Ru(II)-Catalyzed Oxidative Olefination of Benzamides: Switchable Aza-Michael and Aza-Wacker Reaction for Synthesis of Isoindolinones

摘要

Selective tandem oxidative C-H olefination-azaMichael/aza-Wacker reaction of N-arylbenzamides is achieved by fine-tuning between base and additive to access valuable 3-oxoisoindolinyls and 3-oxoisoindolinylidenes, respectively. Careful optimization and control experiments provides a guiding principle in the design of a proposed catalytic cycle. The copper-iminium complex acting as a precursor for the binding of Ru catalyst was isolated and confirmed by X-ray diffraction. The versatility of this catalytic system has been demonstrated by the synthesis of biologically relevant molecules.