Reactivity of Dipyridyl Ditellurides with (Diphosphine)Pt0 and 2-Pyridyltellurolates with (Diphosphine)PtCl2 and Isolation of Different Structural Motifs of Platinum(II) Complexes

Oxidative addition reaction of dipyridyl ditellurides to [Pt-2(dppm)(3)] gave two types of complexes, [Pt{2-Te-C5H3(3-R)N}(2)(dppm)] (1) and [Pt{PPh2C(TeC5H3(3-R)N)(2)PPh2}(2)] (2) (R = H or Me), in similar to 6S and similar to 20% yield, respectively. Both these complexes are also formed in the substitution reaction between [PtCl2(dppm)] and NaTeC5H3(3-R)N. Treatment of [Pt(dppe)(2)] with dipyridyl ditellurides yielded an oxidative addition product, [Pt{2-Te-C5H3(3-R)N}(2) (dppe)] (3) (R = H or Me), exclusively. In a substitution reaction of [PtCl2(dppe)] with NaTeC5H3 (3-Me)N a complex of composition Pt{TeC5H3(3-Me)N}(dppe)Cl (4) was formed. The reaction between either [Pt(dPPP)(2)] and Te-2(C5H3(3-Me)N)(2) or [PtCl2(dppp)] and NaTeC5H3(3-R)N afforded a mixture of [Pt{2-Te-C5H3(3-Me)N}(2)(dPPP)] (5) and [Pt3Te2(dpPP)(3)](2+) (6), which were separated by column chromatography. All the complexes were characterized by elemental analyses and NMR (H-1, P-31, Pt-195) spectroscopy. The molecular structures of [Pt{PPh2C(TeC5H4N)(2)PPh2}(2)] and [Pt-2{TeC5H3(3-Me)N}(2)(dppe)(2)][BPK4](2) were established by single-crystal X-ray diffraction analyses. The bonding, charge transfer, and geometry of compounds [Pt{2-Te-C5H3(3-R)N}(2)(dppm)] (1), [Pt{PPh2C(TeC5H3(3-R)N)(2)PPh2}(2)] (2), and [Pt3Te2(dppp)(3)](2+) (6) have been analyzed through relativistic density functional calculations.