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Paperback edition of Advances in Organometallic
Chemistry, Vol. 39. Robert West and F. Gordon A. Stone,
editors. Academic: New York, 1996. xi + 408 pp. Figs. and
Tables. 14.6 x 22.9 cm. $65.00.
How long is a silicon-silicon double bond? Written at
a level to which readers of this Journal are accustomed,
West and Stone's compilation answers this question and
many more, putting a degree of closure on a subject that has
grown and matured over the last 25 years.
It is important for chemists to realize that true
multiple bonds are not restricted to organic chemistry or
transition metal-metal bonds in complexes, but have been well
characterized and extensively studied throughout the boron,
carbon, and nitrogen families (groups 13, 14, and 15) of
the periodic table. As expected, the book places emphasis on
silicon chemistry, with individual chapters devoted to Si=E, (E =
Si, disilenes; C, silenes; N, iminosilanes; and P, As, phospha-
and arsa-silenes). Other chapters cover double bonds in
germanium and tin chemistry, boron-carbon multiple bonds,
and multiple bonding involving heavier group 13 elements.
Group 15 is represented in a chapter largely devoted to
heterobenzenes C5R5E'
(E' = N, P, As, Sb, Bi) complexed with iron in ferrocene fashion.
One might have been looking for an introductory
chapter to provide a general overview of the book title subject,
but no such chapter is present. However, sufficient diversity
of material in the eight chapters is present. A minimal
browse time of several hours will provide interesting reading and
a great deal of knowledge about an important subject in
modern chemistry. Chapter authors are indeed good, internal
consistency is high, and the book is up to date, with many
references through 1994 and a few into 1995.
Several textual quotations seem noteworthy in
characterizing impact one might draw from this book. Adrian
and Michael Brook state on page 151 that "...it is clear that
the status of silenes [Si=C compounds] has changed from
that of a rare oddity to a not uncommon occurrence". And
Renji Okazaki and Robert West add on page 232 that "Disilene
1 [(Mes)2Si=Si(Mes)2, Mes is the
mesityl group] has now become a common organometallic reagent."
Truly impressive is the wealth of information about silicon bond
multiplicity, once the "holy grail" of synthetic organometallic
chemists. Fully 38 molecular structures containing a
silicon-silicon double bond are listed in Table 1 (pp 234, 235). (By
the way, the silicon-silicon average double bond length is 2.16
Å.) Their now routine preparations are described in Volume
29 (1992) of Inorganic Syntheses, mainly via photolysis of
linear trisilanes.
While finding a specific piece of information (e.g.,
the tin-tin double-bond length) in a book of this sort might
be a bit frustrating, I would still recommend West and
Stone's opus as an informational storehouse of chemical
reactions, syntheses, physical properties, structural characteristics,
and spectroscopic data on a wide variety of main-group
multiply bonded compounds. The floodgates of new information
on the subject have seemingly closed, much as occurred in noble
gas chemistry, but is still ongoing
with transition metal-metal multiple bonding and with the fullerenes. An investment in
West and Stone's work at this time thus appears to be a good one.
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