Chemistry of Polynuclear Metal Complexes with Bridging Carbene or Carbyne Ligands. Part 82.' Dimetallic Compounds prepared from the Complexes [MR2(η-C5H5)2](R = Cl or Bun; M = Ti or Zr)

Abstract

The bis(cyclopentadienyl)metal dihalides [MCl2(η-C5H5)2] (M = Ti or Zr) are reduced by magnesium amalgam in tetrahydrofuran in the presence of the alkylidyne-tungsten complexes [W(≡CR)(CO)2(η-C5H5)] (R = C6H4Me-4 or C6H4OMe-2) to afford the dimetal compounds [MW(μ-CR)(μ-σ:η2-CO)(CO)(η-C5H 5)3]. Alternatively, the reagents [M(Bun)2(η-C5H5)2] (M = Ti or Zr), prepared in situ in diethyl ether, react with the complexes [M′(≡CR)(CO)2(η-C5H5)] (M = Ti, M′ = W, R = C6H4Me-4 or C6H4OMe-2; M = Zr, M′ = W, R = Me, C6H4Me-4,C6H4OMe-2, or C6H3Me2-2,6; M′ = Mo, R = C6H4OMe-2) to give the compounds [MM′(μ-CR)(μ-σ:η2-CO)(CO)(η-C 5H5)3] in high yield. The n.m.r. data for the new complexes are reported and discussed.