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-C₅H₅)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-C₅H₅)₃] in high yield. The n.m.r. data for the new complexes are reported and discussed.