Titanium(IV) complexes containing mono-cyclopentadienyl and bulky trityloxy mixed ligands: synthesis and polymerization activity

Eight new R1CpTiCl2(OC(C6H4R2)Ph2) complexes were synthesized by the reaction of R1CpTiCl3 with Ph2(R2C6H4)COH (R2C6H4 = phenyl or o‐methyl‐phenyl) in the presence of Et3N in good yield and characterized by 1H NMR, elemental analysis, IR and mass spectrometry. A suitable single crystal of complex 2 (R1: CH3, R2: H) was obtained and the structure determined by X‐ray diffraction. When activated by methylaluminoxane (MAO), all complexes were active for the polymerization of ethylene and styrene. The effect of variation in temperature, catalyst concentration and MAO/catalyst molar ratio was also studied. Complex 5 (R1: n‐C4H9, R2: H) showed a moderate conversion (37.4%) for the polymerization of methyl methacrylate. Copyright © 2005 John Wiley & Sons, Ltd. Eight new Cp′TiCl2(OR) complexes were synthesized and the structure of a suitable single crystal of complex 2 (R1: CH3; R2: H) was determined by X‐ray diffraction. When activated by methylaluminoxane (MAO), all complexes were active for the polymerization of ethylene, styrene and MMA. The effect of variation in temperature, catalyst concentration and MAO/catalyst molar ratio was studied, and the influence of the functional group on the catalyst activity is also discussed.