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Published on: July 28, 2022
Reversible Ring Oxidation of 48π Planar Nonaphyrins to Open Shell 46π Dications
Tullimilli Y Gopalakrishna1,2, Ashokkumar Basavarajappa1, Hosahalli S Udaya1
1Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, 411008, Maharashtra, India.
Abstract:
We report the synthesis and characterization of 48π nonaphyrins, a novel class of planar expanded porphyrinoids exhibiting distinct electronic properties compared to their 32π congeners. Single-crystal X-ray diffraction studies revealed heterocycle dependent structural topology for these macrocycles. All the isolated nonaphyrins display weak paratropic ring current effects and undergo reversible two-electron ring oxidation to yield the respective 46π dicationic diradicaloid species. The formation of oxidized diradicaloid species was confirmed by ESR spectroscopy, spectro-electrochemical measurements and further supported by quantum chemical calculations.
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