NOVEL POLYMER-SUPPORTED BETA-DIKETONATE NICKEL-CATALYSTS FOR ALPHA-OLEFIN ACTIVATION

Styrene-divinylbenzene resins were used for the synthesis of different polymer-bound beta-diketones, obtained by anchoring the chelating gro up through either the central or the lateral position. The heterogeniz ed diketone ligand was subsequently reacted with Ni(COD)(2) analogousl y to hb the corresponding homogeneous catalysts active in alpha-olefin oligomerization. The heterogenized catalysts showed a good activity o nly when the central position of the chelate moiety was free. Heteroge nization caused a significant change of selectivity: olefin oligomeriz ation was accompanied by the formation of a large amount of in terms o f steric effects caused by the bulky polymeric ligand. (C) 1998 John W iley & Sons, Ltd.