Catalyst for the production of olefin polymers

A compound having the formula:

• 5
• wherein:
• R1, R2, R3 and R4 are each independently selected from among hydrogen and C1-C8 hydrocarbyl groups, wherein none, one or two pairs of substituents selected from the group consisting of R1, R2, R3 and R4 are linked to form saturated or unsaturated rings;
• M is an atom selected from among the elements of Groups IV, V and VI;
• m is 1, 2, 3 or 4;
• the or each X is selected from among halide elements, C1-C8 hydrocarbyl groups, C1-C8 alkoxy groups, C1-C8 carboxylate groups and C1-C8 carbamate groups;
• n is 1, 2 or 3;
• the or each L is an organic compound containing at least one lone pair of electrons;
• Q is a divalent radical of the formula YR5R6, wherein Y is a Group 14 atom, wherein R5 and R6 are each independently selected from among hydrogen and C1-C8 hydrocarbyl groups, and wherein R5 and R6 are not linked or are linked to form a saturated or unsaturated ring;
• E is a Lewis basic group having formula (i) or (ii) below:
• —C(R7)═Z1R8, (i)
• wherein R7 and R8 are each independently selected from among hydrogen and C1-C8 hydrocarbyl groups, and wherein R7 and R8 are not linked or are linked to form a saturated or unsaturated ring;
• and
• Z1 is a nitrogen atom or a phosphorus atom, which bonds to M;
• 6
• wherein
• Z2 is an oxygen atom, a sulphur atom or a selenium atom, which bonds to M;
• and
• R9, R10 and R11 are each independently selected from among hydrogen and C1-C8 hydrocarbyl groups, wherein no pair or one pair of substituents selected from R9, R10 and R11 are linked to form a saturated or unsaturated ring.