Stepwise synthesis of symmetrically substituted azaporphyrins

Abstract

Porphyrins that have one nitrogen atom instead of a methine bridge at the meso-position are named monoazaporphyrin. This class of porphyrinoid compounds though first investigated by Fischer in the thirties of the last century is still less common compared to other porphyrin derivatives. We describe here a concise convergent synthetic route leading to a symmetric azaporphyrin 7a and its zinc compex 22.