PROPADIENE OLIGOMERIZATION CATALYZED BY NICKEL(0) PHOSPHINE COMPLEXES IMMOBILIZED ON PHOSPHINATED POLY(STYRENE DIVINYLBENZENE) SUPPORT

Nickel(0) immobilized on diphenylphosphinated gel-type poly(styrene-divinylbenzene) support is an efficient catalyst of propadiene oligomerization leading to the same mixture of cyclic trimer, tetramer, and pentamer as in homogeneous reaction. The catalyst can be recycled four times without the need for reactivation before the activity drops considerably. Oligomer selectivities point to the coordination of phosphine ligand during oligomerization which, in the absence of free triphenylphosphine, is evidence against catalysis by free nickel(0) in solution. Of several different solvents toluene is the solvent of choice as it gives low leaching values and the highest yield.