Titanium and zirconium ketimide complexes: synthesis and ethylene polymerisation catalysis

New ketimide titanium compounds, Ti(NCtBu2)3X (X = Cl, Cp, Ind) and Ti(NCtBu2)4 and the zirconium complex CpZr(NCtBu2)2Cl are described. When activated by MAO, all compounds are ethylene polymerisation catalysts. The most active catalyst is CpZr(NCtBu2)2Cl, with an activity of 2.7 × 105 kg/(molZr [E] h). Titanium complexes are less active by about two orders of magnitude.