Macrocyclic Transformations from Norrole to Isonorrole and an N‐Confused Corrole with a Fused Hexacyclic Ring System Triggered by a Pyrrole Substituent

Abstract

Three kinds of fused porphyrinoids, L2-L4, possessing different types of corrole-based frameworks were synthesized from a pyrrole-substituted corrole isomer (norrole L1). Oxidation of L1 afforded a unique N-Cmeso -fused pyrrolyl isonorrole L2, involving the fusion of an auxiliary pyrrolic NH moiety with a meso-sp(3) -hybridized carbon atom. Subsequently, L2 underwent macrocycle transformations to give singly and doubly N-CAr -fused N-confused corroles, L3 and L4, respectively. L3 and L4 contain fused [5.7.6.5]-tetra- and [5.6.7.7.6.5]-hexacyclic structures, respectively, prepared through lateral annulation. These skeletal transformation reactions from norrole to its isomer isonorrole and finally to N-confused corrole indicate that multiply fused porphyrinoids could be readily synthesized from pyrrole-appended confused porphyrinoids.

Three‐Stage Aromaticity Switching in Boron(III) and Phosphorus(V) N‐Fused p‐Benziporphyrin

“…The three aromatic states can be interconverted one another using diphyrin(11.1) π‐delocalization triggered by a simple initiator. These original macrocycles belong to the innumerous class of contracted carbaporphyrinoids …”

Chiral Interlocked Corrole Dimers Directly Linked at Inner Carbon Atoms of Confused Pyrrole Rings

“…Here, we have extended this approach towards the facile synthesis of peculiar chiral corrole dimers. The peripheral bulky multiple N‐fused ring units should restrict the rotation of the corrole plane of the dimers ( Cu‐L2D and Cu‐L3D ) [9] . On the basis of this design principle, we succeeded in the structural characterization and elucidation of their chiroptical properties.…”

Rapid one-pot synthesis of pyrrole-appended isocorroles

“…15,16 Here we report that meso-pyrrole-appended isocorroles may be obtained in reasonable yields via brief, roomtemperature oxidative coupling of a free-base meso-triarylcorrole and pyrrole (Scheme 1). 17,18,19 Both 5-and 10-isocorroles were obtained, with the former predominating. Unambiguous proof of structure came from two single-crystal X-ray diffraction analyses, one for a free-base 5isocorrole and the other for a Cu(II) 10-isocorrole.…”