Patent ID: 8309779

Claim:
A method of producing 1-hexene by selectively trimerizing ethylene using a catalyst system comprising a transition metal or transition metal precursor, a promoter and a ligand represented by any one of the following formulas 1 to 4, wherein the promoter is methylaluminoxane (MAO) or ethylaluminoxane (EAO) and the ligand is sterically asymmetric with respect to a plane of symmetry: wherein R 1 , R 2 , R 3 and R 4 are each independently hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl or substituted heterohydrocarbyl, R 5 and R 6 are each independently hydrocarbyl or substituted hydrocarbyl, and A is hydrocarbylene, substituted hydrocarbylene, heterohydrocarbylene or substituted heterohydrocarbylene.