Hydrogen chloride, from oxidation

The manufacture and uses of oxiranes are reviewed in (B-80MI50500, B-80MI50501). The industrially most important oxiranes are oxirane itself (ethylene oxide), which is made by catalyzed air-oxidation of ethylene (cf. Section 5.05.4.2.2(f)), and methyloxirane (propylene oxide), which is made by /3-elimination of hydrogen chloride from propene-derived 1-chloro-2-propanol (cf. Section 5.05.4.2.1) and by epoxidation of propene with 1-phenylethyl hydroperoxide cf. Section 5.05.4.2.2(f)) (79MI50501). 

There are several examples of the 1,2-elimination of hydrogen chloride from 9-(2-chloroethyl)carbazoles, using potassium hydroxide in ethanol, generating the 9-vinylcarbazoles. 3-Dimethylamino-9-(2-hydroxyethyl) carbazole comparably lost water on base treatment. Dimethylamine displacement of halogen, then amine N-oxide formation and elimination was utilized to produce 9-alkenylcarbazoles with four, five, and six carbon atoms from the corresponding cu-haloalkyl carbazoles. ... 

It has been possible to correlate yohimbine with the corynane group by opening ring E (5). The reduction product (XI) of yohimbone (IX) with sodium borohydride was converted as shown to the corresponding chloride (XII). Elimination of hydrogen chloride from this and oxidation of the unsaturated base (XIII) yielded a dialdehyde (XIV) whose bis-semicarbazone on reduction with hydrazine gave dihydrocorynantheane (XV), the absolute configuration of which had already been established (Vol. 7, p. 37). 

AI3-52349 Dichlorooxovanadium EINECS 233-617-7 NSC 79625 Vanadium chloride oxide Vanadium dichloride oxide Vanadium, dichlorooxo- Vanadium oxychloride Vanadyl chloride Vanadyl dichlorlde. Strong reducing agent, used in purification of hydrogen chloride from arsenic and as a mordant in printing fabrics. Green crystals d = 2.88 disproportionates at 384° soluble in EtOH, AcOH, decomposes with H2O. Atomergic Chemetals Noah Chem. 

Elimination of hydrogen chloride from sulfinyl chlorides by means of triethylamine709 has been used in a few cases to afford sulfines (an alternative method is the oxidation of diaryl thioketones by peracids710) ... 

The elimination of hydrogen chloride from hydroxamoyl chlorides occurs in refluxing toluene, as evidenced by the fact that the 1,3-cycloadducts of benzonitrile oxide with olefins and acetylenes are obtained For... 

Nitrile oxides (R-C=N -0 ), which can be generated by elimination of hydrogen chloride from chlorooximes (RC(Cl)=NOH), or by dehydration of nitro compounds (RCH2NO2), readily add to alkenes and to alkynes generating five-membered heterocycles. Addition to an alkene produces a dihydroisoxazole (isoxazoline), unless the alkene also incorporates a group capable of being eliminated in a step after the cycloaddition isoxazolines can sometimes be dehydrogenated to the aromatic system. ... 

Industrially, ethylene oxide is manufactured by the direct oxidation of ethylene with oxygen. The elimination of hydrogen chloride from ethylene chlorohydrin is no longer carried out commercially. 

Propylene oxide and 1,2-butylene oxide cyclic ethers find their largest use as chemical intermediates. Both oxides react readily with dilute amounts of mineral acids (e.g., hydrochloric acid) to form the chlorohydrin addition product. This reactivity with acid make these epoxy solvents valuable acid acceptor-type stabilizers for several chlorinated solvents. Trace amounts of hydrogen chloride from chlorinated solvent degradation is immediately neutralized by reaction with the propylene or 1,2-butylene oxide stabilizer. Reaction of propylene oxide with an alcohol or phenol in the presence of an acid catalyst yields the monoether of propylene glycol (see Chapter 13 for the glycol ethers). 

The nitrosyl process (See chapter 10.2.2) is one way to recover chlorine from hydrogen chloride by oxidizing with oxygen or air. 

By oxidation with permanganate it forms pinonic acid, C,oH,<503, a monobasic acid derived from cyclobutane. With strong sulphuric acid it forms a mixture of limonene, dipentene, terpinolene, terpinene, camphene and p-cymene. Hydrogen chloride reacts with turpentine oil to give CioHijCl, bomyl chloride, artificial camphor . 

Once the principal route to vinyl chloride, in all but a few percent of current U.S. capacity this has been replaced by dehydrochlorination of ethylene dichloride. A combined process in which hydrogen chloride cracked from ethylene dichloride was added to acetylene was advantageous but it is rarely used because processes to oxidize hydrogen chloride to chlorine with air or oxygen are cheaper (7) (see Vinyl polymers). 

There are several processes available for the manufacture of cryoHte. The choice is mainly dictated by the cost and quaUty of the available sources of soda, alumina, and fluoriae. Starting materials iaclude sodium aluminate from Bayer s alumina process hydrogen fluoride from kiln gases or aqueous hydrofluoric acid sodium fluoride ammonium bifluoride, fluorosiUcic acid, fluoroboric acid, sodium fluosiUcate, and aluminum fluorosiUcate aluminum oxide, aluminum sulfate, aluminum chloride, alumina hydrate and sodium hydroxide, sodium carbonate, sodium chloride, and sodium aluminate. 

Sulfur dioxide [7446-09-5] is formed as a result of sulfur oxidation, and hydrogen chloride is formed when chlorides from plastics compete with oxygen as an oxidant for hydrogen. Typically the sulfur is considered to react completely to form SO2, and the chlorine is treated as the preferred oxidant for hydrogen. In practice, however, significant fractions of sulfur do not oxidi2e completely, and at high temperatures some of the chlorine atoms may not form HCl. 

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