Catalysts based on 2-(2-aryloxy)quinoline or 2-(2-aryloxy)dihydroquinoline ligands
View Patent ↗Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a Group 4 metal complex that incorporates a dianionic, tridentate 2-(2-aryloxy)quinoline or 2-(2-aryloxy)dihydroquinoline ligand. In one aspect, supported catalysts are prepared by first combining a boron compound having Lewis acidity with excess alumoxane to produce an activator mixture, followed by combining the activator mixture with a support and the tridentate, dianionic Group 4 metal complex. The catalysts are easy to synthesize, support, and activate, and they enable facile production of high-molecular-weight polyolefins.
1. A catalyst useful for polymerizing olefins, comprising an activator and a complex which comprises a Group 4 transition metal and a dianionic, tridentate 2-(2-aryloxy)quinoline or 2-(2-aryloxy)dihydroquinoline ligand.
2. The catalyst of claim 1 wherein the activator is selected from the group consisting of alumoxanes, boron compounds having Lewis acidity, and mixtures thereof.
3. The catalyst of claim 1 wherein the metal is zirconium or titanium.
4. The catalyst of claim 1 wherein the ligand is a 2-(2-aryloxy)-8-anilinoquinoline.
5. The catalyst of claim 4 wherein the complex has the structure:
in which M is a Group 4 transition metal, Ar is an aryl group, each X is independently selected from the group consisting of halide, amide, alkyl, aryl, and alkaryl, and any of the ring carbons is optionally substituted with an alkyl, aryl, halide, alkoxy, trialkylsilyl, dialkylamino, or haloalkyl group, or any pair of adjacent ring carbons are joined to form a 5 to 7-membered carbocyclic or heterocyclic ring.
6. The catalyst of claim 5 wherein the complex has the structure:
in which Bn is benzyl and each R is independently selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, and tert-butyl.
7. The catalyst of claim 1 wherein the ligand is a 2,8-bis(2-aryloxy)quinoline or a 2,8-bis(2-aryloxy)dihydroquinoline.
8. The catalyst of claim 7 wherein the complex has the structure:
in which M is a Group 4 transition metal, each X is independently selected from the group consisting of halide, amide, alkyl, aryl, and alkaryl, and any of the ring carbons is optionally substituted with an alkyl, aryl, halide, alkoxy, trialkylsilyl, dialkylamino, or haloalkyl group, or any pair of adjacent ring carbons are joined to form a 5 to 7-membered carbocyclic or heterocyclic ring.
9. The catalyst of claim 8 wherein the complex has the structure:
in which Bn is benzyl and each R is independently selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, and tert-butyl.
10. The catalyst of claim 1 wherein the ligand is a 2-(2-aryloxy)-8-arylquinoline.
11. A supported catalyst of claim 1 .
12. A silica-supported catalyst of claim 2 .
13. A process which comprises polymerizing at least one of ethylene, propylene, and an α-olefin in the gas, solution, or slurry phase in the presence of the catalyst of claim 1 .
14. The process of claim 13 wherein the α-olefin is selected from the group consisting of 1-butene, 1-hexene, 1-octene, and mixtures thereof.