We present the synthesis, characterization, X-ray molecular structure, and catalytic activity of a [(HOEt)Ti(μ-OEt)OEt(Cl)2]2 (1) dimeric complex. Complex 1 was found to undergo, in solution, a succession of fluxional processes involving the rotation of the ligands, rapid exchange between the anionic ethoxide ligands, and exchange of the hydroxylic hydrogen. The complex, when activated by methylalumoxane (MAO), undergoes an abstraction of the ligands through a heterobimetallic intermediate with ethoxide bridges between the aluminum and titanium atoms. We propose that this intermediate is the active species in the polymerization of α-olefins. The complex displays unexpectedly a single site behavior in contradiction to other titanium alkoxide complexes. The resulting polymers were found to show elastomeric properties with intermediate tacticities.
|Number of pages||10|
|State||Published - 24 Jul 2007|