3404-67-9Relevant academic research and scientific papers
Oligomerization of 1-butene with a homogeneous catalyst system based on allylic nickel complexes
Behr,Bayrak,Peitz,Stochniol,Maschmeyer
, p. 41372 - 41376 (2015/05/27)
The oligomerization of 1-butene with a nickel-based catalyst system constitutes an elegant synthesis method for obtaining linear octenes from readily available chemicals. It is well known that the bis-(cyclooctadiene)nickel(0)-complex (Ni(COD)2) can be used in combination with 1,1,1,5,5,5-hexafluoroacetylacetone (hfacac) forming [Ni-1] as a catalyst for the dimerization of 1-butene, which produces a linear octene yield of 75-83% at reaction temperatures between 70-80 °C. We are the first to demonstrate that it is also possible to use allylic nickel complexes in combination with hfacac to produce linear octenes with a selectivity of 70% under very mild reaction conditions and at low catalyst concentrations. Additionally the catalyst can be formed simply by adding the activator hfacac to a solution of the allylic nickel complex. No complicated synthesis or purification is needed.
Comparative Dimerization of 1-Butene mith a Variety of Metal Catalysts, and the Investigation of a New Catalyst for C-H Bond Activation
Small, Brooke L.,Schmidt, Roland
, p. 1014 - 1020 (2007/10/03)
Catalytic dimerization of 1-butene by a variety of catalysts is carried out, and the products are analyzed by gas chromatography and mass spectrometry. Catalysts based on cobalt and iron can produce highly linear dimers, with the cobalt-based dimers exceeding 97% linearity. Catalysts based on vanadium and aluminum prefer to make branched dimers, which are most often methyl-heptenes in the case of vanadium and almost exclusively 2-ethyl-1-butene in the case of aluminum. The vanadium catalyst also produces substantial amounts of dienes and alkanes, suggesting a competing hydrogenation/dehydrogenation pathway that appears to involve vinyl C-H bond activation. Nickel catalysts are generally less selective than those based on iron or cobalt for making linear dimers, but they can make dimers with 60% linearity. The major by-products for the nickel systems are trisubstituted internal olefins. An important side reaction that must be considered for dimerization reactions is 1-butene isomerization to 2-butene, which makes recycling the butene difficult for a linear dimerization process. Aluminum, iron, and vanadium systems promote very little isomerization, but nickel and cobalt systems tend to isomerize the undimerized substrate heavily.
