Olefin isomerization industrial applications

If cobalt carbonylpyridine catalyst systems are used, the formation of unbranched carboxylic acids is strongly favored not only by reaction of a-olefins but also by reaction of olefins with internal double bonds ( contrathermo-dynamic double-bond isomerization) [59]. The cobalt carbonylpyridine catalyst of the hydrocarboxylation reaction resembles the cobalt carbonyl-terf-phos-phine catalysts of the hydroformylation reaction. The reactivity of the cobalt-pyridine system in the hydrocarboxylation reaction is remarkable higher than the cobalt-phosphine system in the hydroformylation reaction, especially in the case of olefins with internal double bonds. This reaction had not found an industrial application until now. 

Olefin isomerization (Continued) industrial applications, 9, 95 ligand synthesis, 96 rhodium-catalyzed, 98 Olefins ... 

Curtin-Hammett principle, 23 industrial applications, 8, 26 mechanism, 21 phosphine ligands, 7, 18 reaction conditions, 18 scope and limitations, 27 Wilkinson complex, 17 Rhodium-catalyzed olefin isomerization ab initio calculations, 110... 

The pioneer work in this field was carried out on polystyrene-supported acid catalysts [161]. Thereafter, several works on the use of sulfonic, strong acidic cation exchangers as acid catalysts were reported for alkylation, hydration, etherification, esterification, cleavage of ether bonds, dehydration, and aldol condensation [162,168-171], Besides, industrial applications of these materials were evaluated with reactions related to the chemistry of alkenes, that is, alkylation, isomerization, oligomerization, and acylation. [163,169], Also, Nation, an acid resin which has an acid strength equivalent to concentrated sulfuric acid, can be applied as an acid catalyst. It is used for the alkylation of aromatics with olefins in the liquid or gas phases and other reactions however, due to its low surface area, the Nation resin has relatively low catalytic activity in gas-phase reactions or liquid-phase processes where a nonpolar reactant or solvent is employed [166],... 

Addition reactions to olefins can be used both for the construction and for the functionalization of molecules. Accordingly, chiral catalysts have been developed for many different types of reactions, often with very high enantioselectiv-ity. Unfortunately, most either have a narrow synthetic scope or are not yet developed for immediate industrial application due to insufficient activities and/ or productivities. These reactions include hydrocarbonylation [Ilf], hydrosilyla-tion [12 i], hydroboration [12j], hydrocyanation [12 k], Michael addition [11 g, 121, 12 m], Diels-Alder reaction [11 h, 12n] and the insertion of carbenes in C-H bonds [Hi, 12p, 12q, 38], Cyclopropanation [Hi, 12p, 12q] and the isomerization of allylamines [12 s] are already used commercially for the manufacture of Cilastatin (one of the first industrial processes) [12 r], and citronellol and menthol (presently the second largest enantioselective process) [12t] respectively. 

In the last years a great interest was paid to the catalytic properties of iron-containing zeolites that show interesting activities in different industrial reactions. The Fe-BEA zeolite is reported to be a good catalyst in the vapour phase alkylation processes [1], the Fe-TON zeolite shows very high activity and selectivity in the olefin isomerization [2, 3]. Finally, new applications of zeolitic catalysts in the partial oxidation catalysis, such as the Solatia Inc. processes for benzene hydroxylation to phenol using Fe-MFI, open a novel route for the use of zeolites in oxidation processes [4, 5]. On the other hand, the catalytic properties of the metal-modified MOR type zeolite in the isomerization process are well known. 

There is not very often accordance among the different models for the acidity prediction of a given oxide structure. Moreover, it is also hard to justify the predicted acid properties with the catalytic activity of the oxide composition this is the case of titania-silica system [67, 104]. Ti02 -Si02 mixed oxide is a very important industrial material and catalyst in both the amorphous and crystalline phases which found several industrial applications (e.g., isomerization of olefins, epoxidation of olefins... 

Olefins are also susceptible to photodegradation reactions other than cycloaddition reactions (43). The olefin bond is susceptible to E(trans)-Z(cis) isomerization as well as oxidation (Fig. 107) (154). Photochemical E-Z isomerization has a major role in photobiological systems and has practical applications in vitamin A and vitamin D industrial processes... 

The following examples illustrate the application of high-throughput screening tools together with heuristic search algorithms in the development of new enhanced catalyst for two fields of industrial interest, olefin epoxidation and the isomerization of light paraffins. 

As shown in equation 7.59, OA of the aldehyde yields the cis-hydridoacylrhodium complex, 39. Heating results in ligand dissociation to give 40, which undergoes migratory deinsertion (to be discussed in Chapter 8) to produce 41. Isomerization of 41 to a d.v-hydridoalkyl complex presumably occurs before final the final RE step to yield the C-H elimination product. These reactions have applications in catalytic industrial process known as olefin hydroformylation (Section 9-2). Equation 7.60 illustrates straightforward RE to form a new C-H bond. 

Aluminum bromide has been finding increasing application as an acid catalyst in organic synthesis it has recently become of industrial importance in the alkylation of aromatic hydrocarbons with ethylene, and in the isomerization of normal hydrocarbons. It is also used in the polymerization of olefins, and to some extent in the Friedel-Crafts reaction. It has been found particularly useful in such reactions since it is not only more soluble in organic media, but also more active catalytically than aluminum chloride. Winter and Cramer have described a procedure for pre-... 

The hydroformylation of mixtures of Cg-olefins is a process with huge economic importance. A typical example is di-n-butene, consisting of isomeric -octenes, methylheptenes, and dimethylhexenes. The mixture is produced from Raffinate II, in which isomeric butenes are dimerized (e.g., by IFP Dimersol [47] or Octol process [48]). Hydroformylation of di- -butene produces linear and alkyl-branched Cg-aldehydes, which are converted to diisononyl phthalate (DINP), another additive for flexible PVC with immense industrial relevance. For this application, the use of terminal aldehydes is preferred. 

Homogeneous catalysts play an important role in industry as well as in research laboratories. Established applications include, for example, polymerization processes with zirconocene and its derivatives, rhodium- or cobalt-catalyzed hydroformylation of olefins, and enantioselective isomerization catalysts for the preparation of menthol. In contrast to heterogeneous catalysts, more experimental studies of reaction mechanisms are available and the active species can be characterized experimentally in some cases. Most catalysts are based on transition metal compounds, for which electronic structures and properties are well studied theoretically. A substantial number of elementary reactions, such as reductive elimination, oxidative addition, alkene or carbonyl migratory insertion, etc., have been experimentally Studied in detail by means of isotopic, NMR, and IR studie.s, as well as theoretically. ... 

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