Porphyrins with exocyclic rings. Part 23: Synthesis of porphyrins with large exocyclic rings-cyclohexadeca[b]pyrroles and porphyrins therefrom

Cyclohexadecanone and other large ring ketones undergo Knorr-type condensations with phenylhydrazones to afford cycloalka[b]pyrroles. A series of dipyrroles incorporating 16-membered rings were prepared from these pyrroles and used to synthesize porphyrins with large exocyclic rings.