Acid-induced conversion of nitrite to nitric oxide at the copper(ii) center: a new catalytic pathway

Abstract

Acid-catalyzed conversion of nitrite to nitric oxide at the copper(ii) center: a new catalytic pathway.

Reduction of nitrite to nitric oxide and generation of reactive chalcogen species by mononuclear Fe(ii) and Zn(ii) complexes of thiolate and selenolate

“…− have been reported in the literature. 38,[51][52][53][54][55][56][57][58][59][60] Chemical reduction of nitrite at first-row transition metal centres involving exogenous reducing agents such as thiols, 61,62 H 2 S, 63 phenols, [64][65][66] enediols, 67,68 VCl 3 69 and phosphines 59 is also available in the literature. In particular, examples of nitrite reduction by model iron(II) compounds include the acid induced nitrite reduction by the complexes [(12TMC)Fe(NO 2 )] 1+ (where 12TMC is 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane), 58 [(Me 2 BPMEN)Cu(NO 2 )] 1+ (where Me 2 BPMEN is N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-1,2-diaminoethane) 60 and [(H 2 BPMEN)Cu(NO 2 )] 1+ (where H 2 BPMEN is N,N′-bis(2-pyridylmethyl)-1,2-diaminoethane); 60 generation of NO upon reduction of [L 2 Cu(nitrite)] 1+ by 4-methoxy-2,6-di-tert-butylphenol (where L = Me 2 PzPy and Me 2 PzQu); 66 Im is a planar, neutral, imine/imidazole, N4-ligand) with thiol or a mixture of thiol and tosylic acid to produce NO; 61 reduction of nitrite to NO by [Fe II (HCTPPH)Br] (where CTPP denotes the trianionic N-confused porphyrin macrocycle) without the presence of a reductant or an oxygen acceptor; 70 reaction of a formally allferrous hexa-iron cluster, ( H L) 2 Fe 6 (where H LH 6 is MeC (CH 2 NHPh-o-NH 2 ) 3 ), with NO 2 − and benzoic acid to produce a hexa-iron hexa-nitrosyl cluster, ( H L) 2 Fe 6 (NO) 6 , via the intermediate, [(HL) 2 Fe 6 (NO 2 ) 6 ] 2− ; 71 reaction of [N(afa Cy ) 3 Fe(OTf )] 1+ (where afa Cy is the amino-azafulvene tautomer of tris(5-cycloiminopyrrol-2-ylmethyl)amine (H 3 [N( pi Cy ) 3 ])) with NO 2 − to generate NO and an Fe(III)-oxo/hydroxide species; 72,73 and the generation of NO and H 2 O upon treatment of [(Bim) 3 Fe(κ 2 -O 2 N)] 1+ (where (Bim) 3 is tris(2-benzimidazolylmeth...…”