Platinum(II) complexes with dithiolates and phosphinites as ligands: crystal structure of [Pt{S 2CO}{P(OMe)Ph 2} 2

Abstract

Reaction of the complex [PtCl{P(O)Ph 2}{P(OH)Ph 2} 2] with silver or thallium derivatives of dithiolate ligands led to neutral complexes of general formula [Pt{S-S}{P(O)Ph 2}{P(OH)Ph 2}], where { SS} − = { S 2CNEt 2} − { S 2P(OEt) 2} − ( 2) and { S 2COEt } − ( 3) . Complexes 2 and 3 reacted with an excess of NaI in acetone solution by dealkylation of the coordinated dithiolate ligand and formation of the compounds [Pt{S 2P(O)(OEt)}{P(O)Ph 2}{P(OH)Ph 2}]Na ( 4) and [Pt{S 2CO}{P(O)Ph 2}{P(OH)P Na ( 5), respectively. The corresponding tetraphenylphosphonium derivatives ( 6, 7) were prepared by a metathetical reaction of these complexes with Ph 4PBr in acetone solution. Related dithiolate complexes were obtained by reaction of the complex [Pt{S-S} 2] with P(OMe)Ph 2 in molar ratio 1 : 2. Thus, the reaction of [Pt{S 2COEt} 2] in dichloromethane solution at room temperature gave [Pt{S 2COEt}{P(OMe)Ph 2} 2]Cl ( 8). This complex reacted with NaI in acetone to form the neutral compound [Pt{S 2CO}{P(OMe)Ph 2} 2] ( 9). When the reaction was carried out in dichloromethane at reflux temperature using [Pt{S 2P(OEt) 2} 2] as starting material, the neutral compound [Pt{S 2P(O)(OEt)} {P(OMe)Ph 2} 2] ( 10) was obtained. The crystal structure of the complex 9 has been determined by X-ray diffraction. The neutral complex shows a nearly square-planar coordination of the metal and a planar dithiocarbonate ligand.