Pd(II) and Pt(II) complexes with chalcogenide derivatized phosphathia ligands

The mixed phosphine sulfide/thioether and phosphine selenide/thioether ligands L1-L4 react with PdCl2 or PtCl2 in the presence of TlPF6 in MeNO2 solution to give the distorted square planar complexes [Pd(L)](PF6)2 or [Pt(L)](PF6)2 as powdered solids. IR spectroscopy shows ν(PS) or ν(PSe) for the complexes are to low frequency of free L1-L4, indicating coordination via the sulfide or selenide. 31P{1H}, 77Se{1H} and 195Pt NMR studies confirm η4-ligation in solution, and the spectra do not alter significantly upon cooling. Also, the 195Pt NMR chemical shifts indicate that the mixed phosphine sulfide/thioether donor set results in a very similar electronic environment at Pt(II) to a homoleptic tetrathioether donor set. δ(195Pt) for the mixed phosphine selenide/thioether complexes of Pt(II) occur at slightly lower frequency. The crystal structure of L3 is also reported