Pyridine‐ and 3‐/6‐Methylpyridine‐2‐tellurolate Complexes of Palladium( II ) and Platinum( II )

The reaction of py2Te2 or (3‐MeC5H3N)2Te2 with Na2PdCl4 in methanol yields an insoluble brown complex, [PdCl(TeNC5H3R)]n (R = H or Me). Several reactions of pyTe−, (3‐MeC5H3N)Te−, or (6‐MeC5H3N)Te− with various palladium(II) and platinum(II) complexes have been carried out. Complexes of the types [MCl(Te−N)(PR3)], [Pt(Te−N)2(dppe)], [Pt(Te−N)2(PPh3)2], and [Pt2(μ‐Te−N)2(dppe)2][BPh4]2 [M = Pd or Pt; Te−N = pyTe, (3‐ or 6‐MeC5H3N)Te] have been prepared and characterized by elemental analyses, UV/Vis, IR, and NMR (1H, 31P, 195Pt) spectroscopy. The complexes [MCl(Te−N)(PR3)] show irreversible oxidation and reduction by CV in DMF. The molecular structure of [PdCl{Te(3‐MeC5H3N)}(PPh3)] (2c) has been established by single‐crystal X‐ray diffraction analysis. The palladium atom is bound to the chelating 3‐methylpyridinetellurolate ligand, a chlorine atom and a PPh3 ligand. The pyrolysis of [PdCl{Te(3‐MeC5H3N)}(PR3)] (PR3 = PEt3 or PPh3) at 340 °C yields PdTe. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)