Palladium-Catalyzed Annotation of Acyloximes with Arynes (or Alkynes): Synthesis of Phenanthridines and Isoquinolines

摘要

Palladium-catalyzed carbon-heteroatom bond formation has been the subject of intense research for the past decades. Kitamura and Narasaka have developed an elegant palladium-catalyzed carbon-nitrogen bond-forming process by exploring the chemistry of readily accessible acyloximes. In contrast to other palladium-catalyzed reactions where the nitrogen atom of C=N-containing substrates acted as a nucleophile, the acyloximes act firstly as an electrophile to add oxidatively to the Pd~0 complex. The newly generated aza-palladium(II) complex could then react with internal olefins to form cyclic product Scheme 1, Eq. (1).