Citation: Bingjie Fu, Yue Zhao, Yang Li, Wenfeng Jiang, Wei Bai. Osmacyclopentatrienyl radicals with a delocalized unpaired electron[J]. Chinese Chemical Letters, ;2026, 37(10): 112281. doi: 10.1016/j.cclet.2025.112281 shu

Osmacyclopentatrienyl radicals with a delocalized unpaired electron

Bingjie Fu ^a ,
Yue Zhao ^a ,
Yang Li ^{b, *,} ,
Wenfeng Jiang ^{a, *,} ,
Wei Bai ^{a, *,}

a.
School of Chemistry, Dalian University of Technology, Dalian 116024, China
b.
School of Chemical Engineering, Ocean and Life Sciences, Dalian University of Technology, Panjin 124221, China

chyangli@dlut.edu.cn

jiangwf@dlut.edu.cn

baiwei@dlut.edu.cn

Received Date: 8 October 2025
Revised Date: 2 December 2025
Accepted Date: 12 December 2025
Available Online: 13 December 2025

Figures(6)

Substituted cyclopentadienyl (Cp) radicals, as well as other Cp and fluorenyl-based radicals, exhibit deviations from ideal fivefold D_5h symmetric structures due to Jahn-Teller distortion. The unpaired electron is unequally distributed on the five carbons. Herein, we report the metalla-analogs of Cp radicals from one-electron reduction of antiaromatic osmacyclopentatriene complexes. The novel osmacyclopentatrienyl radicals are nonaromatic, with the single unpaired electron delocalized over the entire five-membered osmacycle. Furthermore, these osmacyclopentatrienyl radicals can be oxidized to regenerate osmacyclopentatrienes and reduced to form osmacyclopentadienes. This discovery provides new insights into radical chemistry and organometallic chemistry.
- Antiaromaticity,
- Osmacyclopentatriene,
- Osmacyclopentadiene,
- Radical,
- Redox reaction
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