A Triply Linked Porphyrin-Norcorrole Hybrid with Singlet Diradical Character

Kaisheng Wang; Satoru Ito; Shuang Ren; Daiki Shimizu; Norihito Fukui; Ryohei Kishi; Qiang Liu; Atsuhiro Osuka; Jianxin Song; Hiroshi Shinokubo

doi:10.1002/anie.202401233

A Triply Linked Porphyrin-Norcorrole Hybrid with Singlet Diradical Character

Angew Chem Int Ed Engl. 2024 Apr 15;63(16):e202401233. doi: 10.1002/anie.202401233. Epub 2024 Feb 9.

Authors

Kaisheng Wang¹, Satoru Ito¹, Shuang Ren², Daiki Shimizu³, Norihito Fukui^{1

4}, Ryohei Kishi⁵, Qiang Liu², Atsuhiro Osuka⁶, Jianxin Song⁶, Hiroshi Shinokubo¹

Affiliations

¹ Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan.
² College of Chemistry and Chemical Engineering, Advanced Catalytic Engineering Research Center of the Ministry of Education, Hunan University, Changsha, 410082, China.
³ Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.
⁴ PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012, Japan.
⁵ Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.
⁶ Key Laboratory of Chemical Biology and Traditional Chinese Medicine, Ministry of Educational of China, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, 410081, China.

PMID: 38251909
DOI: 10.1002/anie.202401233

Abstract

Norcorrole Ni(II) complexes have recently received considerable attention because they are readily accessible antiaromatic molecules. Their high stability under ambient conditions and ease of synthesis have enabled the exploration of the intrinsic properties of antiaromatic molecules. Here, we report the synthesis and properties of meso-meso singly linked porphyrin-norcorrole hybrids and a triply linked porphyrin-norcorrole hybrid. The singly linked and triply linked porphyrin-norcorrole hybrids were fully characterized, including an X-ray structural analysis. Due to their orthogonal conformation, the singly linked hybrids maintain the individual electronic properties of their porphyrin and norcorrole subunits, while the triply linked hybrid shows a significantly smaller electrochemical HOMO-LUMO gap (0.45 eV) than that of Ni(II) dimesitylnorcorrole (1.08 eV). Furthermore, the triply linked hybrid exhibits singlet diradical characteristics, as confirmed by VT NMR, ESR, and SQUID experiments.

Keywords: aromaticity; diradicals; fused hybrids; norcorroles; porphyrinoids.

Abstract

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