Rh(iii)-catalyzed oxidative C–H annulation of 6-arylpyridazin-3(2H)-ones: direct access to diarylpyridazino[6,1-a]isoquinolin-5-ium-3-olates

Abstract

A novel strategy has been developed for the synthesis of diarylpyridazino[6,1-a]isoquinolin-5-ium-3-olate frameworks through a Rh(III)-catalyzed C–H annulation of 6-arylpyridazin-3(2H)-ones with internal alkynes by means of C–H bond activation. This is the first report on ortho-C–H bond annulation of 6-arylpyridazin-3(2H)-ones with alkynes to afford angularly fused heterocycles in good yields with high functional group tolerance. This method offers a facile and practical approach to structurally diverse mesoionic scaffolds of pharmaceutical relevance.d6ra01670g-s