Palladium-Catalyzed Controllable Reductive/Oxidative Heck Coupling between Cyclic Enones and Thiophenes via C-H Activation

Org Lett. 2019 Dec 6;21(23):9545-9549. doi: 10.1021/acs.orglett.9b03721. Epub 2019 Nov 14.

Abstract

Herein, we report a straightforward, environmentally friendly, and controllable palladium/ligand catalytic system to enable reductive/oxidative Heck reactions of cyclic enones with thiophene or furan derivatives via C-H activation. The key to this tunable reaction is the appropriate intercepting thienyl-Pd(II)-enolate during the enolization process. Such a controllable and economic protocol would not only provide efficient methods to construct various value-added β-heteroarylated cyclic ketones/enones but also shed light on developing other conjugate addition reactions via C-H activation.