Thionitrosyl complexes, ruthenium

Thiazyl monomer can be stabihzed by coordination to a metal, and many thionitrosyl complexes with Cr, Mo, Re, Ru, Os, Co, Rh, Ir, and Pt are known. Comparison of the spectroscopic properties and the electronic stmctures of M-NS and M NO complexes indicates that NS is a better a-donor and jr-acceptor ligand than NO. Oxygen transfer from an NO2 to an NS ligand on the same metal center occurs in ruthenium porphyrin complexes. ... 

Trichloro(thionitrosyl)bis(triphenylphosphine)ruthenium(II)was previously prepared by the reaction of trithiazyl trichloride in THF with RuCL xHjO and triphenylphosphine in absolute ethanol. The product crystallizes over a period of several hours, and the yield is very poor. The same complex can be prepared from dichlorotris(triphenylphosphine)ruthenium(II) in CH2CI2 and trithiazyl trichloride in tetrahydrofuran (THF) in a better yield and in less time. 

Trichloro(thionitrosyl)bis(triphenylarsine)ruthenium(II) forms orange-brown glistening plates that do not melt upto 260°C in air. The infrared spectrum of the compound in KBr shows a strong absorption band at 1300cm" assigned to v(NS). The complex is moderately soluble in dichloromethane, chloroform, and benzene but insoluble in alcohol, ether, and hexane. The compound is stable in air for an indefinite period. X-ray diffraction pattern of powdered Ru(NS)Cli(AsPh,), shows it to be isomorphic with Ru(NO)Cl3(PPh3)3. ... 

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