Benzo- and Thieno-Annulated Tetracenes: A One-Pot Synthesis via Cross-Dehydrogenative Annulation

Org Lett. 2020 Jun 5;22(11):4160-4163. doi: 10.1021/acs.orglett.0c01244. Epub 2020 May 8.

Abstract

A facile method for the direct cross-annulation of unfunctionalized tetracene is reported. The one-pot oxidative cross-dehydrogenative coupling (CDC) between tetracene and aromatic compounds, such as benzene or 2-methylthiophene, furnished annulated products with an extended π-network. Moreover, relative to the benzo-annulated tetracenes, thieno-annulated tetracenes exhibited notably improved photooxidative stability. This behavior stands in sharp contrast with that of tetracene and its derivatives, such as rubrene, which readily engage in photoinduced oxidation reactions.