Organic Chemistry, Sixth Edition (Solomons, T.W. Graham)

12 December 1996. Chemical Education Today. Organic Chemistry, Third Edition. Francis A. Carey. McGraw-Hill: New York, 1996; xxvi + 1151. + A-87 + I-3...
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Chemical Education Today

Reviews Organic Chemistry, Third Edition Francis A. Carey. McGraw-Hill: New York, 1996; xxvi + 1151 + A-87 + I-31 pp. The area of organic chemistry is blessed with more than its share of excellent introductory textbooks. The majority of these books follow the functional group approach that was pioneered by Morrison and Boyd, and this works well for the standard American sophomore year-long courses. F. A. Carey’s excellent textbook is now available in its third incarnation, and continues to maintain the high standards set in the earlier editions. The figures and diagrams in the third edition have been completely revised and for the most part these make good use of both color and design. In some textbooks, color is used purely for its own sake, needlessly increasing the cost of the book without adding to its clarity. Although this charge can be laid against Carey’s text in places (e.g., the pastel colored backgrounds for the figures and schemes add very little), the excellent presentation of molecular models and conformations cannot be faulted. Organic chemistry remains a very visual subject, and the clear presentation of three-dimensional molecular structures is pedagogically valuable. The author notes in the introduction that “…functional group analysis such as the Lucas, Hinsberg and Tollen’s test, which are almost never used in the modern practice of organic chemistry, are not included”. While this is certainly true, these tests do illustrate some important chemical concepts and processes, and perhaps remain somewhat relevant. The author continues to stress the use of reaction mechanisms, and this remains a strong point in the new edition. The heart and soul of modern organic chemistry revolves around these concepts, and this framework is essential for a textbook of this type. The organization of the new edition is similar to the previous version, starting off with a chapter on chemical bonding, and proceeding with chapters on alkanes and conformational analysis. Chapter 4 (“Alcohols and Alkyl Halides”) introduces the concepts of acidity and basicity, and the chemistry of alcohols including SN1 and SN2 reactions. Two chapters are designated to the chemistry of alkenes, and Chapter 7 covers stereochemistry (including the use of Fischer projection formulae). The stereochemical concepts are nicely tied in with previously discussed chemical reactions and the principle of stereoselectivity is introduced at this stage. The expected chapters on nucleophilic substitution, alkynes, conjugated dienes, aromaticity, and electrophilic aromatic substitution reactions follow. Chapter 13 allocates 50+ pages to spectroscopy and covers the standard materials. I believe that it is a mistake to continue to use so many outdated 60 MHz proton NMR spectra (although the author addresses this point in the introduction), but this is a minor quibble. The spectra would be clearer, however, without the chart paper backgrounds and this change might be considered for the 4th edition. Chapter 14 covers organometallic chemistry

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(primarily Grignard and organolithium reactions) and subsequent chapters relate the functional group chemistry of alcohols, ethers, aldehydes, ketones, carboxylic acids, esters, amines, and so on. It is nice to see the inclusion of some sulfur chemistry, particularly given the biological relevance of this area. The final chapters include, inevitably, carbohydrates, lipids, and amino acids/ peptides/proteins. Nucleic acids are covered in minimal detail, but this is appropriate as time does not really permit this material to be covered in sophomore-level organic chemistry courses. Molecular modeling exercises are suggested at the end of each chapter, and while a few of these are a little contrived, the principle is laudable. A number of short essays are included within the main chapters, and some of these are new including the interesting topics “enediyne antibiotics” and “chiral drugs”. These are really just short snippets, but they are all the better for that and add life to the text. The author has attempted to make the writing style less formal, and has succeeded to a certain extent. A dryer style may be preferred by some instructors, but in my experience students find this to be less accessible and I am pleased to see the author take this important stylistic consideration on board.

Timothy D. Lash Illinois State University, Normal, IL 61790-4160

Organic Chemistry, Sixth Edition T. W. Graham Solomons. Wiley: New York, 1996; xxvii + 1290 pp. Figs., tables, and illus. 19.1 × 26.3 cm. $90.95. A review of the fifth edition of this text appeared in this Journal (1992, A251). Much of that review still applies to this edition. Visually, the text continues to be improved. The use of color is clearer. Color is employed very effectively when illustrating nucleophiles and leaving groups. Most reaction mechanisms are set apart by a gray title bar with red lettering, making them easier to find. Organization has changed little. The radical reactions chapter has been delayed to Chapter 9, while spectroscopy has been advanced to Chapter 13, ahead of the aromatic chemistry chapters. Alcohol nomenclature is introduced in the same chapter as alkane nomenclature. The chapters on amines and β-dicarbonyl chemistry have been switched, but none of these are really earth-shattering changes. The content also has changed little, other than in the spectroscopy chapter and in Chapter 3 (An Introduction to Organic Reactions: Acids and Bases). The biggest improvement in this edition is the use of 300 MHz proton NMR spectra, as opposed to the 60 MHz spectra used in previous editions. This eliminates most of the “second-order” coupling problems, and helps the beginning student learn to interpret NMR spectra more easily. The discussion of 13 C NMR has been enhanced with better spectra as well. The discussion of NMR has also been improved in this chapter.

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Chapter 3 continues to be a strong chapter, and has been enhanced by the use of more organic examples. The use of curved arrows is introduced clearly using acidbase reactions, resonance, and a few organic reactions. If students can master the concepts in this chapter, then they will have a good background for many of the reactions and mechanisms that they will encounter later. One of the strengths of the text is the large number of problems, both within and at the end of the chapters. Many of these problems have been revised, and several new end-of-chapter problems have been added to each chapter. The review problem sets, which follow Chapters 12 and 21, have been little changed, but are great for helping students to study for finals or to review at the beginning of the semester. Typographical errors appear to be few. There seems to be an extraneous arrow in the scheme at the top of page 888, and an arrow and the NH2 group on the enzyme are missing from the scheme at the top of page 828 (compare with the corresponding drawing on page 794 of the fifth edition). The page headings on the review problem sets are deceiving. The first set still has the Chapter 12 heading on page 532. The second set is entitled “First Review Problem Set”, and has that heading on pages 995 & 997, and has the Chapter 21 heading on pages 994, 996, & 998. Overall, this edition is not a large change from the previous one. The improvements in the visual presentation and in NMR are very positive. This text should be a strong candidate when choosing a book for a twosemester organic chemistry sequence.

Bruce A. Hathaway Southeast Missouri State University Cape Girardeau, MO 63701

A Primer to Mechanism in Organic Chemistry Peter Sykes. Longman Scientific & Technical: Essex, England, 1995; xii + 177 pp. 15.9 × 23.3 cm. Most organic chemists will be familiar with A Guidebook to Mechanism in Organic Chemistry by Peter Sykes. The six editions of the Guidebook (first published in 1961; 6th edition published in 1986) have helped several generations of graduate students assimilate a mechanistic view of organic chemistry. The Primer represents a significant departure from both the style and content of the Guidebook. In the author’s own words: “The Primer is a considerably simpler book, one that seeks to set out the basic, underlying framework of organic reaction mechanisms… The basic premise is that it is possible—at this level—to make some sense out of the apparent overfacing complexity of organic chemistry on the basis of three underlying axioms: that there are only three types of reactions—substitution, addition and elimi-

nation; that these reactions involve only three types of reagent—nucleophiles, electrophiles and radicals; and that there are only two effects—electronic and steric… There is no discussion of bonding that involves orbital theory, nor—in formal terms—of chemical energetics...” The empirical categorization based on reaction type and reagent type is appealing in its simplicity, yet less than obvious in its application. For example, net substitution at acyl carbons does not appear in the substitution chapter. Hydrolyses of RCOX under neutral or basic conditions appear in the chapter devoted to addition reactions in the section dealing with nucleophilic reagents. Hydrolysis under acidic conditions is discussed in the chapter on elimination reactions in the section dealing with electrophilic reagents. I suspect that an empirical classification based on the net transformation would have been more student-friendly than a categorization based on the initial step of the mechanism. This latter approach presupposes a knowledge of the mechanism in order to locate a particular reaction in the book! The greatest strength of the book is that experimental evidence is routinely presented in support of mechanistic proposals. Alternative mechanisms are often presented along with the “correct” mechanism. Arguments are well-formulated and generally presented at an appropriate level. A variety of experimental techniques (primarily isotopic labeling and simple kinetic methods) and results are invoked throughout the book; students are consequently exposed to some of the tools used to solve real mechanistic problems. Coverage is, however, uneven. For example, the dozen pages given to the section on radical substitution reactions are very well done and include a good discussion of relative rates in explaining and predicting reaction products. In contrast, only a single page is devoted to the Diels–Alder reaction and only two pages to conjugate addition reactions of α,βunsaturated carbonyl compounds. This is perhaps understandable in light of the author’s decision not to invoke “orbital theory [or] chemical energetics.” The selectivity of the Diels–Alder reaction is truly inexplicable without some consideration of orbitals. Likewise, because the fundamental distinction between thermodynamically controlled reactions and kinetically controlled reactions is never explicitly addressed anywhere in the book, the discussion of direct (1,2-) verses conjugate (1,4-) addition reactions provides no mechanistic insights regarding observed regioselectivities. Often, there are explanations based on the steric and electronic effects of substituents in (de)stabilizing transition states or reactive intermediates without regard for corresponding (de)stabilization of ground state structures. My own experience has been that students have great difficulty in distinguishing between kinetic and thermodynamic stability. This Primer does little to make these concepts any clearer for students. The Primer contains an unfortunate number of errors. Many are undoubtedly typographical, but other more serious errors appear to be a consequence of the effort to oversimplify the level of presentation. A few examples: (i) hydroxide (not water) is shown as the nu-

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Reviews cleophile reacting with the tert-butyl cation in the solvolysis of tert-butyl bromide (p 17); (ii) in an ipso (electrophilic aromatic) substitution reaction, the proton (H+) is described as “...an extremely good leaving group” (p 47); and (iii) in the hydroxide-promoted 1,1-elimination of HCl from chloroform, the reactive intermediate, dichlorocarbene, is said to be “...slowly hydrolysed to the end products...” (whereas in fact this is the fast step in the overall hydrolysis) (p 140). On a more positive note, the inclusion of many examples from polymer chemistry in a completely integrated fashion is another strength of the Primer. A book of this length and scope would be most appropriate as a supplement to the second-year organic lecture course in the United States. Some parts of the Primer may be of use to American students, but on the whole, I am reluctant to recommend it for the reasons outlined above. The effort to demystify the myriad mechanisms we present to beginning students of organic chemistry is a worthwhile goal, but one which is not fully achieved in this book.

Stephen E. Branz San Jose State University, San Jose, CA 95192-0101

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Journal of Chemical Education • Vol. 73 No. 12 December 1996