Catalyst for trimerization of ethylene and process for trimerizing ethylene using the catalyst

Abstract

A catalyst for trimerization of ethylene is disclosed which comprises (a) a chromium complex having a neutral multidentate ligand having a tripod structure, represented by the formula, ACrJ Q wherein A is a neutral multidentate ligand having a tripod structure, J is a carbonyl ligand or halogen, n is an integer of 0-3, and Q is at least one member selected from hydrogen, a C -C hydrocarbon group, a C -C carboxylate group, a C -C diketonato group, an amide group, an imide group, an C -C alkoxide group, a C -C thioalkoxide group, an C -C arene ligand, an C -C alkene ligand, an C -C alkyne ligand, an amine ligand, an imine ligand, an isonitrile ligand, a phosphine ligand, a phosphine oxide ligand, a phosphite ligand, an ether ligand, a sulfide ligand, a sulfone ligand and a sulfoxide ligand, and (b) a metal alkyl compound. The catalyst optionally further comprises (c) at least one compound selected from aromatic tertiary amine compounds, except for an imine, and nitrogen-containing heterocyclic compounds, and (d) a radical anion compound.