CuI/TMEDA-Catalyzed Annulation of 2-Bromo Alkynylbenzenes with Na2S: Synthesis of Benzo[b]thiophenes

A copper-catalyzed thiolation annulation reaction of 2-bromo alkynylbenzenes with sodium sulfide has been developed. In the presence of CuI and TMEDA, a variety of 2-substituted benzo[b]thiophenes were readily prepared in moderate to good yields by the reaction of 2-bromo alkynylbenzenes and Na2S center dot 9H(2)O.