Hydrocarbons functionalized, route

The existence of a mode of hydrogenative cracking other than via the dual functional route, for the light hydrocarbons, as was indicated by Myers and Munns (23), can be demonstrated and substantiated by the use of the mixed catalyst technique. 

In most hydrocarbon operations excess gas and vapors have to disposed of safety, quickly without environmental impact. Where the gas or vapor cannot be converted into useful energy they are routed to a remote point for safe incineration, called flaring. Flares are the most economical and customary means of disposing of excess light hydrocarbon gases in the petroleum and chemical industries. The primary function of a flare is to convert flammable, toxic or corrosive vapors to environmentally acceptable gases for release into the atmosphere. Both elevated or ground flares can be used. 

It is also possible to fluorinate hydrocarbon polymers containing acid groups as a means toward functionalization. We have found that the most successful route is first to convert the acid to an acid fluoride and then to conduct the fluorination as shown in example (c) ... 

Osmium-catalysed dihydroxylation of olefins is a powerful route towards enantioselective introduction of chiral centers into organic substrates [82]. Its importance is remarkable because of its common use in organic and natural product synthesis, due to its ability to introduce two vicinal functional groups into hydrocarbons with no functional groups [83]. Prof. Sharpless received the 2001 Nobel Prize in chemistry for his development of asymmetric catalytic oxidation reactions of alkenes, including his outstanding achievements in the osmium asymmetric dihydroxylation of olefins. 

Under the same conditions, several types of hydrocarbon are also converted to fully deuterated compounds. The results are summarized in Table 1. Cydooctene was also transformed into fully deuterated cydooctene without a skeletal rearrangement. As shown in entries 2 and 3, saturated hydrocarbons have also been transformed into fully deuterated compounds. As described above, an interaction between allylic C-H bonds and palladium hydride induces the H-D exchange reaction for alkenes. H-D exchange in alkanes, however, cannot be explained in this way. Direct C-H activation without assistance from any functional group may be a route to the formation of fully deuterated alkanes. 

Intramolecular C-H insertion is, essentially, a method for the specific remote functionalization of hydrocarbons. An important implication of this for synthetic strategy is that the C-H insertion process can dissolve symmetry, thus leading from a simple precursor to a much more complex product. An alternative route to pentalenolactone E (15) takes advantage of this idea [7]. In the key step, -keto ester 13, which has a single stereo-genic center, is transformed into the tricycle 14, which has four stereogenic centers. 

Since various supported and unsupported metal oxides are oxidation catalysts for hydrocarbons, there has been interest in determining the relationship between the reduction/re-oxidation properties of the oxides and their catalytic properties. A common oxidation mechanism involves a redox cyde in which lattice oxygen is removed in the reachon and then replenished by oxygen from the gas phase. Thus there are studies to determine the energehcs of removal of oxygen from the catalysts and replenishment by various routes. These energetics have been determined as a function of catalyst formulation or modification, and as a function of the oxidation state of the catalyst [4]. 

F yrolysis of gaseous hydrocarbons at 1000-1700 °C is a common route (cf. Nos. 6 and 7 in Table 9, where two examples involving benzene are considered [441, 442]). The substrate was nickel, and dense black layers were obtained to serve as a host lattice for the lithium negative electrode. The pyrolytic carbon from benzene at 1000 °C gave a lithium GIC (CeLi) and could be cycled at 99% current efficiency [407]. Pyrolysis of epoxy Novolac resin and epoxy-functionalized silane gave a material containing silicon with a capacity of 770 mAh/g for the lithiated form [443]. 

We presented a facile route for the modification of zeolites and for the preparation of bifunctional catalysts possessing both acidic and hydrogenation functions via solid-solid reaction. Branched and higher hydrocarbons were obtained over such modified composite catalysts. Sodium migration from the surface of the iron-based catalyst to the zeolite during the solid-solid reaction accounts for the change of catalytic activity. XRD measurements exhibited evidence for Na migration. 

The oxidative functionalization of hydrocarbons is a fundamental problem in organic synthesis. Metal-complex catalysis plays an important role in the solution of this problem. In this connection, the elaboration of simple, convenient, and industrially applicable catalytic methods using cheap and easily available oxidants is very important. One of the possible routes for the creation of such methods is the joint use of metal-complex catalysis and PTC. 

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