Polymerization catalysts, preparation of polyolefins, organotransition metal compounds and ligands
View Patent ↗The invention relates to non-metallocene catalyst systems useful for preparing olefin homopolymers or copolymers. The catalyst systems comprise a cocatalyst and a Group 3-10 transition metal compound that incorporates a diimine ligand in which sp 2 -hybridized carbons of the imine groups are joined by a specific divalent one- or two-membered bridge (Y) comprising nitrogen and/or oxygen. The invention includes the diimine ligands, the transition metal compounds, the catalyst systems, and processes for making the ligands, transition metal compounds, catalyst systems, and olefin homopolymers or copolymers.
1. A transition metal compound of the formula (I)
where
M is an element of group 3, 4, 5, 6, 7, 8, 9 or 10 of the Periodic Table of the Elements or the lanthanides,
X are identical or different and are each an organic or inorganic anionic monovalent ligand, where two radicals x may also be joined to form a divalent radical,
n is 1, 2, 3 or 4,
L 1 is an organic or inorganic uncharged ligand,
h is an integer from 0 to 4,
R 1 and R 1′ can be identical or different and are each hydrogen or an organic radical having from 1 to 40 carbon atoms,
R 2 and R 2′ can be identical or different and are each a substituted or unsubstituted C 6 -C 40 -aryl radical or C 2 -C 40 -heteroaromatic radical containing at least one heteroatom selected from the group consisting of O, N, S and P,
and
Y is a divalent group between the two sp 2 -hybridized carbon atoms and is selected from the group consisting of the two-membered bridges —N(R 3 )—N(R 4 )— and —O—N(R 5 )— and the one-membered bridges —O—, —N(R 6 )—, —N(OR 7 )— and —N(NR 8 R 9 )—,
where
R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9 are identical or different and are each hydrogen or an organic radical having from 1 to 40 carbon atoms, where two adjacent radicals may also form a divalent organic group having from 1 to 40 carbon atoms which together with the atom or atoms connecting its ends forms a heterocyclic ring system.
2. A process for preparing a transition metal compound, which comprises reacting a transition metal compound with a ligand system of the formula (II)
where
R 1 and R 1′ can be identical or different and are each hydrogen or an organic radical having from 1 to 40 carbon atoms,
R 2 and R 2′ can be identical or different and are each a substituted or unsubstituted C 6 -C 40 -aryl radical or C 2 -C 40 -heteroaromatic radical containing at least one heteroatom selected from the group consisting of O, N, S and P,
and
Y is a divalent group between the two sp 2 -hybridized carbon atoms and is selected from the group consisting of the two-membered bridges —N(R 3 )—N(R 4 )— and —O—N(R 5 )— and the one-membered bridges —O—, —N(R 6 )—, —N(OR 7 )— and —N(NR 8 R 9 )—,
where
R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9 are identical or different and are each hydrogen or an organic radical having from 1 to 40 carbon atoms, where two adjacent radicals may also form a divalent organic group having from 1 to 40 carbon atoms which together with the atom or atoms connecting its ends forms a heterocyclic ring system.