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Updated: Jul 14, 2025

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
Reaction of a Co(III)-peroxo complex with nitric oxide: putative formation of a peroxynitrite intermediate
Bapan Samanta1, Riya Ghosh1, Rakesh Mazumdar1
1Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India. biplab@iitg.ac.in.
Abstract:
A Co(II) complex, [CoII(L)2(H2O)2](ClO4)2, 1, having a bidentate ligand L [L = bis(3,5-dimethylpyrazolyl)methane] has been synthesized. Complex 1 in acetonitrile solution at -40 °C, in the presence of H2O2 and NEt3, afforded the corresponding Co(III)-peroxo species, [CoIII(L)2(O22-)]+, as the transient intermediate 1a. Thermal instability precluded its isolation and further characterization. The addition of nitric oxide (NO) gas into the freshly prepared [CoIII(L)2(O22-)]+ in acetonitrile at -40 °C resulted in the corresponding Co(II)-nitrato complex, [CoII(L)2(NO3)](ClO4) (2). The reaction is proposed to proceed through a putative Co(II)-peroxynitrite intermediate 1b. It was evidenced by the characteristic phenol ring nitration reaction.
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