Ruthenium nitrosyl complexes with bidentate heterocycles: synthesis and their transformations in solution

Abstract

A series of novel complexes with the general formula [RuNO(NH₃)₂(L)(NO₃)]²⁺, where L is a bidentate ligand (bpym, bpy, or phen), were synthesized and characterized. trans-(NO, NO₃) and cis-(NO, NO₃) isomers were identified in the solid state (SCXRD) and in DMSO solution (¹H NMR and IR spectroscopy). Their photochemical activity in DMSO was quantified under 450 nm irradiation using a flow-through system, allowing simultaneous IR and UV-Vis spectral monitoring. Quantum yields for photoinduced release of NO were determined to be 4.0 ± 0.8% for [RuNO(NH₃)₂(bpym)(NO₃)](NO₃)₂ (1), 7.3 ± 0.2% for [RuNO(NH₃)₂(bpy)(NO₃)](NO₃)(PF₆) (2) and 3.1 ± 0.1% for [RuNO(NH₃)₂(phen)(NO₃)](NO₃)₂ (3).