A transition metal complex which is a bis-arylimine pyridine MXn complex, comprising a bis-arylimine pyridine ligand having the formula (I), wherein R1-R5, R7-R9, R12 and R14 are each, independently, hydrogen, optionally substituted hydrocarbyl, an inert functional group, or any two of R1-R3 and R7-R9 vicinal to one another taken together may form a ring, and R6 is hydrogen, optionally substituted hydrocarbyl, an inert functional group, or taken together with R7 or R4 to form a ring, R10 is hydrogen, optionally substituted hydrocarbyl, an inert functional group, or taken together with R9 or R4 to form a ring, R11 is hydrogen, optionally substituted hydrocarbyl, an inert functional group, or taken together with R12 or R5 to form a ring, R15 is hydrogen, optionally substituted hydrocarbyl, an inert functional group, or taken together with R14 or R5 to form a ring, provided that R13 and at least one of R12 and R14 are independently selected from optionally substituted C1-C30 alkyl, optionally substituted C4-C30 alkyloxy, halogen and optionally substituted C5-C20 aryl, or R13 taken together with R12 or R14 form a ring, or R12 taken together with R11 form a ring and R14 taken together with R15 form a ring, and provided that at least one of R12, R13 and R14 is optionally substituted C4-C30 alkyloxy; M is a transition metal atom in particular selected from Ti, V, Cr, Mn, Fe, Co, Ni, Pd, Rh, Ru, Mo, Nb, Zr, Hf, Ta, W, Re, Os, Ir or Pt; n matches the formal oxidation state of the transition metal atom M; and X is halide, optionally substituted hydrocarbyl, alkoxide, amide, or hydride. The transition metal complexes of the present invention, their complexes with non-coordinating anions and catalyst systems containing such complexes have good solubility in non-polar media and chemically inert non-polar solvents especially aromatic hydrocarbon solvents. The catalyst systems can be used for a wide range of (co)oligomerization, polymerization and dimerization reactions. |