PD(II) AND PT(II) COMPLEXES WITH CHALCOGENIDE DERIVATIZED PHOSPHATHIALIGANDS

The mixed phosphine sulfide/thioether and phosphine selenide/thioether ligands L-1-L-4 react with PdCl2 or PtCl2 in the presence of TIPF6 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 v (P=S) or v(P=Se) for the complexes are to low frequency of free L-1-L- 4, indicating coordination via the sulfide or selenide. P-31{H-1}, Se- 77{H-1} and Pt-195 NMR studies confirm eta(4)-ligation in solution, an d the spectra do not alter significantly upon cooling. Also, the Pt-19 5 NMR chemical shifts indicate that the mixed phosphine sulfide/thioet her donor set results in a very similar electronic environment at Pt(I I) to a homoleptic tetrathioether donor set. delta(Pt-195) for the mix ed phosphine selenide/thioether complexes of Pt(II) occur at slightly lower frequency. The crystal structure of L-3 is also reported. (C) 19 98 Elsevier Science Ltd. All rights reserved.