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 possibleat this levelto 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 reactionssubstitution, addition and elimination; that these reactions involve only three types of reagentnucleophiles, electrophiles and radicals; and that there are only two effectselectronic and steric There is no discussion of bonding that involves orbital theory, norin formal termsof 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 alpha,ß-unsaturated 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 nucleophile 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.