Cu(i)- and Au(i)-catalyzed regioselective oxidation of diynes: divergent synthesis of N-heterocycles

Catalyst-dependent oxidative cyclization of diynes with pyridine N-oxides is achieved using an amide directing group. Non-polarized and aminated alkyne could be selectively activated by copper and gold, thus leading to divergent synthesis of a range of pyrroles and dihydroindeno[1,2-c]pyrrol-3(2H)-ones. It should be noted that this difference might be attributed to the multicoordinated Cu center and the linearly aligned dicoordinated Au center.