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 the assembly of tetracyclic dihydroindeno-indenes utilizing cyclopropenones as a new C2 synthon.