N-Fused Porphyrin: A Maverick Member of the Porphyrin Family

Abstract

as a Postdoctoral Fellow. In 1992, he started his independent academic carrier at Oita University as an Associate Professor. In 1997, he moved to Kyoto University as an Associate Professor and worked with Prof. Atsuhiro Osuka. In 2002, he was appointed as a Full Professor at Kyushu University. His current research focuses on the synthesis of porphyrin analogues, so-called N-confused porphyrinoids, and the development of NIR dyes with novel function. Motoki Toganoh received his Ph.D. in 2003 from the University of Tokyo under the supervision of Prof. Eiichi Nakamura. In 2000, he studied at Emory University in Prof. Frank E. McDonald's group as a short-term visiting researcher. After receiving his Ph.D., he spent six months as a postdoctoral fellow at Kyoto University in the Prof. Kohei Tamao's group and then joined Prof. Hiroyuki Furuta's group at Kyushu University in 2003 as an Assistant Professor. His current research interests are unique interaction between metal centers and large π-systems.

Iridium Complex of N‐Fused Bilatrienone: Oxidative Cleavage of N‐Fused Porphyrin Induced by Iridium‐Cyclooctadiene Complexation

“…The resulting sp 2 C16−O2 and C15−O1 bonds were typical double bonds with lengths of 1.244(5) and 1.270(5) Å, respectively. In contrast to the sitting atop metal coordination in the previously reported NFP complexes, Ir ‐ 3 displayed in‐plane coordination of the iridium cation to the NNOC core [20,38] . The corresponding σ‐carbon donor site, which originated from the cyclooctene ligand fused to the α‐confused pyrrole ring of NFP, led to the formation of an unusual C( sp 3 )‐Ir bond with a bond length of 2.069(4) Å (Figure S10).…”

“…In this work, we investigated the degradation of N‐fused porphyrin (NFP; 1 ), an asymmetric porphyrin congener derived from 6 through an oxidative internal ring fusion with the adjacent pyrrole (Figure 1c) [20] . The inner fused [5.5.5]‐pentacyclic moiety in the fused analog 1 contributed to the distinct near‐infrared (NIR) optical properties, which were attributed to the distinct 18π aromatic structure [21,22] .…”

NH Tautomerism of N-Confused Porphyrin: Solvent/Substituent Effects and Isomerization Mechanism

“…Then, we discuss model (iv). The pyrrole inversion of NCP is commonly observed in the synthesis of N-fused porphyrin from NCP. − Theoretical study has shown that the activation energy of pyrrole ring rotation in 2a is 25.3 kcal/mol, which is much lower than that of TPP, which is 36.5 kcal/mol (Figure S10). , The inverted arrangement of the confused pyrrole ring has been reported for a NCP dimer, in which two NCP molecules are covalently linked at the inner carbon atoms, and a hydrogen bond is formed between the inner N4-H and N1 of the inverted confused ring .…”

Synthesis of N-fused dithia and dibenzi homoporphyrins

“…N-Fusion in porphyrins and expanded porphyrins has created significant curiosity since their structures, and spectral and coordination properties are quite unique and different from their non-fused congeners. 1–6 Fusion occurs because of intra-molecular bond formation in the inner core of a porphyrinoid skeleton due to dehydrogenation or oxidation. 3 Porphyrinoids with a flexible macrocyclic framework generally show a tendency to undergo intramolecular oxidation to form fused moieties in their macrocyclic framework.…”

“…1–6 Fusion occurs because of intra-molecular bond formation in the inner core of a porphyrinoid skeleton due to dehydrogenation or oxidation. 3 Porphyrinoids with a flexible macrocyclic framework generally show a tendency to undergo intramolecular oxidation to form fused moieties in their macrocyclic framework. 7 Pyrrole/heterocyclic ring inversion is more common in expanded porphyrinoids with more than four pyrrole rings due to their intrinsic flexible nature leading to easier intramolecular fusion in the system such as N-fused pentaphyrin I (Chart 1).…”