Efficient Synthesis of Benzo Fused Tetrathia[7]helicenes

Abstract

An efficient route toward the synthesis of symmetrical and unsymmetrical benzo fused tetrathia[7]helicenes substituted with electron donor (ED) and electron acceptor (EA) groups is reported. A common, readily available precursor 1,2- bis-(2-thienyl)benzene was used to synthesize different helicenes through a Wittig reaction, Stille coupling, and modified oxidative photocyclization.