Synthesis of meso-tetraphenylthiaporphyrins bearing one inverted pyrrole

Abstract

2-Aza-21-thia-23-carba-5,10,15,20-tetraphenylporphyrin and its N-methylated analogue were synthesized and characterized. The synthesis utilizes [3+1] condensation of thiatripyrrin with 2,4-bis(α-hydroxy-α-phenylmethyl)pyrrole or 2,4-bis(α-hydroxy-α-phenylmethyl)-N-methylpyrrole in the presence of acid catalyst. This convenient process gives predominently the titled porphyrin. Reinversion of the pyrrole unit is observed by prolonging the reaction time.