ИСТИНА

A complex comprises a ligand (I)​, wherein each R1, which may be the same or different, is hydrogen, an optionally substituted C1-​20 hydrocarbyl group, N(R5)​2, silyl, siloxy; an optionally substituted heteroaryl group, an optionally substituted heterocyclic group or two R1 groups on adjacent carbon atoms taken together may form an optionally substituted 5- to 8-​membered fused ring; each R2, which may be the same or different is hydrogen, is hydrogen, an optionally substituted C1-​20 hydrocarbyl group, N(R5)​2, silyl, siloxy; an optionally substituted heteroaryl group, or an optionally substituted heterocyclic group; R3, which binds to the 6-​membered ring of the indenyl group, is -​(Si(R5)​2)​p-​, where p is 1 or 2, -​(C(R5)​2 )​n- where n is an integer of 2 or more; each R4 which may be the same or different, is hydrogen, an optionally substituted C1-​20 hydrocarbyl group, N(R5)​2, silyl, siloxy, an optionally substituted heteroaryl group, an optionally substituted heterocyclic group or two R4 groups on adjacent carbon atoms taken together can form an optionally substituted 5- to 8-​membered fused carbon ring; each R5, which may be the same or different, is hydrogen, an optionally substituted C1-​20 hydrocarbyl group, or two R5 groups taken together can form an optionally substituted 5- to 8-​membered ring; a is 0 to 3; b is 0 to 3; c is 0 to 4; complexed to a metal ion, M. The complexes are useful as catalysts for polymn. of olefins.