Remarkable co-catalysis by copper(I) oxide in the palladium catalyzed cross-coupling of arylboronic acids with ethyl bromoacetate.

Copper(I) oxide can effectively co-catalyze the Suzuki type cross-coupling reactions of arylboronic acids with ethyl bromoacetate. As an alternative protocol for introducing the methylenecarboxy group into functionalized molecules, this reaction occurs in the absence of highly toxic thallium compounds or special ligands and should be convenient and practical.