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 A(3)-and trans-A(2)B-corroles.