On a ruthenium nitrosyl and monocoordinated biphosphine monoxide complex: Synthesis, characterization and X-ray structure of

The reaction product of fac-[RuCl3(NO)(dppm)], dppm = bis(diphenylphosphino)methane with the 2-mercaptopyridine ligand (pyS) in methanol, in the presence of triethylamine, is the nitrosyl derivative [Ru(pyS)2(NO)(dppmO-P)]PF6 (1). In this reaction the ‘pyS’ ligand displaces one of the phosphorus atoms of the dppm moiety and this dangling phosphorus is oxidized in the experimental conditions generating a mono–hapto dppmO. The X-ray crystal structure of the complex image (2) shows sulfur atoms mutually trans and NO and P ligands trans to the pyridinic nitrogens. The νNO band in the IR spectrum is at 1882 cm−1 and in the cyclic voltammogram two processes at −0.45 and −1.15 V (vs Ag/AgCl) are observed indicating a nitrosonium character for the coordinated NO.