[Cp2V(μ-η2:η4-butadiyne)MCp2′] (M=Ti, Zr; Cp′=C5H5, C5H4SiMe3): Heterodimetallic Complexes from a Bis(alkynyl)metallocene and Vanadocene—Unexpected Structure of [Cp2V(μ-η2:η4-butadiyne)Zr(C5H4SiMe3)2] Containing Two Planar-Tetracoordinate Carbon Atoms

Abstract

Titanium–vanadium and zirconium–vanadium complexes are obtained from the reaction between bis(phenylethynyl)titanocene, or -zirconocene, and vanadocene. The X-ray structure analysis of [Cp2V(μ-η2-η4-butadiyne)Zr(C5H4SiMe3)2] (depicted on the right) reveals that the [Cp2V] metallocene moiety is bonded to a butadiene (or butadiyne) framework through the two internal carbon atoms and that the [(C5H4SiMe3)2Zr] moiety is bonded to this unit through the two internal carbon atoms and the two external carbon atoms. Both internal carbon atoms of the butadiene skeleton are planar-tetracoordinate.