Wikipedia
Linking: http://en.wikipedia.org/wiki/Phenylboronic_acid
Material
Safety Data Sheet: http://www.chemcas.com
Phenylboronic acid, or benzeneboronic acid, is prepared by the reaction of the
Grignard reagent PhMgBr with B(OMe)3. It and its aryl-substituted
derivatives are commonly used as building blocks in synthetic organic
chemistry—most often in the Suzuki coupling reaction, in which a boronic acid
reacts with an organic halide to form a carbon–carbon bond. Boronic acids’
reactions with 1,2- and 1,3-diols are useful for saccharide recognition. http://portal.acs.org/
Structurally,
boronic acids are trivalent boron-containing organic
compounds that possess one alkyl substituent (i.e.,
a C–B bond) and two hydroxyl groups to fill the remaining
valences on the boron atom (Figure 1.1). With only six
valence electrons and a consequent deficiency of two
electrons, the sp2-hybridized boron atom possesses a
vacant p orbital. This low-energy orbital is orthogonal
to the three substituents, which are oriented in a trigonal
planar geometry. Unlike carboxylic acids, their carbon
analogues, boronic acids are not found in nature. These
abiotic compounds are derived synthetically from primary
sources of boron such as boric acid, which is made by
the acidification of borax with carbon dioxide. Borate
esters, the main precursors for boronic acid derivatives,
are made by simple dehydration of boric acid with alcohols.
The first preparation and isolation of a boronic acid
was reported by Frankland in 1860 [1]. By treating diethylzinc
with triethylborate, the highly air-sensitive triethylborane
was obtained, and its slow oxidation in ambient air
eventually provided ethylboronic acid. Boronic acids
are the products of the second oxidation of boranes.
Their stability to atmospheric oxidation is considerably
superior to that of borinic acids, which result from
the first oxidation of boranes. The product of a third
oxidation of boranes, boric acid, is a very stable and
a relatively benign compound to humans http://www.wiley-vch.de/
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