Synthesis of aryl boronic acids

摘要

A process for producing an aryl boronic acid which comprises: (i) directly combining an aryl Grignard reagent with a trialkyl borate at a temperature of -10º C to 0º C in a reaction vessel, wherein the mole ratio of the trialkyl borate to the aryl Grignard reagent is about 1.2, and wherein a reaction mixture containing an aryl boronic acid alkyl diester is produced; and (ii) subjecting the reaction mixture in to conditions effective to hydrolyze the aryl boronic acid alkyl diester to yield the aryl boronic acid. The aryl boronic acid is preferably, phenyl boronic acid or 4-fluorophenyl boronic acid