Pd-catalyzed Suzuki cross-coupling reactions of glycerol arylboronic esters

The reaction of glycerol with phenylboronic acid provided a mixture of cyclic glycerol esters, glycerol 1,2-phenylboronate (80%), and glycerol 1,3-phenylboronate (20%). The latter two products were formed from the esterification of the 1,2- and 1,3-hydroxyl groups, respectively. The glycerol phenylboronates were applied to the Pd-catalyzed Suzuki cross-coupling reactions with aryl halides. affording the corresponding biphenyl products in high yields. Excess glycerol phenylboronate was not required, and the Suzuki coupling reaction employed a simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine under mild reaction conditions. Arylboronic acid and pinacol arylboronic ester yielded similar results under the optimized reaction protocol. (c) 2008 Elsevier B.V. All rights reserved.