Palladium-catalyzed sequential [3+2] cyclization/C-H activation of o-iodostyrenes with cyclopropenones as C2 synthons

Abstract

Herein we report a novel palladium-catalyzed synthesis of diverse dihydroindeno[2,1-a]indenes by the reaction of o-iodostyrenes with cyclopropenones. This protocol involves a [3+2] cyclization/C-H activation sequence, forming a C(sp2)-C(sp2) and two C(sp2)-C(sp3) bonds. This procedure represents an innovative method for assembling of tetracyclic dihydroindeno-indenes utilizing cyclopropenones as a new C2 synthons.