Selective Synthesis of Tripyrranes, Tetrapyrranes, and Corroles

A new, catalytic, and general methodology was developed for the direct synthesis of unsymmetrical AB‐type tripyrranes by reaction of dipyrromethanesulfonamides with pyrrole. Key structure dipyrromethanesulfonamides were synthesized by the addition of meso‐substituted dipyrromethanes to Cu(OTf)2‐activated tosylimines. The introduced method enables selective preparation of tetrapyrranes in high yields by tuning the conditions of the addition reaction. The oxidation of tetrapyrranes by 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone afforded only corresponding A3‐ and trans‐A2B‐corroles. A new synthetic strategy has been developed for the selective synthesis of unsymmetrical tripyrranes, tetrapyrranes, and corroles by using dipyrromethanesulfonamides as key intermediates.