Cp[Tm Me]ZrCl 2, the first tris(2-mercapto-1- methylimidazolyl)hydroborato complex of zirconium, is obtained by reaction of CpZrCl 3 with [Tm Me]K. The molecular structure of Cp[Tm Me]ZrCl 2 has been determined by X-ray diffraction, and the geometry closely resembles the bent-metallocene motif of Cp 2ZrCl 2. An important distinction, however, is that Cp[Tm Me]-ZrCl 2 is chiral, with C 1 symmetry. The chirality of Cp[Tm Me]-ZrCl 2 is a consequence of the fact that the [Tm Me] ligand exhibits a propeller-like twist such that it has local C 3 symmetry and is therefore devoid of a mirror plane. Variable-temperature 1H NMR studies demonstrate that enantiomer interconversion does not occur on the NMR time scale. In combination with methylalumoxane, Cp[Tm Me]ZrCl 2 produces an active catalyst for ethylene polymerization.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry