Catalysts for olefin polymerization or oligomerization
View Patent ↗Novel iron and cobalt complexes of certain novel tricyclic ligands containing a “pyridine” ring and substituted with two imino groups are polymerization and/or oligomerization catalysts for olefins, especially ethylene. Depending on the exact structure of the ligand, and polymerization process conditions, products ranging from α-olefins to high polymers may be produced. The polymers, especially polyethylenes, are useful for films and as molding resins.
1. An iron or cobalt complex of a ligand of the formula
wherein:
m and n are each independently an integer of 2 to 5;
each R 2 and R 3 is independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or a functional group;
R 4 is hydrogen, hydrocarbyl, substituted hydrocarbyl, or a functional group; and
R 5 and R 6 are each independently hydrocarbyl or substituted hydrocarbyl.
2. The complex as recited in claim 1 wherein m and n are both 2 or 3, R 4 is hydrogen, and wherein R 2 and R 3 is hydrogen.
3. The complex as recited in claim 1 wherein R 5 and R 6 are each independently aryl or substituted aryl.
4. The complex as recited in claim 3 wherein R 5 and R 6 are each independently phenyl, substituted phenyl, 1-pyrrolyl or substituted 1-pyrrolyl.
5. The complex as recited in claim 1 wherein R 5 and R 6 are each independently aryl or substituted aryl, m and n are both 2 or 3, R 4 is hydrogen, and every R 2 and R 3 is hydrogen.
6. The complex as recited in claim 1 wherein the complex is an iron complex.