96453-00-8Relevant articles and documents
Activation of vinylidenebis(diphenylphosphine) through metal complexation
Schmidbaur, Hubert,Herr, Rudolf,Müller, Gerhard,Riede, Jürgen
, p. 1208 - 1213 (2008/10/08)
Vinylidenebis(diphenylphosphine) (vdpp) was found to give an insoluble 1:2 complex, (vdpp)·(AuCl)2 (1), but a soluble 1:1 complex, (vdpp·AuCl)2 (2), when treated with (CO)AuCl in the appropriate molar ratio. The crystal structure determination of (vdpp·AuCl)2·CHCl3 revealed a dimer with a centrosymmetric eight-membered ring skeleton composed of two P,P-bridging vdpp ligands, and trigonally coordinated Au(I) centers, with the two AuP2Cl planes parallel to each other. The vinylidene groups are not engaged in metal bonding but have become strongly activated through the vdpp-metal coordination. Methanol is added at 20°C to give the AuCl complex of 1,1-bis(diphenylphosphino)-2-methoxyethane (6). This addition is reversible, and the CH3OH is lost quantitatively at 150°C, with recovery of 2. 1:1 complexes were also prepared from CuCl, AgCl, AgOCOCH3, and AgBF4 (3, 4a-c), but the vdpp ligands in none of these products is sufficiently activated to give similar addition reactions. Elemental analyses, osmometric molecular mass data, and 1H, 13C, and 31P NMR, IR, and mass spectra were used for a preliminary characterization of the compounds. The X-ray data for 2 are as follows: (C26H22AuClP2)2·CHCl 3, a = 9.920 (2) A?, b = 11.545 (2) A?, c = 12.272 (2) A?, α = 90.40 (1)°, β = 88.25 (2)°, γ = 109.17 (1)°, dcalcd = 1.723 g cm-3 for Z = 1, space group P1; 4339 observed reflections, R = 0.033. Rw = 0.042.
