Synthesis of Bistricyclic Aromatic Enes Containing Bifluorenylidene Units via Pd-Catalyzed Tandem Suzuki Coupling/Heck Cyclization Reaction.

Abstract

A variety of bifluorenylidene-based bistricyclic aromatic enes (BAEs) and their derivatives have been prepared via the palladium-catalyzed Suzuki coupling/Heck cyclization tandem reaction in one pot. In the new scheme 2-bromophenyl trifluoromethanesulfonate and similar derivatives were chosen as one of reaction substrates, which could undergo tandem Suzuki coupling/Heck cyclization reaction with suitable arylboronic acid ester substrates to afford the expected BAEs and their derivatives. In the newly designed scheme, the raw materials are easier to obtain and can be applied to the synthesis of more BAEs and their derivatives.