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Updated: Jun 15, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
A stable radical within a N-Co-N core
Anirban Bhandari1, Gyeong Min Park1, Heui Beom Lee1
1Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea. yunhochem@snu.ac.kr.
Abstract:
A N-Co-N core is embedded within [Co(CNC)2]2+ (1) supported by two bis(4-methyl-2-(3-methyl-imidazolium)phenyl)amine (CNC) ligands. This species reveals a stable S = 1/2 state and its spin density is significantly delocalized within the N-Co-N core via parallel π-bonding interaction. Interestingly, it displays unusual stability towards O2 and water, proving that the core is well protected. Upon reduction, compound 1 was converted to its reduced diamagnetic species [Co(CNC)2]+ (2) having two amide donors and a low-spin Co(III) ion, which can be oxidized by air to regenerate 1.
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