Novel Route for Obtaining Isomeric Benzo[b]thiophenoindoles

Abstract

We describe a novel route for synthesis of benzo[b]thiopheno[2,3-e]- and benzo[b]thiopheno[3,2-f]indoles. As the starting compounds, we used the corresponding annelated isatins obtained by the Sandmeyer reaction. We have established that reduction of the latter to the corresponding unsubstituted benzo[b]thiophenoindoles depends both on the nature of the substituent and on the reaction conditions.