No abstract

Reaction of [PtCl2(SMe2)2] with Et2PCH2PEt2 (depm) or z'-Pr2PCH2P-z'-Pr2 (dippm) gave mononuclear [PtCl2(depm)] or [PtCl2(dippm)]. In contrast, Z-BuHPCH2PH-Z-Bu (dtbpm) gave the binuclear cis-[Pt2Cl4(M-dtbpm)2] and Me2PCH2PMe2 (dmpm)gave insoluble [(PtCl2(dmpm))"], which, on the basis of IR and MS data, is thought to be cis-[Pt2Cl4(u-dmpm)2]. The structure of [Pt2Cl4(M-dtbpm)2] was established by an X-ray analysis of crystals of its methanol solvate. The crystals are monoclinic, space group P2,/c, with two centrosymmetric molecules of the binuclear complex and four molecules of methanol of solvation in a unit cell of dimensions a = 8.841 (1) Á, b = 9.708 (1) Á, c = 19.841 (3) Á, and ß = 98.23 (2)°. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations to R = 0.059 for 3525 observed reflections. The Pt atom has distorted square-planar geometry with cis Pt-P distances of 2.228 (2) and 2.229 (2) Á and cis Pt-Cl distances of 2.344 (2) and 2.360 (3) A. The eight-membered ring (PtP2C)2 has a slightly deformed chair conformation.

No abstract

Reaction of [P^Me^-dmpm^], dmpm = Me2PCH2PMe2, with halogens gave the bridged Pt(IV)-Pt(II) complexes [Me3Pt(^-X)(^-dmpm)2PtMe]X, 2a-c, X = I, Br, and Cl, respectively, and, when X = I, further reaction with I2 gave [ ß3 (µ-) (g-dmpm)2PtMe]I3 and [ ß3 (µ-)(µ-<)2 ] 3. The complexes were

Two n e w structural types of binuclear platinum(0) complexes of formulae [Pt2(p-R2PCH2PR2)3(PPh3)], (2), and(3), have been characterized by n.m.r. spectroscopy and, for (2; R = Me), b y X-ray crystallography; steric requirements of R determine the preferred structures and complexes (2; R = M e or Et) are shown to contain both 3-co-ordinate and 4-co-ordinate platinum(0) centres.