Reaction of a copper(II)-nitrosyl complex with hydrogen peroxide: phenol ring nitration through a putative peroxynitrite intermediate.
Copper(II) complex, 1, with the histidine-derived ligand L (L = methyl 2-(2-hydroxybenzylamino)-3-(1H-imidazol-5-yl)propanoate) has been synthesized and characterized. Single-crystal structure determination reveals a diphenolato-bridged dicopper(II) core in 1. Addition of (•)NO to an acetonitrile solution of 1 affords the corresponding mononuclear copper(II)-nitrosyl complex, 2. In the presence of H2O2, 2 results in formation of the corresponding copper(I)-peroxynitrite. Formation of peroxynitrite ((-)OONO) intermediate is evident from its characteristic phenol ring nitration reaction which resembles the tyrosine nitration in biological systems. Further, isolation of nitrate (NO3(-)) as the decomposition product from 2 at room temperature also supports the involvement of (-)OONO intermediate.
Department of Chemistry, Indian Institute of Technology , Guwahati, Assam 781039, India.
Apurba
A
Kalita
Ramesh C
RC
Deka
Biplab
B
Mondal
D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006861:Hydrogen Peroxide / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D009566:Nitrates / Q000737:chemistry; D009589:Nitrogen Oxides / Q000737:chemistry*; D030421:Peroxynitrous Acid / Q000737:chemistry*; D019800:Phenol / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared
D056831:Coordination Complexes; D008024:Ligands; D009566:Nitrates; D009589:Nitrogen Oxides; D030421:Peroxynitrous Acid; D019800:Phenol; D003300:Copper; D006861:Hydrogen Peroxide; C087991:nitrosyl chloride