Abstract: A catalyst precursor composition comprising a) a source of chromium, molybdenum or tungsten; b) a first ligand having the general formula (I); (R1)(R2)P—X—P(R3)(R4) ??(I) wherein X is a bivalent organic bridging group; R1 and R3 are independently selected from, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl and substituted heterohydrocarbyl groups, with the proviso that when R1 and R3 are aromatic groups they do not contain a polar substituent at any of the ortho-positions; R2 and R4 are independently selected from optionally substituted aromatic groups, each R2 and R4 bearing a polar substituent on at least one of the ortho-positions; and c) a second ligand having the general formula (II); (R1?)(R2?)P—X?—P(R3?)(R4?) ??(II) wherein X? is a bridging group of the formula —N(R5?)—, wherein R5? is selected from hydrogen, a hydrocarbyl group, a substituted hydrocarbyl group, a heterohydrocarbyl group, a substituted heterohydrocarbyl group, a silyl group or derivative thereof; and R1?, R2?, R3? and R

Abstract: A process for the preparation of linear alpha olefins having 2n carbon atoms from linear alpha olefins having n carbon atoms comprising the steps of (a) dimerizing a linear alpha olefin having n carbon atoms in the presence of a dimerization catalyst to produce a linear internal olefin having 2n carbon atoms; (b)(i) reacting the linear internal olefin having 2n carbon atoms produced in step (a) with a trialkylaluminium compound in the presence of a catalytic amount of an isomerization/displacement catalyst in order to cause isomerization of the linear internal olefin and to displace alkyl group(s) from said trialkylaluminium compound to form an alkyl aluminium compound wherein at least one of the alkyl groups bound to aluminium is a linear alkyl which has been derived from the isomerization of said linear internal olefin; and (b)(ii) reacting said alkyl aluminium compound with an alpha olefin optionally in the presence of a displacement catalyst so as to displace said linear alkyl from said alkyl aluminium co

Abstract: A transition metal complex which is a bis-arylimine pyridine MXn complex or a [bis-arylimine pyridine MXp+][NC?]q complex comprising a bis-arylimine pyridine ligand and M is a transition metal atom; n matches the formal oxidation state of the transition metal atom M; X is halide, optionally substituted hydrocarbyl, alkoxide, amide, or hydride; NC? is a non-coordinating anion; and p+q matches the formal oxidation state of the transition metal atom M. 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.