New Titanatranes:  Characterization and Styrene Polymerization Behavior

Abstract

New titanatranes containing cyclopentadienyl ligands were prepared by the reactions of various kinds of trialkanolamines with (C 5 Me 4 R)TiCl 3 (Cp‘ = C 5 Me 4 R) in the presence of triethylamine. The X-ray analyses reveal that they exist in the monomeric form in the solid state and the Ti atom adopts essentially an η 5 bonding posture with the Cp‘ ring and a tetradentate bonding mode with the trialkanolatoamine ligand via a transannular interaction from the bridgehead N atom to Ti. All compounds show very high catalytic activity for the syndiospecific polymerization of styrene in the presence of modified methylaluminoxane (MMAO) cocatalyst.