Recent development of a porphyrin mutant - N-confused porphyrin

Unusual α and β' linkage of the pyrrole rings (confusion) in porphyrinoids affords a new family of porphyrin analogs having unique physical properties, reactivity and metal-coordination chemistry. Since the finding of N-confused porphyrin (NCP), an isomer of porphyrin, in 1994, various confused porphyrinoids and their metal complexes, including multiply N-confused, hetero-atom substituted, and ring expanded ones, have been synthesized, successively. Confused porphyrinoids reveal a lot of interesting properties, such as NH tautomerism, inner- and outer-metal coordination, organometallics nature, multiple redox system, extended aromatic π-system, etc. In this article, recent development of the confused porphyrinoids is summarized.