Amidines for Versatile Ruthenium(ll)-Catalyzed Oxidative C-H Activations with Internal Alkynes and Acrylates

摘要

Cationic ruthenium complexes derived from KPF6 or AgOAc enabled efficient oxidative C-H functionalizations on aryl and heteroaryl amidines. Thus, oxidative annulations of diversely decorated internal alkynes provided expedient access to 1 -aminoisoquinolines, while catalyzed C-H activations with substituted acrylates gave rise to structurally novel 1-iminoisoindolines. The powerful ruthenium(ll) cata lysts displayed a remarkably high site-, regio- and, chemose-lectivity. Therefore, the catalytic system proved tolerant of a variety of important electrophilic functional groups. Detailed mechanistic studies provided strong support for the cationic ruthenium(ll) catalysts to operate by a facile, reversible C-H activation.