LOW-PRESSURE ETHYLENE OLIGOMERIZATION WITH A NICKEL-P-BOOLEAN-AND-O COMPLEX

The oligomerization of ethylene catalyzed by nickel-(PO)-O-boolean AND complexes at room temperature and low pressure (5 to 30 bar) yields b utenes, hexenes and octenes. The molecular weight distribution can be manipulated by variation of ethylene pressure and by addition of triph enylphosphine. An unexpected linear dependence between the growing fac tor beta of the Schulz-Flory type distribution and the pressure has be en observed. The equation: beta = 6.2 (PPh(3)/Ni)(1.2) - [0,17 P(PPh(3 )/Ni)(1.2)] allows to predict the composition of the alpha-olefins for med under different reaction conditions.