1.http://www.chem.wisc.edu/areas/reich/chem842/_chem842-07-boron.htm
(Boron Chemistry)
2.The general formula for boric acid esters is B(OR)3. The
lower molecular weight esters such as methyl, ethyl, and phenyl are most
commonly referred to as methyl borate, ethyl borate, and phenyl borate,
respectively. Some of the more common boric acid esters used in industrial
applications are trimethyl borate, trimethyl borate azeotrope, triethyl borate,
triethyl borate azeotrope, tri-n-propyl borate,
triisopropyl borate, tri- n-butyl borate, triphenyl borate,
tricresyl borate, trimethoxyboroxine, and triisopropoxyboroxine. Most reported
boric acid esters are trialkoxy or triaryloxy boranes. The esters range from
colorless low boiling liquids to solids that possess high melting points. Boric
acid esters usually have an odor similar to the hydroxy compound from which they
are derived. Alkyl boric acid esters derived from straight-chain alcohols and
aryl boric acid esters are stable to relatively high temperatures.
Trialkoxyboranes from branched-chain alcohols are much less stable, and boranes
from tertiary alcohols can even decompose at 100°C. Decomposition of
branched-chain esters leads to mixtures of olefins, alcohols, and other
derivatives. Methods used for the preparation of borate esters, include the
esterification of boric acid or boric oxide,
B2O3, and transesterification.
Most methyl borate is produced by Morton International and used captively to
manufacture sodium borohydride. Aryl borates produce phenols when in contact
with water and are therefore subject to shipping regulations governing such
materials and must carry a Corrosive Chemical label. Lower alkyl borates are
flammable; methyl, ethyl, and butyl borates must be stored in approved areas.
Other compounds are not hazardous. Boric acid esters are used in the production
of sodium borohydride, gas fluxing, as polymer additives, in hydraulic fluids
and lubricants, as biocides, and in hydrocarbon oxidation. (source: http://mrw.interscience.wiley.com/emrw/9780471238966/kirk/article/boridock.a01/current/abstract)
3.Triphenyl borate
is a Lewis acid which act as reaction rate
accelerators or inhibitors in polycarbonate polymerization by enhancing the electrophilicity of the carbonyl
group.
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