Oligomerization of Ethylene Using a Diphosphine Palladium Catalyst

The palladium diphosphine complex 4 converts ethylene to hyperbranched unsaturated oligomers (Mn ≈ 330 g/mol) at 22 °C. In addition to the high stability of this catalyst observed at temperatures up to 75 °C, an increase of the reaction temperature leads to a decrease in branching densities of the oligomers, in sharp contrast to the palladium and nickel diimine catalyst systems. One-pot oligomerizations/hydrogenations were carried out to form hyperbranched saturated oligomers.