Page 52 - Academic Press Encyclopedia of Physical Science and Technology 3rd InOrganic Chemistry

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Encyclopedia of Physical Science and Technology EN002c-73 May 21, 2001 13:59

Boron Hydrides

Herbert Beall
Worcester Polytechnic Institute
Donald F. Gaines

University of Wisconin-Madison

I. The Boron Hydrides: Their Discovery
and Formulas
II. The Structures of Boron Hydrides
III. Bonding Theories
IV. Isoelectronic Compounds: Boron Hydride
Anions and Carboranes
V. Reactions of Boron Hydrides
VI. Reactions of Boron Hydride Anions
VII. Reactions of Carboranes
VIII. Metallocarboranes
IX. The Future? Neutron Capture Tumor Therapy

GLOSSARY Electron deficient compound A compound with insuf-
ficient valence electrons to bond all adjacent atoms by
Boron hydride (borane) Aneutral compound containing ordinary two-center, two-electron bonds.
only the elements boron and hydrogen. Three-center bond A bond formed by the overlap of the
Boron hydride anion (borane anion) A negatively atomic orbitals of three atoms. Two electrons placed
charged ion containing only the elements boron and in the bonding orbital resulting from this overlap will
hydrogen. create a bonding situation.
Bridge bond In boron hydrides, boron hydride anions,
and their derivatives a three-center, two-electron bond
in which a hydrogen atom links two boron or boron and THE TERMS BORON HYDRIDES and boranes are
another element located on the edge of the structure. used synonymously for a family of chemical compounds
Carborane A compound containing at least one carbon containing only the elements boron and hydrogen. They
atom in a framework position that would be occupied do not occur in nature and must be synthesized in the
by a boron atom in a boron hydride. laboratory. Only about 30 of these neutral boron hydride

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