Organic Chemistry at a Glance (L. M. Harwood, J. E. McKendrick, and

Jun 1, 2005 - Organic Chemistry at a Glance is designed for people who have only enough time to glance at a book—literally. The authors' goal was to...
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Chemical Education Today

Book & Media Reviews

Organic Chemistry at a Glance by L. M. Harwood, J. E. McKendrick, and R. C. Whitehead Blackwell Publishing, Oxford, UK, 2004. 103 pp. ISBN 0865427828 (paper) $24.95 reviewed by Eugene Gooch

Good things come in small packages. Organic Chemistry at a Glance is designed for people who have only enough time to glance at a book—literally. The authors’ goal was to create an effective memory aid for those who wish to review organic chemistry. They have distilled concepts of structure, bonding, stereochemistry, and reaction types into a mere 41 pages. The text itself appears on every odd-numbered page and is complemented by line diagrams on the facing, evennumbered page. The result is six chapters and less than one hundred pages of the most concentrated “essence” of organic chemistry that I have ever seen. In one sense, the book’s organization is similar to that of a Web site. Parenthetic cross-references function as Web links. For example, when reading about the E2 mechanism, the reader can navigate quickly to a concise summary of the anti-periplanar relationship in the stereochemistry section two chapters back. These links are plentiful in some chapters, although scarce in others. George Bernard Shaw said, “England and America are two countries separated by a common language.” Despite this, it’s a good idea to glance at a book authored by our colleagues on the other side of the Atlantic. Consider their statement of Hückel’s Rule: “To exhibit aromatic stabilization, a molecule must possess a cyclic, planar, overlapping array of porbitals containing a total of (4n ⫹ 2) pi electrons (where n is any integer).” What a marvelous, concise gem of linguistic precision! The authors are obviously passionate about both accuracy and using language that is complete as well as technically correct. Because of this, a definition occasionally sounds cumbersome: “A sigma bond is formed by linear overlap of two atomic orbitals which results in a region of high electron density of circular cross-section concentrated between the two participating nuclei.” Can you visualize it without referring to a diagram? The diagram on the facing page removes all ambiguity and allows the reader to move on, yet many U.S. students should stop to appreciate the effort it takes to state something so accurately. One can relish some of the contrasts between British and American English. What is known as “minor resonance contributors” in the U.S. is called “extreme resonance canonical forms” by the British. The whimsical terms “stemane, stemene, stemyne, stemol, and stemoic acid” comprise an elegant approach to reviewing basic nomenclature. It’s inter-

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esting to speculate on what U.S. English will sound like as our language evolves over another 800 years…. Illustrations seem to be quite well done. The lack of mistakes here is so evident that I am half-convinced the authors (while discussing homolysis versus heterolysis) intentionally drew the iodine molecule as I⫼I instead of I:I or I⫺I. A fine job has been done on the mechanisms. However, lone pairs are not explicitly shown in all species, so electron pairs sometimes seem to “disappear” when bonds are cleaved or formed. Virtually no U.S. textbooks mention that there are four major conformations of cycloheptane and 11 for cyclooctane. No functional group list is given except for a “priority in nomenclature” list on p 14. Less common functional groups like amine oxide, peroxy, diazo, thioacetal, sulfoxide, and selenoxide are mentioned without explanation later in the book. The treatment of carbonyl additions from cyanohydrins through condensations is solid, following traditional lines. Named reactions come thick and fast in this section as well as the next one on pericyclic reactions. Almost two dozen different types of rearrangements are treated in substantial detail. Wittig chemistry is mentioned, but hydroboration– oxidation appears only in the functional group summary in the synthesis of alcohols. Grignard reagents, organolithiums and the Corey–House reagent are mentioned only in their context of adding to carbonyl groups. Selenation and organotransition metal compounds are omitted. On the last four pages of the book, functional group interconversions are summarized diagrammatically. Aliphatic hydrocarbons, halocarbons, alcohol, amines, and ethers are shown as products of synthesis; aldehyde, ketone, and carboxylic acid chemistry is diverse enough to require more than one diagram per class. Arenes are omitted from this section as the authors feel that aromatic chemistry has been adequately covered earlier. The book has virtually no biochemistry. Only the briefest of references to amino acids and sugars appears in the stereo-chemistry section. A few historical details about vitamin D are included in the section on rearrangements. The atypical numbering of isoquinoline appears on p 63, but the similar case of anthracene is omitted. Accepted protocols sometimes differ between England and the U. S.— on the bottom of p 21 the authors emphatically state that for aromatics “the use of an unbroken circle inside a six-membered ring is incorrect.” On the back cover the publisher promotes the book thusly: “…addresses the needs of a wide range of students requiring an introduction to the basics of organic chemistry.” I disagree—this book is definitely not for novices; it cannot be “skimmed” through to learn a lot of material quickly. Students who are just “dipping” into organic chemistry will ask how many carbons are in “stemane”. There are no practice problems. A lot of organic jargon is not formally defined or explained to any extent: phase transfer catalysts, mesom-

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Chemical Education Today edited by

Jeffrey Kovac University of Tennessee Knoxville, TN 37996-1600

eric effects, soft nucleophiles, and hard–soft acid–base (HSAB) terminology. Terms defined by diagram only include “scalemic” (non-racemic) mixtures, lactones, and 1,8-peri interactions—but a novice might wonder why there isn’t a 1,2-peri interaction in naphthalene. A slight artifact in a diagram would trap a novice, but an expert would know that “nonbonding MO” on p 8 applies not to the AO next to it, but to the relative energy of the MOs in the diagram. In my opinion, the book has been crafted extremely well for a very specific purpose: review. A person who has been

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away from organic chemistry (but who understood it very well at the time) can use this book effectively for a rapid review of any basic topic. The book is so highly compressed that every page is like a food with a rich sauce that needs to be slowly savored and slowly digested for maximum benefit. You may only glance into the book, but you can think about the chemistry for much longer. Eugene Gooch is in the Chemistry Department at Elon University, Elon NC 27244; [email protected].

Vol. 82 No. 6 June 2005



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