Cu-catalyzed cross-dehydrogenative coupling reactions of (benzo)thiazoles with cyclic ethers.

Copper-catalyzed cross-dehydrogenative coupling (CDC) reactions of (benzo)thiazoles with cyclic ethers were developed under mild conditions. In particular, the formation of C-C bonds via the CDC reactions between non-benzo-fused azoles and ethers are reported for the first time. In addition, the acetals, known as the masked 2-thiazolecarboxaldehydes, could be successfully obtained by this CDC reaction. The preliminary mechanism and supportive DFT calculations are discussed as well.