Novel Gold(I) and Silver(I) Complexes of Phosphorus-1,1,-dithiolates and Molecular Structure of [O,O'-(Bornyl)2PS2]H3NC(CH3)3

Chem Cent J. 2013 May 20;7(1):89. doi: 10.1186/1752-153X-7-89.

Abstract

Background: The novel chiral phosphorus-1,1-dithiolates [4-CH3OC6H4P(S)(OR)S]-[H3NC(CH3)3]+ were synthesized by the reaction of [RPS2)]2 (R = 4-MeOC6H4) or P2S5 and the respective alcohol ROH (R = myrtanyl, 2-naphthylethyl, myrtenyl, borneol) in toluene. The reaction of phosphorus-1,1-dithiolates 1-4 and Au(tht)Cl, AuClPPh3 or AgNO3 and PPh3 gave rise to gold(I)- and silver(I)-complexes in THF. All compounds have been characterised by elemental analyses, IR, NMR (1H-, 13C- and 31P-) spectroscopy as well as MS measurements. Optical rotation values confirmed the chirality of the compounds. The Compound 4 has been characterized structurally by X-ray crystallography.

Results: Phosphorus-1,1,-dithiolate compounds were formed as liquids and were treated with suitable amine in order to convert them to their salts 1-4 . They have been successfully characterized spectroscopically (IR, 1H, 13C, 31P NMR) as well as mass spectra. The compound 4 has been also structurally by X-ray crystallography. The compound 4 crystallizes in the orthorhombic space group P2(1)2(1)2(1) with Z = 4. Compounds containing phosphorus and sulfur donor atoms are excellent ligands due to offering many metal complexes especially group 11-12 metals. The synthesis of gold(I) and silver(I) complexes with chiral phosphorus-1,1,-dithiolate and triphenylphosphine have been described and investigated.

Conclusions: In the present work, we report the synthesis, charactreization of the chiral phosphorus-1,1-dithiolate ligands and preparing the gold(I) and silver(I) phosphorus-1,1-dithiolate or S-donor with phosphine complexes. The molecular structure of the Compound 4 was determined by X-ray diffraction. Due to an easy synthesis method of phosphorus-1,1-dithiolate compounds and a good complexion reagent, it is possible the improvement of the collecting metallic gold or silver from the minerals. When the more ionic salt of phosphorus-1,1-dithiolate compounds were prepared in this way, the water can be used as a cheap solvent. As a result, it can be an alternatively method for the collecting metallic gold or silver from the minerals in future.