| abstract |
A complex suitable for use as a catalyst in the polymerisation of olefins is disclosed, having the Formula (I) wherein M is a transition metal; X represents an atom or group covalently or ionically bonded to M; T is the oxidation state of M; b is the valency of the atom or group X; A 1 to A 3 are each independently N or P or CR, with the proviso that at least one but no more than two of them are independently CR; Y 1 and Y 2 are each independently CR′ or PR′R″; Z is oxygen or NR 5 , R 5 and R 7 and each R, each R′ and each R″ are independently selected from hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl or SiR 30 3 where each R 30 is independently selected from hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl and substituted heterohydrocarbyl; but excluding those complexes having the formulae (1) and (2) where in both cases R 4 and R 6 are Me, R 5 and R 7 are 2, 4, 6-trimethylphenyl, M is Fe, T is II, X is Cl and b is 1. |