Influence of CH3 group of μ-N–C–S ligand on the properties of [Fe2(C4H5N2S)2(NO)4] complex

Bi-nuclear neutral sulfur–nitrosyl iron complex [Fe2(SR)2(NO)4] (I) has been obtained by replacement of thiosulfate ligands in dianion [Fe2(S2O3)2(NO)4]2− by 1-methyl-imidazole-2-yl. From X-ray analysis data, the complex has centrosymmetrical dimeric structure, with the iron atoms being linked via μ-N–C–S bridge. From Mossbauer spectroscopy, isomeric shift δFe is 0.180(1) mm/s and quadrupole splitting ΔEQ is 0.928(2) mm/s at T = 290 K. By comparative studying the mass-spectra in the gaseous phase of solid samples decomposition and kinetics of NO release in 1% aqueous solutions of dimethylsulfoxide, using of the ligand with CH3 substituent in position 1 of imidazole-2-thiol was shown to yield a more stable donor of nitrogen monoxide than earlier obtained analog with imidazole-2-thiol, [Fe2(C3H3N2S)2(NO)4].