SYNTHESIS AND CHEMISTRY OF 2-PYRIDYL(PHOSPHINE) COMPLEXES OF PLATINUM(0)

The complexes tetrakis[tri(2-pyridyl)phosphine]platinum(0), 1, and tris[2-(diphenylphosphino)pyridine]platinum(0), 2, are synthesized, and characterized by P-31{H-1} and Pt-195{H-1} NMR spectroscopy. The reactions of 1 and 2 with olefins (ethylene, maleic anhydride, diethyl maleate, and olefinic nitriles) are studied and some square-planar Pt(PR3)2(eta-2-olefin) species isolated (PR3 = the pyridylphosphine). No olefin hydration products are observed on heating the olefin complexes in aqueous solution. Oxidative addition of MeI to 1 and to 2 gives the trans-PtI(Me)(PR3)2 species. However, the trans-Pt(H)Cl(PR3)2 species is isolated only from reaction of 2 with gaseous HCl; the hydride reacts with acrylonitrile to form cis-PtCl(CH2CH2CN)(PR3)2.