Cofacial Porphyrin−Ferrocene Dyads and a New Class of Conjugated Porphyrin

A porphyrin−ferrocene dyad has been synthesized in which there is close face-to-face contact between the two aromatic systems, providing a model for heterobimetallic polymers based on the same repeating unit. Attempts to synthesize the 2:1 adduct instead led to a remarkable intramolecular Heck-type cyclization which planarizes the system and extends the conjugation.