New approach for post-functionalization of meso-formylporphyrins†
Abstract
A strategy for the post-functionalization of readily accessible meso-formylporphyrins affording meso-(2-imidazolyl)-porphyrins, containing substituents at the 4,5-positions of the imidazole fragment is developed. The reaction of 5-formyl-10,20-diarylporphyrins with phenanthrene- or phenanthroline-5,6-dione and ammonium acetate provides 5-(areneimidazol-2-yl)-10,20-diarylporphyrins with high yields. This methodology is used to prepare a set of representatives of this new type of substituted porphyrins. The distribution of the frontier orbitals of this class of compounds is evaluated by means of DFT calculations.