Regioselective synthesis of 2-nitro-5,10,15,20-tetra(2-methoxylphenyl) porphyrin and its Atropisomerism

In the process of synthesizing β-nitro-5,10,15,20-tetra aryl porphyrinato copper(II) and nickel(II) by regioselective nitration,atropisomerism was found in meso-tetra(2-methoxylphenyl)-porphyrin.The nuclear magnetic spectrometry analysis showed that,unlike the 5,10,15,20-tetra(hydroxyphenyl)-porphyrin,atropisomer happens in the 5,10,15,20-tetra(2-methoxyphenyl) porphyrin,because o-methoxyl hinder rotation of σ-bond between the meso-phenyl and porphyrin,the possibility structure of atropisomer was discussed through minimize energy calculation by Chemdraw 3D Ultra software.