Chemical Education Today
Reductions by the Alumino- and Borohydrides in Organic Synthesis, 2nd edition Jacqueline Seyden-Penne. Wiley-VCH: New York, 1997. 224 pp. ISBN 0471190365. $74.95.
This book focuses entirely on the aluminohydride and borohydride reducing agents. It condenses a large body of information into a valuable user-friendly resource for synthetic organic chemists. The author states that “This second edition has been broadly updated, but it is no longer exhaustive. As in the previous edition, the examples are selected in order to cover problems that are frequently encountered in synthesis.” The first chapter (13 pages) gives an excellent summary of the approximately two dozen most widely used aluminohydride and borohydride reagents. Information is presented on the main applications of each reagent and its solubility characteristics, stability, and handling requirements. Cross-references are liberally given to subsequent chapters where more complete reactivity profiles and examples are found. Chapters two through five (155 pages) detail reduction of the main functional groups by these reagents. Chapter two covers reductions of carbon-heteroatom single bonds (C–Hal, C–O, C–N, C–P). Reagents capable of effecting a desired single-bond cleavage are described, as are mechanistic considerations of the process. Chemoselectivity and regioselectivity are duly noted. Chapter three is concerned with reduction of double bonds (C=C, C=O, C=N) and is by far the largest chapter in the book. Reduction of carbon–oxygen double bonds is organized by functional group. The examples for aldehydes and ketones illustrate the potential for selectivity in the presence of other functional groups; the control of stereoselectivity, including a discussion of the factors favoring the Felkin– Ahn or Houk models; a survey of enantioselective reducing agents, particularly those developed in recent years; and the influence of neighboring substituents on stereoselectivity as the result of chelation control. These concerns and further consideration of conditions for partial reduction are given for carboxylic acid derivatives. Similar examples are included for reduction of carbon–nitrogen double bonds. Carbon–carbon and carbon–nitrogen triple bonds, both isolated and conjugated, are treated in Chapter four. The examples illustrate the potential for chemo-, regio, and stereoselectivity. Chapter five addresses the reduction of “other derivatives”, including nitro and nitroso derivatives, azides, organometallics, sulfides (sulfoxides, sulfones, and amine oxides), phosphine oxides and phosphates, silyl derivatives, and boron reagents. Seyden-Penne concludes with a large table (11 pages) that “shows at a glance” the various methods by which major functional groups can be obtained by hydride reduction with cross references to the appropriate sections of the text. This book is a thorough and dense compilation of experimental results and observations that highlight selectivity at every level as well as experimental practicality. The 10-page index appears to be well organized and the referencing is extensive (more than 1000 references in 33 pages). Given the prevalent role of hydride reduction reactions in organic synthesis, many practitioners will want to have ready access to this book, and it is a must for all science libraries. R. C. Hoye Department of Chemistry Macalester College St. Paul, MN 55105-1899
JChemEd.chem.wisc.edu • Vol. 76 No. 1 January 1999 • Journal of Chemical Education
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