A novel and efficient synthesis of porphine

meso-Tetra(i?-hexyloxycarbonyl)porphyrin was found to be converted into porphine, the mother compound of porphyrins, in a 77% yield when heated in aqueous sulfuric acid at 180 degrees C over 30 min under an inert atmosphere. The observation demonstrates that the substituted porphyrin serves as a novel and useful precursor for porphine. (c) 2006 Elsevier Ltd. All rights reserved.