Orgo Cards: Organic Chemistry Review (Wang, Steven Q.; Razani

Sep 9, 2003 - of a student who saw this product on my desk. Written by an organic professor with 35 years of experience and four medical students, thi...
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Chemical Education Today

Book & Media Reviews

Orgo Cards: Organic Chemistry Review by Steven Q. Wang, Babak Razani, Edward J. K. Lee, Jennifer Wu, and William Berkowitz Barron’s Educational Series: Hong Kong, 2002. 160 cards, ISBN 0764175033, $18.95 reviewed by Eugene Gooch

“Wow, there’s a lot of them!” This was the first reaction of a student who saw this product on my desk. Written by an organic professor with 35 years of experience and four medical students, this set of review cards is offered to ease the burden of students who take organic chemistry. The authors comment, “…studying and memorizing this large body of information could pose a serious challenge to college students who have a limited amount of study time. The solution to this problem, therefore, lies in distinguishing important material from trivial facts.” Their advice to students is to use the cards “for preview and review,” and “Endeavor to understand the reaction ‘Mechanisms’ rather than just blindly memorizing the reactions.” There are 19 sections on various classes of compounds. The outline of each section is unexceptional: a short topic list, general information on structure, physical and chemical properties, nomenclature and spectroscopic properties (IR, NMR, and CMR data), then methods of synthesis, and characteristic reactions. Two additional sections are dedicated to carbonyl α-substitution and condensations. There is a card with pKa values for various functional groups. Two cards include molar mass, pK, and pI values for the common amino acids. There is a significant effort to cross reference details that appear in different sections, and there are five index cards at the end of the set. The major strength of this product lies in coverage of the reaction mechanisms. Successful organic students will follow the advice mentioned above, with which I wholeheartedly agree. It is apparent that the authors focused their attention most closely on doing an outstanding job here. Mechanisms are written out using curved arrow notation, steps are numbered, and a sentence describes the details of each step. Efforts are made to describe both ionic and radical mechanisms accurately. Stereochemical details are integrated into the descriptions of reactions and their mechanisms. The authors seem to have gone to great trouble to provide a complete repertoire of reactions. They even include the synthesis of sulfides in the ethers section and the Wohl (not Ruff ?) degradation of carbohydrates. If the authors had focused exclusively on cards with organic reaction mechanisms, they would have made a unique product that is one of the best I have seen in a long time. However, the devil is in the details, and the product is marred by a number of shortcomings. One must wonder at the

edited by

Jeffrey Kovac University of Tennessee Knoxville, TN 37996-1600

“trivial facts” selected for omission by the authors: concepts of sigma and pi bonding, resonance, and aromaticity; Brønsted or Lewis acid–base concepts; basic stereochemical definitions and relationships. Zaitsev’s rule and the antiperiplanar stereochemistry of elimination are covered in the reactions of alkyl halides, but there is no cross reference to these concepts in the synthesis of alkenes section. Carbocation rearrangements are not mentioned in the alkyl halides or alkenes sections, nor are they in the index; one finally encounters them with the Friedel–Crafts alkylation of benzenes. Conjugate additions to α,β-unsaturated aldehydes/ketones are included, but 1,2 versus 1,4 additions to dienes are omitted. The base-catalyzed halogenation of ketones does not include the final cleavage steps of the well-known haloform reaction. Synthesis of peptides is covered well, but only perfunctory mention is made of Merrifield’s method. Further, the cards are replete with trivial mistakes that become progressively more distracting. A typographical error on a carbinolamine produces an amusing “divalent hydrogen” with a lone pair. One finds that an amide IR band occurs at a frequency of 16,600 cm-1. There is an alkyne structure with a C=C bond and another with a dative bond. The careless proofreading of this product is persistently underscored by two pentavalent carbons on the synthesis map and more scattered about on the other cards. One also discovers several exotic reagents: NH2NH2KOH, LiAlH(O+tBu)3, H2/NI, and OH radical. The 5 1/2 in. ⫻ 7 in. cards seem quite durable. They are printed on heavy stock and have rounded corners. However, the text is nine-point type, and the structures, reactions, and mechanisms are in seven- or eight-point type. (Maybe that’s why all those errors weren’t caught.) The student who examined these cards complained about the small size of the type, and unlike me, she is young and does not wear bifocals! There are two attempts to “ultra-condense” this summary of organic chemistry. In addition to the spectroscopic data mentioned earlier, on one card there is a set of “typical spectroscopic values” for IR frequencies and NMR/CMR chemical shifts. The accompanying footnote says it all, “A single value is given for most of the functional groups, but wide ranges are common”. For the thoughtful, intelligent interpretation of spectra, these single values are virtually useless. (I can envision a number of sophomores who would see a CMR signal at 65 ppm and deny they had the spectrum of an alcohol since it didn’t match the card’s value of 60 ppm.) Next, to illustrate the many methods for functional group interconversion, the authors add a “synthetic map” card with 47 reactions that I presume were deemed most essential to learn. To picture the map, imagine an intermediary metabolism chart printed in seven- and even six-point(!) type on a 4 in. ⫻ 4 1/2 in. envelope. Most students are intimidated by the reputation of organic chemistry, while others see the course as nonessential to their career goals. While they usually have the ability to

JChemEd.chem.wisc.edu • Vol. 80 No. 9 September 2003 • Journal of Chemical Education

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Chemical Education Today

Book & Media Reviews meet the challenge and succeed, many seek any mechanism by which they can pass the course with minimal study time. Products like Orgo Cards pander to such desires and will not be of benefit to the student with mediocre talent or poor motivation. The best students who buy this set may be bright enough to focus on those very well done mechanisms. But

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remember, there’s nothing in Orgo Cards that isn’t already in a good organic text. Eugene Gooch is in the Chemistry Department, Elon University, 2625 Campus Box, Elon, NC 27244; [email protected]

Journal of Chemical Education • Vol. 80 No. 9 September 2003 • JChemEd.chem.wisc.edu