Synthesis of nonbridged (anilide)(cyclopentadienyl)titanium(IV) complexes of the type Cp′TiCl2[N(2,6-Me2C6H3)(R)] and their use in catalysis for olefin polymerization

(Anilide)(cyclopentadienyl)titanium(IV) complexes of the type Cp'TiCl2[N(2,6-Me2C6H3)-(R)] (8a-d: Cp'= C5Me5 (Cp*), 1,3-Me2C5H3, Cp; R = SiMe3, (SiBuMe2)-Bu-t) have been prepared by the reaction of Cp'TiCl3 with the corresponding lithium anilide in toluene. The structure of (1,3-Me2C5H3)TiCl2[N(2,6-Me2C6H3)(SiMe3)] (8b) has been determined by X-ray crystallography. These complexes exhibited high catalytic activities for ethylene polymerization in the presence of methylaluminoxane (MAO); especially Cp*TiCl2[N(2,6-Me2C6H3)(SiMe3)] (8a) exhibited the highest catalytic activity (1080 kg of PEA/((mol of Ti) h)) ethylene 6 atm at 25 degreesC), whereas the analogous zirconium complex Cp*ZrCl2 [N(2,6-Me2C6H3)(SiMe3)] (9a) showed a lower activity (637 kg of PEA((mol of Ti h)) under the same conditions. The activity by Cp'TiCl2[N(2,6-Me2C6H3)(SiMe3)] for the ethylene polymerization increased in the order Cp* > 1,3-Me2C5H3, Cp. The molecular weight for the resultant polyethylene depended upon the cyclopentadienyl fragment used. The low catalytic activity was observed for propylene polymerizations by 8a; the resultant polymer was atactic and possessed high molecular weight with narrow polydispersity.