LAUSR

The reduction of nitrite to nitric oxide (NO) is a crucial step in the nitrogen cycle, catalyzed by nitrite reductase in nature, and its efficient catalysis is of great interest. This study reports the achievement of a reduction cycle that releases NO from nitrite using a dinuclear ruthenium complex (NO2 – + 2H+ + e– → NO + H2O). Irradiation or thermolysis of a nitrite-bridged complex, [(TpRu)2(μ-Cl)(μ-NO2)(μ-pz)] (1) (Tp = HB(pyrazol-1-yl)3), resulted in the formation of an oxido-bridged complex, [(TpRu)2(μ-Cl)(μ-O)(μ-pz)] (2), and the release of NO. The reaction mechanism from 1 to 2 was investigated through theoretical calculations. To complete the reduction cycle, complex 1 was reproduced from complex 2 using two protons and one electron in the presence of a nitrite salt. This study demonstrated the successful mimicking of the function of nitrite reductase using a dinuclear ruthenium complex.