Industrial processes hydrogen halides

When an alkene is used in the alkylation of arenes, metal halides with hydrogen halide or water as cocatalyst, protic acids, and acidic oxides can be used as catalysts. Both linear and cyclic alkenes are used in alkylations. Alkylation with alkenes is usually preferred in industry because the processes are simpler and olefins are readily and cheaply available in pure form from petroleum refining processes. 

Elimination of hydrogen halide from haloalkanes to produce alkenes is an important process in organic synthesis and industry. Realization of this reaction under PTC conditions requires continuous transfer of base (OH anions) into the organic phase ... 

Another important process involving oxidative addition of alkyl halide is found in the hrst step in Monsanto process, an important industrial process to convert methanol into acetic acid with carbon monoxide at 150-200°C under 30-60 bar of CO [24]. In the Monsanto process methyl iodide is formed first from methanol and hydrogen iodide, added as the promoter to the catalytic system. The subsequent reaction of methyl iodide with a rhodium(I) species forms a methylrhodium(III) iodide species hy oxidative addition (Eq. 1.2). 

Elimination of hydrogen halides from haloalkanes and haloalkenes is an important process of synthesis of alkenes and alkynes, widely used in laboratories and industry. It is usually executed via action of strong bases NaOH, KOH, alkoxides, or trialkylamines on haloalkanes in homogeneous media. 

The ionic liquid can, for example, be added to the butene effluent from the Dimersol process to obtain octenes by butene dimerization the octene can be carbonylated (Section 4.6) and hydrogenated to wo-nonanol, used to make phthalate plasticizers. In the case of the Phillips trimerization process the use of an ionic liquid allows an easy separation of the trimers and the catalyst for recycling (see also reviews to Section 5.5). However, the industrial use as solvents of ionic liquids, containing halide species (especially anions such as Bp4, PFg, or AlCU ) has the disadvantage that they readily break down to give HX, which can adversely affect the reaction. New types of non-halide containing ionic liquids are being actively researched. 

The oxidation of alcohols to carbonyl compounds is one of the most fundamental and important processes in the fine chemical industry. The classical methodology is based on the stoichiometric use of heavy metals, notably Cr and Mn (1,2). Alternatively metal-free oxidation, such as the Swern and Pfitzner-Moffat protocols, is based on e.g., dimethylsulfoxide as oxidant in the presence of an activating reagent such as N,N -dicyclohexylcarbodiimide, an acid anhydride or acid halide (3). Although the latter methods avoid the use of heavy metals, they usually involve moisture-sensitive oxidants and environmentally undesirable reaction media, such as chlorinated solvents. The desired oxidation of alcohols only requires the formal transfer of two hydrogen atoms, and therefore the atom economy of these methods is extremely disadvantageous. The current state of the art in alcohol oxidations... 

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