Metal‐Assisted Cyclomerization of N‐Confused Dipyrrins into Expanded Norroles

Abstract

Neoconfusion: In contrast to metal ligation by dipyrrin (see scheme, left), N‐confused dipyrrin undergoes cyclomerization with various metal salts to form NCNCNC and NCNCNCNC expanded norroles (see scheme, right), novel isomers of 24 π rosarin and 32 π octaphyrin with C–N linked bipyrrole units with near‐planar conformations in the solid state. They also exhibit paratropic ring‐current effects typical of antiaromatic porphyrinoids.