Five-coordinate nickel(II) xanthate derivatives with triphos. Crystal structure of tris(O-cyclohexyldithiocarbonato)nickelate(II) of bis(2-diphenylphosphinoethyl)phenylphosphine-O- cyclohexyldithiocarbonatonickel(II)

Article abstract of DOI:10.1016/0277-5387(95)00358-4

Five-coordinate complexes, [Ni(S₂COR)(TRIPHOS)]X (R = cyclo-C₆H₁₁, X = Cl, PF₆, [Ni(S₂COC₆H₁₁)₃]; R = Et, X = PF₆. [Ni(S₂COEt)₃]), have been obtained by the reaction of O-alkyldithiocarbonato complexes. [Ni(S₂COR)₂], with bis(2-diphenylphosphinoethyl)phenylphosphine (TRIPHOS). The structure of [Ni(S₂COC₆H₁₁) (TRIPHOS)][Ni(S₂COC₆H₁₁)₃] was determined by X-ray crystallography. The compound contains a five-coordinate cation and a hexa-coordinate anion. The geometry about the nickel atom in the [Ni(S₂COC₆H₁₁)(TRIPHOS)]⁺ is distorted trigonal bipyramidal with the axial positions occupied by one sulfur atom of the bidentate O-cyclohexyldithiocarbonate and the central phosphorus atom of the TRIPHOS. In the [Ni(S₂COC₆H₁₁)₃] anion, the nickel atom is bonded to six sulfur atoms of three O-cyclohexyldithiocarbonate ligands. Formation of the dithiocarbonato complexes in the reactions of [Ni(S₂COEt)₂] with TRIPHOS has also been observed.