The chemistry of pyrrolic compounds. XXXVII. Monobenzoporphyrins: The rhodoporphyrin of petroleum deposits

Abstract

A monobenzoporphyrin has been prepared from porphyrin derivatives containing a fused cyclo-hexanone ring. The cyclohexanone system can be constructed either before or after the porphyrin macrocycle has been synthesized. The spectroscopic properties of the monobenzoporphyrin are described and these support the proposal that such a species constitutes the rhodo-type series of porphyrins which have been isolated from some petroleum deposits.