Tin(II) Halide Insertion or Halogen Exchange in the Reactions of Dihaloplatinum(II) Complexes with Tin(II) Halide

Reactions of SnCl2 with the complexes cis-[PtCl2(P-2)](P-2 = dppf (1,1'-bis(diphenylphosphino)ferrocene), dppp (1,3-bis(diphenylphosphino)propane = 1,1'-(propane-1,3-diyl)bis[1,1-diphenylphosphine]), dppb (1,4-bis(diphenylphosphino)butane = 1,1'-(butane-1,4-diyl)bis[1,1-diphenylphosphine]), and dpppe (1,5-bis(diphenylphosphino)pentane = 1,1'-(pentane-1,5-diyl)bis[1,1-diphenylphosphine])) resulted in the insertion of SnCl2 into the Pt-Cl bond to afford the cis-[PtCl(SnCl3)(P-2)] complexes. However, the reaction of the complexes cis-[PtCl2(P-2)](P-2 = dppf, dppm (bis(diphenylphosphino)methane = 1,1'-methylenebis[1,1-diphenylphosphine]), dppe(1,2-bis(diphenylphosphino)ethane = 1,1'-(ethane-1,2-diyl)bis[1,1-diphenylphosphine]), dppp, dppb, and dpppe; P = Ph3P and(MeO)(3)P) with SnX2 (X = Br or I) resulted in the halogen exchange to yield the complexes [PtX2(P-2)]. In contrast, treatment of cis-[PtBr2(dppm)] with SnBr2 resulted in the insertion of SnBr2 into the Pt-Br bond to form cis-[Pt(SnBr3)(2)(dppm)], and this product was in equilibrium with the starting complex cis-[PtBr2(dppm)]. Moreover, the reaction of cis-[PtCl2(dppb)] with a mixture SnCl2/SnI2 in a 2 : 1 mol ratio resulted in the formation of cis-[PtI2(dppb)] as a consequence of the selective halogen-exchange reaction. P-31-NMR Data for all complexes are reported, and a correlation between the chemical shifts and the coupling constants was established for mono- and bis(trichlorostannyl)platinum complexes. The effect of the alkane chain length of the ligand and Sn-II halide is described.