Page 86 - Arrow Pushing in Inorganic Chemistry A Logical Approach to the Chemistry of the Main Group Elements

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Group 13 Elements

Why did I decide to undertake my doctorate research in the exotic
field of boron hydrides? As it happened, my girlfriend, Sarah
Baylen, soon to become my wife, presented me with a graduation
gift, Alfred Stock’s book, The Hydrides of Boron and Silicon. I
read this book and became interested in the subject. How did it
happen that she selected this particular book? This was the time
of the Depression. None of us had much money. It appears she
selected as her gift the most economical chemistry book ($2.06)
available in the University of Chicago bookstore. Such are the
developments that can shape a career.
HerbertC.Brown.
In “From Little Acorns Through to Tall Oaks:
From Boranes Through Organoboranes,”
Nobel Lecture, December 8, 1979.
With these elements, we begin our introduction to the p block, home of all nonmetals (and of
a few metals) and of classic covalent chemistry. The elements are chemically rather diverse:
boron is a moderately electropositive nonmetal, whereas aluminum, gallium, indium, and
thallium are all metals. The covalent chemistry we will encounter in this chapter, therefore,
will still be somewhat limited, compared to what is to follow in the next chapters. Some
general remarks are in order:

• The elements are generally trivalent, although the monovalent state is also well esta-
blished for all the elements except boron. For thallium, the monovalent state is the
normal stable state, whereas for the lighter metals the monovalent state is reducing
and accessible only with considerable care and difficulty.
• With only six electrons in their valence shells, the trivalent compounds are generally
potent Lewis acids, forming a variety of adducts with bases (e.g., H N → BF ).
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Arrow Pushing in Inorganic Chemistry: A Logical Approach to the Chemistry of the Main-Group Elements,
First Edition. Abhik Ghosh and Steffen Berg.
© 2014 John Wiley & Sons, Inc. Published 2014 by John Wiley & Sons, Inc.

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