Preparation of polymerisation catalysts

Process for producing a transition metal complex of the formula

• wherein M is Fe[II], Fe[III], Co[I], Co[II], Co[III], Mn[I], Mn[II], Mn[III], Mn[IV], Ru[II], Ru[III] or Ru[IV];
• X is halide, sulphate, nitrate, thiolate, thiocarboxylate, BF−4, PF−6, triflate, tosylate, hydride, hydrocarbyloxide or carboxylate covalently or tonically bonded to the transition metal M;
• T is the oxidation state of the transition metal M and b is the valency of the atom or group X;
• R1, R2, R3, R4, and R6 are independently selected from hydrogen, halogen, or hydrocarbyl;
• and when any two or more of R1-R4 and R6 are hydrocarbyl, said two or more can be linked to form one or more cyclic substituents;
• and
• R5 and R7 are selected from either the rings P and Q respectively,
• wherein R19 to R28 are independently selected from hydrogen, halogen or hydrocarbyl, and when any two or more thereof are hydrocarbyl, said two or more can be linked to form one or more cyclic substituents;
• with the proviso that at least one of R19, R20, R21 and R22 is hydrocarbyl when neither of the ring systems P and Q forms part of a polyaromatic fused-ring system;
• or —NR29R30 and —NR31R32 respectively, wherein R29 to R32 are independently selected from hydrogen, or hydrocarbyl;
• and when any two or more thereof are hydrocarbyl, said two or more can be linked to form one or more cyclic substituents;
• comprising reacting together in a single stage reaction components comprising (1) precursors capable of combining to form Ligand B directly
• and (2) a compound of the formula MM-(T/b)X.