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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.
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