Photochemical synthesis of bithienyl derivatives

Abstract

The application of a photochemical arylation of thienyl derivatives to the synthesis of bithienyl compounds is reported. The syntheses of 5-phenyl-2-propynylthiophene and 5-but-3-en-1-ynyl-2,2′bithienyl are described using as starting materials a phenylthienyl and a bithienyl derivative obtained by this method. Furthermore, the photochemical synthesis of halogenobithienyl ketones via the photochemical coupling of a halogenothiophene and 2-acetyl-5-iodothiophene is described. This methodology furnishes a new approach to the synthesis of natural bithienyls. All the synthesized compounds are singlet oxygen photosensitizers, and are, therefore, potentially bioactive compounds.