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Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
Coupling of Nitric Oxide and Release of Nitrous Oxide from Rare-Earth-Dinitrosyliron Complexes
Arun Kumar Bar1, María José Heras Ojea1, Jinkui Tang2
1Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, U.K.
Abstract:
Addition of Lewis acidic [Cp*2M]+ (M = Y, Gd) to the dinitrosyliron complexes (DNICs) [(NacNacAr)Fe(NO)2]- (Ar = mesityl, 2,6-diisopropylphenyl) results in formation of the isonitrosyl-bridged DNICs [(Cp*)2M(μ-ON)2Fe(NacNacAr)]. When Ar = 2,6-diisopropylphenyl, coupling of the NO ligands and release of N2O occur. Two factors contribute to this previously unobserved DNIC reactivity mode. First, the oxophilic rare-earth elements drive the formation of isonitrosyl bonds, forcing the DNIC nitrogen atoms into proximity. Second, the bulky substituents further squeeze the DNIC, which ultimately overcomes the barrier to NO coupling, demonstrating that N2O elimination can occur from a single iron center.
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