Palladium(0)-catalyzed phenylation of imidazo[4,5-b]pyridines

The tetrakis(triphenylphosphine)palladium(O)-catalyzed coupling of benzeneboronic acid with 2-chloro, 6-bromo and 6-bromo-2-chloro derivatives of 1- and 3-methylimidazo4,5-b]pyridines to novel 2-phenyl-, 6-phenyl- and 2,6-diphenylimidazo4,5-b]pyridines is described. The phenylation of imidazo4,5-b]-pyridines containing labile hydrogens was not successful.