Direct Access to Dihydrobenzoimidazo[2,1‐<i>a</i>]isoquinolines through Ruthenium‐catalyzed Formal [4+2] Annulation

Abstract

Abstract A facile and straightforward synthesis of benzoimidazo[2,1‐ a ]isoquinolines through Ru(II)‐catalyzed [4+2] annulation reaction of 2‐aryl benzimidazole and styrene has been explored. Tentative mechanistic studies imply the current reaction involves sequential C−C/C−N bond formation through the ortho C−H activation of 2‐aryl benzimidazole followed by C−N reductive elimination. This newly developed strategy is widely applicable and tolerates various 2‐arylbenzimidazole and vinyl derivatives, and allows the attractive vehicle for direct construction of diverse C6‐substituated benzoimidazoisoquinoline scaffold in good yields. magnified image