Catalysis olefin oligomerization

A particularly challenging situation in catalysis in general and in olefin oligomerization in particular is that of stereoselectivity control, including diastereoselectivity and enantioselectivity (6). 

P. Travers, Olefin oligomerization with homogeneous catalysis, Petrol. Technol. Quarter fPTQJ, (1999) 141. 

The advent of the energy crisis has caused us to examine traditional views of the relative costs of different monomers and to consider the potential of less costly monomers for polymerization. One can expect that catalysis of the coordinated anionic type will play a major role in any new developments in olefin and diene polymerizations. Finally, one should recall that Ziegler catalysts have found many uses in other areas of chemistry such as metathesis of olefins, oligomerization, isomerization, hydrogenation, and alkylation. The vast scope of these catalysts will almost certainly achieve a wider range as these types of studies continue in the future. 

On the technical scale, olefin polymerization is based on the activation of a suitable zirconocene precursor, typically Cp2ZrMe2 or Cp2ZrCl2, by a strong Lewis acid as co-catalyst. Mechanistic studies on Ziegler-Natta-like polymerization have long focused on the role of cationic alkylzirconocene species in the catalysis. There have been previous mass spectrometric studies of isolated metallocene ions in the gas phase, most notably by Richardson and co-workers. The failure to observe olefin oligomerization in this study was attributed to incomplete thermaliza-... 

Compounds Ni(olefin)2 have significant application in catalysis. Olefin-carbonyl complexes of the type [Ni(CO)j, (olefin) ] are not known. Their existence as unstable intermediate compounds in many reactions results from catalytic properties of tetracarbonylnickel in olefin oligomerization processes, oxo synthesis, olefin isomerization, etc. 

Mantilla, A., Ferrat, G., Lopez-Ortega, A., Romero, E., Tzompantzi, F., Torres, M., et al. (2005a). Catalytic behavior of sulfated Ti02 in light olefins oligomerization. Molecular Journal of Catalysis A Chemical, 228, 333—338. 

Gibson VC, Solan GA (2010) Olefin oligomerizations and poljmerizatifflis catalyzed by iron and cobalt complexes bearing bis(imino)pyridine ligands, hr Bullock RM (ed) Catalysis without precious metals. Wiley-VCH, Weinheim. doi 10.1002/9783527631582.ch5... 

Kucherov, A. W., Catalysis of higher olefin oligomerization, Kinet. Katal., 30, 193, 1989 (Russian). 

Base catalysis is most effective with alkali metals dispersed on solid supports or, in the homogeneous form, as aldoxides, amides, and so on. Small amounts of promoters form organoalkali comnpounds that really contribute the catalytic power. Basic ion exchange resins also are usebil. Base-catalyzed processes include isomerization and oligomerization of olefins, reactions of olefins with aromatics, and hydrogenation of polynuclear aromatics. 

Biphasic catalysis is not a new concept for oligomerization chemistry. On the contrary, the oligomerization of ethylene was the first commercialized example of a biphasic, catalytic reaction. The process is known under the name Shell Higher Olefins Process (SHOP) , and the first patents originate from as early as the late 1%0 s. 

Under the reaction conditions employed, the oligomerization is living the aluminium is removed from the chain in a separate process step [2]. Further research on the Aufbau reaction led to the discovery of transition metal catalyzed olefin polymerization (Ziegler-Natta catalysis) [3]. 

The Shell higher olefins process, or SHOP, is one of the most important large-scale processes in the chemical industry which uses homogeneous catalysis [79]. In this process, ethene is oligomerized to medium- and long-chain a-olefins. The products... 

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