Gábor Rangits

NMR investigation of platinum-diphosphine complexes in [BMIM][PF6] ionic liquid

Abstract The formation of platinum–diphosphine complexes of catalytic importance was investigated in [BMIM][PF 6 ] (BMIM=butyl-methyl-imidazolium cation) ionic liquid by NMR for the first time. Both the PtCl(SnCl 3 )(bdpp) and Pt(SnCl 3 ) 2 (bdpp) complexes (where bdpp=2,4-bis(diphenylphosphino)pentane) were identified in the insertion reaction of tin(II)chloride into the PtCl bond of PtCl 2 (bdpp) complex. The addition of PPh 3 to PtCl 2 (bdpp) resulted in the formation of [Pt(bdpp)(PPh 3 )Cl] + complex cation as a minor component, which turned to be a major component in the presence of tin(II)chloride while it forms trichlorostannate counterion. Both types of reactions show high similarity with those obtained in conventional organic solvents . As a serious disadvantage of the use of [BMIM][PF 6 ] as ionic liquid, the partial decomposition of the hexafluorophosphate counterion in the presence of the smallest amount of water (and tin(II)chloride) is also discussed.

The formation of [PtCl(diphosphine-I)(β1-diphosphine-II)]+ species in the N-butyl-N′-methylimidazolium hexafluorophosphate ionic liquid: An NMR study

(Trichlorostannato)diphosphineplatinum(II) complexes of catalytic importance were investigated in the [BMIM][PF6] (BMIM = N-butyl-N′-methylimidazolium ion) ionic liquid by NMR. Formation of mononuclear [PtCl(diphosphine-I)(η1-diphosphine-II)]+ species involving monodentate coordination of one of the two diphosphines as well as dinuclear complexes [Pt2Cl2(diphosphine-I)2(η1,η1-diphosphine-II)]2+ with a bridging bidentate phosphine was observed. Assignment of the structures is based on diagnostic 2 J(P, P) and 1 J(Pt, P) coupling constants obtained from typical second-order AMX 31P NMR spectra.