Syntheses of titanium(IV) complexes with mono-Cp and Schiff base ligands and their catalytic activities for ethylene polymerization and ethylene/1-hexene copolymerization

The syntheses of two kinds of titanium(IV) complexes with mono-Cp and Schiff base as the mixed ligands are reported. These complexes are synthesized by the reaction of CpTiCl3 with the Schiff base lithium salt, and they are characterized by H-1 NMR, EA, IR, and MS. When activated by excess methylaluminoxane (MAO), all complexes are active for ethylene polymerization and ethylene/1-hexene copolymerization. 1/MAO shows 3 times as active as complex 7 (Cp2TiCl2) to the ethylene/1-hexene copolymerization, and the molecular weight of the copolymer obtained by 1/MAO is almost 2 times that of complex 3 and 5 times that of complex 7. Complex 1 combines the advantages of non-metallocene (complex 3) and metallocene (complex 7) to the ethylene polymerization and ethylene/1-hexene copolymerization.