meso-β Dibenzo[a,g]corannulene-Fused Porphyrins

FeCl3-mediated oxidative fusion of meso-linked dibenzo[a,g]corannulene porphyrin dyads 6M afforded fused porphyrins 7M bearing a five-membered ring connection, but similar oxidation of beta-linked dyads 9M provided fused porphyrins 10M bearing a six-membered ring connection, both in a regiospecific manner. While fused dyads 10M exhibit modestly red-shifted absorption and fluorescence profiles, fused dyads 7M display characteristically red-shifted absorption bands reflecting antiaromatic dehydropurpurin electronic networks.