Large-ring P/O chelate nickel complex catalyzed oligomerization of ethylene to linear alpha-olefins

1,1-(Bicyclononyl-9-phosphino)hendecano acid and potassium 1,1-(biscyclohex ylphosphino) hendecylate were synthesized. A model nickel complex [eta(3)-C 8H13Ni](C8H14)P(CH2)(10)COO containing a 14-membered chelate ring was also synthesized. The catalytic activity of this large chelate ring nickel compl ex for the oligomerization of ethylene was studied and compared with that o f six-membered ring chelate nickel complexes. The influence of the chelate ring was rationalized in terms of intramolecular rotation. The 14-membered ring P/O chelate nickel complex was shown to have efficient catalytic activ ity for the oligomerization of ethylene to alpha-olefins. Copyright (C) 200 0 John Wiley & Sons, Ltd.