Chemical Education Today
Book & Media Reviews Functional Group Chemistry by James R. Hanson The Royal Society of Chemistry: Cambridge, 2001. 165 pp. ISBN 0-85404-627-5 Price unlisted. reviewed by Joel M. Karty
Presenting a full year of college-level organic chemistry in 150 pages is a formidable task. But James R. Hanson has accomplished just that in Functional Group Chemistry, one of a series of tutorial chemistry texts published by the Royal Society of Chemistry. This is intended to be a modular text, designed to provide “a concise account of the basic principles” underlying organic chemistry, and it is “written for first-year undergraduates”. The first of four chapters provides a synopsis of general principles. The remaining three divide functional groups into three broad classes: those whose reactivity is in the sigma bonding framework, those containing pi bonds, and those containing aromatic rings. Functional Group Chemistry is quite well organized and, for its size, is solid in its content. It falls short, however, in its effectiveness in promoting conceptual understanding. The organization of Functional Group Chemistry is, in general, well thought out. The division into the four chapters is logical, as is the order in which the chapters are presented. Within each chapter, the material is also presented in a sensible order. Chapter 1 begins by discussing the factors that give rise to the structure of functional groups; it moves on to the interrelationship between functional groups; and it ends with an overview of reaction types. In Chapters 2, 3, and 4, which focus on reactivity and reactions, Hanson’s presentation of each functional group is linear. He first introduces a functional group, next provides methods by which it is formed, and finally demonstrates reactions in which it is involved. One negative aspect of the organization, perhaps stemming from the compactness of the book, is that some reactions are introduced prematurely; they are used as examples before they are treated formally. For a book of its size, Functional Group Chemistry is remarkably complete. Hanson discusses in some detail the vast majority of the reactions and concepts that normally comprise an entire year of organic chemistry. He points out the importance of several reactions, such as C–C, C–N, and C– O bond formation, cyclization, and chain extension. Where appropriate, he identifies regiochemistry and stereochemistry. There are several instances, however, where the book is noticeably incomplete. The Hofmann rearrangement and several other staple reactions are described in words, but no examples or figures are provided. 1,2-Diols are said to be cleaved by sodium iodate, but the products are not given. Carbocation rearrangements are mentioned, but the impetus for such reactions is not explained. And, in electrophilic aromatic substitution, substituents on benzene are correctly identified as either ortho–para directors or meta directors, but not a single resonance structure of the Wheland intermediate is shown. Inclusion of such resonance structures would oth678
erwise help to explain the influence of those substituents. Functional Group Chemistry is, for the most part, clear and readable. The logical organization of reactions and concepts is certainly a positive. In addition, Hanson includes helpful figures that summarize the reactivity of key functional groups. In the case of aldehydes, the reactivity at the carbonyl carbon, the carbonyl oxygen, the proton at the α carbon, and the aldehyde hydrogen are provided in the same figure, enabling students to grasp a larger picture of the functional group. Another helpful feature is the identification of similarities in reactivity between functional groups. Hanson points out, for example, the similarities between carbonyl compounds, nitriles, and nitro compounds. Additionally, phenols are likened to enols, and pyrrole is likened to enamines. There are a number of aspects, on the other hand, which detract from the text’s clarity and readability. The density of information alone makes it difficult to absorb the material, and the number of references to earlier discussions of reactions and concepts is insufficient. Furthermore, Hanson, at times, appears to assume a background higher than that of a first-year undergraduate. On one occasion he explains reactivity with hyperconjugative effects, and on another occasion he explains reactivity with back bonding. Finally, there is a distinct lack of figures. Quite often, Hanson chooses to describe the nature of a reaction and its key intermediates with words rather than figures. Another shortcoming of Functional Group Chemistry is that mechanisms are de-emphasized. Although Hanson is good to point out whether a reaction is dictated by steric or electronic effects, he fails to provide mechanisms of many important reactions. This approach prevents students from obtaining a concrete sense of why reactions have the regioselectivity and stereoselectivity that they do. It promotes memorization over understanding, which is a more frustrating route to learning organic chemistry. The in-chapter and end-of-chapter exercises and problems carry with them both positives and negatives. They are well written and challenging, and many of them bring several concepts together. As a result, students would be coerced to see the larger picture and would stand to learn quite a lot. However, many of the problems are too difficult in relation to the material covered. Furthermore, there are mixed messages with regard to reaction mechanisms. Within the chapters, mechanisms are scarce, and those that are given are fairly simplistic. Yet in the end-of-chapter problems, students are routinely asked to devise quite complex mechanisms. It is therefore easy to imagine that students might become overwhelmed and frustrated. Given its density and brevity and the apparent requirement of previous organic chemistry knowledge, Functional Group Chemistry is inappropriate as a stand-alone text for firstyear organic students. It is also difficult to imagine using it as a supplement to a traditional textbook, since the textbook would presumably provide the same material in greater depth and with better clarity. The end-of-chapter problems in Functional Group Chemistry, however, would provide excellent exam and supplemental homework questions, and would be
Journal of Chemical Education • Vol. 79 No. 6 June 2002 • JChemEd.chem.wisc.edu
Chemical Education Today
appropriate given the greater emphasis on reaction mechanisms in the traditional textbook. Perhaps the best use for Functional Group Chemistry, then, is for students returning after having had a year of organic chemistry, either for a quick reference, or for an in-depth review in studying for a standardized exam. Joel M. Karty is in the Department of Chemistry, Elon University, Elon, NC 27244;
[email protected].
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