Synthesis and spectroscopic and electrochemical properties of an axially symmetric fullerene-porphyrin dyad with a rigid pyrrolo[3,4-c]pyrrole spacer.

A new approach to porphyrinofullerene donor-acceptor dyads, based on consecutive 1,3-dipolar cycloaddition of azomethine ylides, generated from bis-aziridinedicarboxylate, to C60 and to porphyrin with a maleimidophenyl substituent, was developed. A synthesis of the axially symmetric porphyrin-fullerene-C60 ensemble 5 with a novel rigid pyrrolo[3,4-c]pyrrolic linker was realized. Theoretical, electrochemical, and spectroscopic studies of compound 5 showed that it is capable of forming a charge-separated state.