Construction of meta-Aryl Acetophenone Derivatives via Pd-Catalyzed Arylation/Dehydrogenative Aromatization.

Herein, we report a palladium-catalyzed domino arylation/dehydrogenative aromatization of acylcyclohexenes to synthesize meta-aryl acetophenone derivatives. This strategy achieves a previously elusive formal meta-C-H arylation of ketones, even with heteroaryl halides. It allows the late-stage introduction of fluorophores and supramolecular motifs, and the robustness is demonstrated by converting biaryl compounds to cumulenes and an AIE fluorescent Na+ probe. Mechanistic investigations revealed a radical process involving an aryl radical as a hydrogen atom transfer reagent.