Rhodium-catalyzed regioselective c7ar-functionalization of tryptophan with quinones and its late stage peptide exemplification

Abstract

Pivaloyl-directed Rh(III)-catalyzed regioselective C7Ar-H functionalization of protected tryptophans were accomplished with 1,4-benzoquinones, furnishing a series of quinone-appended tryptophan-based unnatural amino acids in high yields. Further, the late stage functionalization on tryptophan-containing dipeptides was achieved with 1,4-benzoquinones in moderate reactivity.