Treatment of the N-P ligand (ArN)-N-P(SiMe3)(2) with TiCl4 affords the imido-bridged binuclear titanium complex [TiCl2(THF)(mu-NArP)](2) (Ar-P = m-C6H4PR2) which reacts with Ni(0) or Pd(II) to give heterotrinuclear compounds, while activation with methylaluminoxane generates a new type of imido-based ethene polymerisation catalyst that is tolerant of - PR2 functional groups.