Striking different behavior in the activation of α-olefins by homogeneous and heterogenized catalysts based on η5-cyclopentadienyl nickel derivatives

• Published in: Journal of molecular catalysis. A, Chemical Chemical, 1996-09, Vol.111 (3), p.273-280
• Main Authors: Raspolli Galletti, A.M., Geri, G., Sbrana, G., Marchionna, M., Ferrarini, P.
• Format: Article
• Language: English
• Subjects: Applied sciences; Catalysis; Catalysts: preparations and properties; Chemistry; Exact sciences and technology; General and physical chemistry; Heterogenized catalysts; Nickel catalysts; Oligomerization; Organic polymers; Physicochemistry of polymers; Polymer support; Polymerization; Preparation, kinetics, thermodynamics, mechanism and catalysts; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/1381-1169(96)00199-9

Homogeneous η5-cyclopentadienyl nickel catalysts have been applied to ethylene oligomerization. Their activity, enhanced by the presence of Al(OEt)Et 2 as co-catalyst, resulted the highest up to now reported for this type of complexes. The same catalytic systems were also able to oligomerize propylene as well as ethylene/propylene mixtures. In particular propylene was converted into branched dimers, mostly 2,3-dimethylbutenes. Heterogenization of the above system, carried out by anchoring the nickel derivative to a styrene/divinylbenzene resin properly functionalized with the cyclopentadienyl group, caused a drastic change of the selectivity of the process, ethylene polymerization to HDPE taking place instead of oligomerization.