FORMATION OF TETRABENZOPORPHINE SKELETON BY THE REACTIONS OF PHTHALIMIDE WITH ZINC CARBONATES

The high temperature reactions of phthalimide potassium salt (PIK) with various zinc carbonates were carried out. The reaction of PIK with zinc acetate yielded tetrabenzoporphinato zinc (ZnTBP). Tetra-tert-butyltetrabenzoporphinato zinc (ZntBu4TBP), whose four tert-butyl substituents were positioned on the TBP periphery, was also prepared in a similar way using the 4-tert-butylphthalimide potassium salt (4-tBuPIK). These results were explained on the basis of the function of zinc acetate as the meso-methine carbon source of the TBP structure. The use of zinc phenylacetate instead of zinc acetate in the reaction of PIK led to the production of meso-phenyl substituted ZnTBPs, although they were different in the number of meso-phenyl substituent(s). The attempt to introduce alkyl residues at the meso-position(s) by the reaction of PIK in the presence of zinc alkylacetate having a long alkyl chain was not successful, except for the substitution of the methyl group using zinc propionate.