Ru-Iii(Edta)-Mediated Interaction Of Nitrite And Sulphide: Formation Of An N-Bonded Thionitrous Acid (Hsno) Complex Of Ru-Iii(Edta) In Aqueous Solution

The nitrite anion (NO2-) is an important source of nitric oxide (NO) or nitrosonium cations (NO+). In the present study, we have shown that [Ru-III(edta)(NO+)] (edta(4-) = ethylendiaminetetraacetate) generated via decomposition of [Ru-III(edta)(NO2)](2-) at lower pH (3.5) could react with H2S to form a putative thionitrous acid (HSNO) bound Ru(edta) complex in aqueous solution. The reaction product [Ru-III(edta)(NOSH)](-) was characterized by IR, EPR and ESI-MS spectroscopy. Formation of N-coordinated [Ru-III(edta)(NOSH)](-) was further corroborated by DFT calculations.