed t o n rate phenomonon rather than t o the fact the over-all equilibrium is unfavorable. A further general criticism of the book's treatment of mechanism is t h a t i t gives much too little emphaais to the very considerable role which strric effectsplay in a wide range of organic reactions. It i s a p i t y that the treatmentof reaction mechanisms comes off so poorly, for the treatment of descriptive organic rhemistry is generally good, and the baok as a rholo is quite readably written. I t also has the feature of providing unusually detailed coverage of heteroeycks, and quite rxtensive coverage of other binlogically or pharmaceuticrtlly important compounds. Treatment of stereochemistry varies from excellent in the chapter dcaling with ring strain and geometrical isomerism (Chap. 4) t o acceptable in t h a t (Chap. 9 ) dealing with optical isomerism. However, because of the shortcomings oi the book's treatment of mechanisms and because this material iis so extensive, and so interwoven with the rest of the text that i t cannot be overlooked or omitted, this reviewer regretfully cannot recommend adoption of Gero's baok as an elementary organic text.

JOHNL. KICE Oregon Slate University Corvallis Semimicro Experiments in Chemistry

John W. Sulcoski, Dallas Senior High School, Dallas, Pennsylvania. Burgess Publishing Co., Minneapolis, lOfi3. viii 128 pp. Figs. and tables. 21.5 X 27.5 cm. Paperbound. 52.90.

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"Semimicro Experiments in Chemistry" has been written for those chemistry instructors who like the coneopt t h a t rxperiments in the student manual should contain no fill-in blanks, but rather should require an essay-typo student report. The general format for this report is included in the teacher's manual and, if iallowed, should ease the problem of grading and improve the laborstory instruction. There are 51 experiments in the manual, more than half of which are quantitative in scope, requiring measurement., graphing, and interpretation of data. The experiments follow the "open-ended" idea pioneered by the Manufacturing Chemists Association. The directions are brief but sufficient. Questions are posed for good (Continued on page A827) Volume

40, Number 10, October 1963

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