Thiaheterohelicenes 1. Synthesis of unsubstituted thia[5]-, [9]- and [13]heterohelicenes

Abstract

The unsubstituted thiaheterohelicenes, 5,8-dithia[5]helicene, 1, 5,8,11,14-tetrathia[9]helicene, 2, and 5,8,11,14,17,20-hexathia[13]helicene, 3, have been prepared. The key reaction was the oxidative photolysis of 1,2-diaryl-substituted ethenes which were prepared by Wittig-Horner or McMurry reactions. © Acta Chemica Scandinavica 1996.