Three Redox States of Nitrosyl: NO+, NO• and NO–/HNO Interconvert Reversibly on the Same Pentacyanoferrate(II) Platform

MONTENEGRO, A.C.; AMOREBIETA, V.T.; SLEP, L.D.; MARTÍN, D.F.; RONCAROLI, F.; MURGIDA, D.H.; BARI, S.E.; OLABE, J.A.

Angewandte Chemie

WILEY-V C H VERLAG GMBH

Año: 2009 vol. 48 p. 4213 - 4216

1433-7851

One-electron redox changes of bound nitrosyl species are at the heart of the enzymatic processes involving reversible conversions of NO2_ into NH3, which occur either in bacterial processes in soils or in the biosynthesis/degradation events of nitrogen monoxide (NO) in the biological fluids of mammals.We provide the first pKa value for a bound HNO/NO equilibrium under biologically relevant conditions. The decompositions of [FeII(CN)5(HNO)]3_ and [FeII(CN)5(NO)]4_ are different under our reaction conditions: the first generates [FeII(CN)6]4_ and N2O, whereas the conjugate base behaves as a strong reductant, forming [FeII(CN)5(NO)]3_.