Patent ID: 8569532

Claim:
A complex comprising a ligand of formula (I): wherein each R 1 , which may be the same or different, is hydrogen, an optionally substituted C 1-20 hydrocarbyl group, N(R 5 ) 2 , silyl, siloxy; an optionally substituted heteroaryl group, an optionally substituted heterocyclyl group or two R 1 groups on adjacent carbon atoms taken together to form an optionally substituted 5- to 8-membered fused ring; each R 2 , which may be the same or different is hydrogen, is hydrogen, an optionally substituted C 1-20 hydrocarbyl group, N(R 5 ) 2 , silyl, siloxy; an optionally substituted heteroaryl group, or an optionally substituted heterocyclyl group; R 3 , which binds the 5-membered ring of the top ligand and to the 6-membered ring of the indenyl group, is —(Si(R 5 ) 2 ) p —, where p is 1 or 2, —(C(R 5 ) 2 ) n — where n is an integer of 2 or more; each R 4 which are the same or different, is hydrogen, an optionally substituted C 1-20 hydrocarbyl group, N(R 5 ) 2 , silyl, siloxy, an optionally substituted heteroaryl group, an optionally substituted heterocyclyl group or two R 4 groups on adjacent carbon atoms taken together form an optionally substituted 5- to 8-membered fused carbon ring; each R 5 , which are the same or different, is hydrogen, an optionally substituted C 1-20 hydrocarbyl group, or two R 5 groups taken together 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.