Synthesis of 1,3-diynes via detelluration of bis(ethynyl)tellurides

Abstract

The synthesis of symmetric conjugated diyne systems with electron-withdrawing or electron-donating substituents via a palladium-catalyzed detelluration of bis(arylethynyl)tellurides and bis(alkylethynyl)tellurides is described. This procedure is effected under atmospheric conditions in DMF using Pd(OAc)2 as a catalyst and AgOAc as an additive in the presence of triethylamine. This route offers efficient access to conjugated diyne systems in short reaction time. X-ray crystallographic structure and solid-state conformation of bis(p-tolylethynyl)telluride show a supramolecular chain aligned along the b axis, sustained by C-H⋯π interactions. © 2011 Sociedade Brasileira de Química.