Homogeneous catalysis dimerization

Another example of homogeneous catalysis in aqueous solution is the dimerization of benzaldehyde catalyzed by cyanide ion, CN- (Wilkinson, 1980, p.28) ... 

Another example is butene dimerization catalyzed by nickel complexes in acidic chloroaluminates 14). This reaction has been performed on a continuous basis on the pilot scale by IFF (Difasol process). Relative to the industrial process involving homogeneous catalysis (Dimersol process), the overall yield in dimers is increased. Similarly, selective hydrogenation of diene can be performed in ionic liquids, because the solubility of dienes is higher than that of monoene, which is higher than that of paraffins. In the case of the Difasol process, a reduction of the volume of the reaction section by a factor of up to 40 can be achieved. This new Difasol technology enables lower dimer (e.g., octenes) production costs 14). 

Heterometal alkoxide precursors, for ceramics, 12, 60-61 Heterometal chalcogenides, synthesis, 12, 62 Heterometal cubanes, as metal-organic precursor, 12, 39 Heterometallic alkenes, with platinum, 8, 639 Heterometallic alkynes, with platinum, models, 8, 650 Heterometallic clusters as heterogeneous catalyst precursors, 12, 767 in homogeneous catalysis, 12, 761 with Ni—M and Ni-C cr-bonded complexes, 8, 115 Heterometallic complexes with arene chromium carbonyls, 5, 259 bridged chromium isonitriles, 5, 274 with cyclopentadienyl hydride niobium moieties, 5, 72 with ruthenium—osmium, overview, 6, 1045—1116 with tungsten carbonyls, 5, 702 Heterometallic dimers, palladium complexes, 8, 210 Heterometallic iron-containing compounds cluster compounds, 6, 331 dinuclear compounds, 6, 319 overview, 6, 319-352... 

Smutny EJ (1967) Oligomerization and dimerization of butadiene under homogeneous catalysis. Reaction with nucleophiles and synthesis of 1,3,7-octatriene. J Am Chem Soc... 

Description Butenes enter the Dimersol-X process, which comprises three sections. In the reactor section, dimerization takes place in multiple liquid-phase reactors (1) using homogeneous catalysis and an efficient recycle mixing system. The catalyst is generated in situ by the reaction of components injected in the recycle loop. The catalyst in the reactor effluent is deactivated in the neutralization section and separated (2). The stabilization section (3) separates unreacted olefin monomer and saturates from product dimers while the second column (4) separates the octenes. A third column can be added to separate dodecenes. 

Description Butenes enter the Dimersol-X process, which comprises three sections. In the reactor section, dimerization takes place in multiple liquid-phase reactors (1) using homogeneous catalysis and an efficient recycle mixing system. The catalyst is generated in situ by... 

Metallacyclopentanes are of considerable importance as intermediates in catalytic alkene dimerization (see Oligomerization Polymerization by Homogeneous Catalysis). 

Dimerization reactions have been the subject of recent reviews [1,2]. For applications of homogeneous catalysis, see [3]. 

Homogeneous catalysis with defined soluble transition metal complexes as catalysts has become one of the most effective means of transforming simple olefins into more valuable materials. The technically important hydroformylation of olefins to aldehydes or alcohols the Wacker process the dimerization of propylene to linear hexenes the oligomerization of ethylene to linear a-olefins are only a few examples. A feature common to all these processes is the insertion of a substrate olefin molecule, which is coordinatively bonded to the transition metal center M, into a metal-carbon or metal-hydrogen bond present at the same center ... 

In general, however, many calculations which aim to explain chemisorption on surfaces still involve interactions with small metal clusters. This has been a field of great theoretical activity, and it is not possible within the scope of this review to cover all computational studies of chemisorption on metal clusters. Some of the. calculations, particularly those whose aim is to elucidate the transfer of charge from cluster to adsorbate or the reactivity of molecules on metal clusters, are especially relevant to catalytic processes, though, and attention will focus on these. Only calculations which deal with clusters of at least three metal atoms will be mentioned here although there are many calculations involving isolated metal atoms, or metal dimers, these are probably more relevant to the fields of homogeneous catalysis or... 

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