Linear dimerisation of 1-olefins catalysed by complexes of nickel β-diketonates and aluminium alkyls

Abstract

The dimerisation of propene and of other 1-olefins has been studied with the homogeneous catalyst system nickel acetylacetonate–diethylaluminium ethoxide and with related systems containing nickel and palladium complexes of various β-diketones and β-keto-esters and a variety of alkyl compounds of aluminium and other metals. Products of remarkable linearity were obtained; selectivity to linear dimers was in the range 75–85% and was little affected by a wide variety of both physical and chemical variations which were made on the system. Marked differences are observed between products of this system and those of similar transition-metal systems containing components of high Lewis acidity. The nature of the active species is discussed and a reaction mechanism is proposed.