Benzonorcorrole NiII Complexes: Enhancement of Paratropic Ring Current and Singlet Diradical Character by Benzo-Fusion

Takuya Yoshida; Kohtaro Takahashi; Yuki Ide; Ryohei Kishi; Jun-Ya Fujiyoshi; Sangsu Lee; Yuya Hiraoka; Dongho Kim; Masayoshi Nakano; Takahisa Ikeue; Hiroko Yamada; Hiroshi Shinokubo

doi:10.1002/anie.201712961

Benzonorcorrole Ni^II Complexes: Enhancement of Paratropic Ring Current and Singlet Diradical Character by Benzo-Fusion

Angew Chem Int Ed Engl. 2018 Feb 19;57(8):2209-2213. doi: 10.1002/anie.201712961. Epub 2018 Jan 24.

Authors

Affiliations

¹ Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan.
² Graduate School of Material Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara, 630-0192, Japan.
³ Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue, 690-8540, Japan.
⁴ Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, 560-8531, Japan.
⁵ Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul, 03722, Korea.

PMID: 29327805
DOI: 10.1002/anie.201712961

Abstract

Fused benzene rings to antiaromatic compounds generally improve their stability but attenuate their antiaromaticity. The opposite case is now reported. Ni^II benzonorcorroles were synthesized and the effect of benzo-fusion on the antiaromaticity was elucidated. The benzo-fusion resulted in significant decrease of the HOMO-LUMO gaps and enhancement of the paratropic ring current effect. Furthermore, the introduction of the benzo groups induced singlet diradical character in the antiaromatic porphyrinoid.

Keywords: antiaromaticity; diradicals; porphyrinoid; ring current.

Publication types

Research Support, Non-U.S. Gov't