Selective synthesis of 5-aryl-10-(nitromethyl) substituted 15-azatripyrrane, 15-oxatripyrrane and 15-thiatripyrrane: access to nitromethyl functionalized A(3)B-porphyrins

A chemical strategy toward the selective synthesis of unsymmetrical tripyrranes was developed for the formation of meso-aryl and -nitromethyl substituted A(3)B porphyrins. The iodine catalyzed addition of meso-substituted dipyrromethanes to nitrovinylarenes to generate unsymmetrical 5-aryl-10-(nitromethyl) substituted 15-azatripyrranes, 15-oxatripyrranes and 15-thiatripyrrane under mild conditions has been investigated. The multicomponent reactions of 15-azatripyrranes provided the construction of meso-aryl and -nitromethyl substituted A(3)B-porphyrins. To the best of our knowledge, the first examples of 5-aryl-10-(nitromethyl) substituted 15-azatripyrranes, 15-oxatripyrranes and 15-thiatripyrrane, and 5-(nitromethyl)-10,15,20-tris(aryl)porphyrins are introduced in this study.