Controllable assembly of the benzothiazole framework using a C[triple bond, length as m-dash]C triple bond as a one-carbon synthon.

A concise and efficient protocol to assemble diverse benzothiazole derivatives in high yields was provided via copper catalyzed tandem cyclization with o-haloanilines, elemental sulfur and terminal alkynes as raw materials. In this protocol, C atoms on the C[triple bond, length as m-dash]C triple bond were controllably involved in the construction of the benzothiazole framework and multiple carbon-heteroatom bonds through divergent routes.