Chlorohydrin ethylene

Ethylene Chlorohydrin. Two industrial processes were used in the synthesis of ethylene chlorohydrin,182 191 which, in turn, was transformed to ethylene oxide. Since the direct oxidation of ethylene to ethylene oxide is more economical, these technologies are being abandoned. 

Ethylene was reacted with chlorine water, or with a mixture of hydrated lime and chlorine. In the latter case the Ca(OCl)2 formed decomposes to yield HOC1. The aqueous opening of the intermediate chloronium ion leads to the formation of the product. Ethylene chlorohydrin then was cyclized to ethylene oxide by addition of calcium hydroxide. 

lARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol 60, Some industrial chemicals, pp 45-71. Lyon, International Agency for Research on Cancer, 1994. 

Connolly RB, Jaeger RJ Acute hepatotoxicity of ethylene and halogenated ethylenes after PCB pretreatment. Environ Health Perspect 21 131, 1977 

Hamm TE Jr, Guest D, Dent JG Chronic toxicity and oncogenicity bioassay of inhaled ethylene in Fischer-344 rats. Fundam Appl Toxicol 4 473-478, 1984 

Rostron C Ethylene metabolism and carcinogenicity. Food Chem Toxicol 24 70, 1985 

Vergnes JS, Pritts IM Effects of ethylene on micronucleus formation in the bone marrow of rats and mice following four weeks of inhalation exposure. Mutat Res 324(3) 87-91, 1994 

Coefficient of expnnsion 55 C Flash point (Cleveland O C ) Freesing point Molecular weight Pounds per gallon 20 C Solubility in water 20 C Solubility of water in solvent 20 C Vapor pressure 20 C 

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HOCHj CHjOH. Colourless, odourless, rather viscous hygroscopic liquid having a sweet taste, b.p. 197 C. Manufactured from ethylene chlorohydrin and NaHC03 solution, or by the hydration of ethylene oxide with dilute sulphuric acid or water under pressure at 195°C. Used in anti-freezes and coolants for engines (50 %) and in manufacture of polyester fibres (e.g. Terylene) and in the manufacture of various esters used as plasticizers. U.S. production 1979 1 900 000 tonnes. 

BrCHisCHjBr + 2NaOH —> HOCHjCHisOH + 2NaBr Industrially, it is produced directly from ethylene by the addition of hypo, chlorous acid, followed by treatment of the resulting ethylene chlorohydrin with sodium bicarbonate solution ... 

ClCHjCHjOH + NaHCOj —> HOCHjCHjOH + COj + NaCl When ethylene chlorohydrin is heated with sodium hydroxide solution, the highly reactive cyclic ether, ethylene oxide, is formed ... 

Methyl acrylate is usually prepared from ethylene chlorohydrin thus ... 

In the early versions, ethylene cyanohydrin was obtained from ethylene chlorohydrin and sodium cyanide. In later versions, ethylene oxide (from the dkect catalytic oxidation of ethylene) reacted with hydrogen cyanide in the presence of a base catalyst to give ethylene cyanohydrin. This was hydrolyzed and converted to acryhc acid and by-product ammonium acid sulfate by treatment with about 85% sulfuric acid. 

Ethylene glycol was originally commercially produced in the United States from ethylene chlorohydrin [107-07-3J, which was manufactured from ethylene and hypochlorous acid (eq. 8) (see Chlorohydrins). Chlorohydrin can be converted direcdy to ethylene glycol by hydrolysis with a base, generally caustic or caustic/bicarbonate mix (eq. 9). An alternative production method is converting chlorohydrin to ethylene oxide (eq. 10) with subsequent hydrolysis (eq. 11). 

Some substituted alkyl hydrogen sulfates are readily prepared. Eor example, 2-chloroethyl hydrogen sulfate [36168-93-1] is obtained by treating ethylene chlorohydrin with sulfuhc acid or amidosulfuhc acid. Heating hydroxy sulfates of amino alcohols produces the corresponding sulfuhc monoester... 

Where X is Br or Q, the free acids may be obtained by acidification of the alkaline solution, but where X is I, the acids must be isolated as salts to avoid reduction of the arsonic acids by HI. Rather than using alkyl haUdes, alkyl or dialkyl sulfates or alkyl arenesulfonates can be used. Primary alkyl haUdes react rapidly and smoothly, secondary haUdes react only slowly, whereas tertiary haUdes do not give arsonic acids. AHyl haUdes undergo the Meyer reaction, but vinyl hahdes do not. Substituted alkyl haUdes can be used eg, ethylene chlorohydrin gives 2-hydroxyethylarsonic acid [65423-87-2], C2H2ASO4. Arsinic acids, R2AsO(OH), are also readily prepared by substituting an alkaU metal arsonite, RAs(OM)2, for sodium arsenite ... 

Ethylene chlorohydrin [107-07-3J, HOCH2CH2CI, is the simplest chlorohydrin. It may also be called 2-chloroethanol, 2-chloroethyl alcohol, or glycol chlorohydrin. Ethylene chlorohydrin is ahquid at 15°C and 101.3 kPa (1 atm) (Table 1). This polar compound is miscible with water [7732-18-5] and ethanol [64-17-5] and is slightly soluble in ethyl ether [60-29-7] (5). 

Hydrolysis to Glycols. Ethylene chlorohydrin and propylene chlorohydrin may be hydrolyzed ia the presence of such bases as alkaU metal bicarbonates sodium hydroxide, and sodium carbonate (31—33). In water at 97°C, l-chloro-2-propanol forms acid, acetone, and propylene glycol [57-55-6] simultaneously the kinetics of production are first order ia each case, and the specific rate constants are nearly equal. The relative rates of solvolysis of... 

Esterification. Chlorohydrins can react with salts of carboxyUc acids to form esters. For example, 2-hydroxyethyl benzoate [134-11-2] was prepared ia 92% yield by heating sodium benzoate [532-32-1] with an excess of ethylene chlorohydrin ia the presence of a small amount of diethylamine... 

Etherification. A mixture of ethylene chlorohydrin ia 30% aqueous NaOH may be added to phenol at 100—110°C to give 2-phenoxyethanol [122-99-6] ia 98% yield (39). A cationic starch ether is made by reaction of a chlorohydfin-quaternary ammonium compound such as... 

Oxidation. Monochloroacetic acid [79-11-8] may be synthesized by the reaction of ethylene chlorohydrin with nitric acid [7697-37-2]. Yields of greater than 90% are reported (41). >Beta-chlorolactic acid (3-chloro-2-hydroxypropanoic acid) [1713-85-5] is produced by the reaction of nitric acid with glycerol monochlorohydrin (42). Periodic acid [10450-60-9] and glycerol monochlorohydfin gives chloroacetaldehyde [107-20-0] ia 50% yield (43). 

QuaterniZation. Choline chloride [67-48-1] was prepared ia nearly quantitative yield by the reaction of trimethylamine [121-44-8] with ethylene chlorohydrin at 90—105°C and 981—1471 kPa (10—15 kg/cm ) pressure (44). Precursors to quaternary ammonium amphoteric surfactants have been made by reaction of ethylene chlorohydrin with tertiary amines containing a long chain fatty acid group (45). 

For many years ethylene chlorohydrin was manufactured on a large iadustrial scale as a precursor to ethylene oxide, but this process has been almost completely displaced by the direct oxidation of ethylene to ethylene oxide over silver catalysts. However, siace other commercially important epoxides such as propylene oxide and epichlorohydrin cannot be made by direct oxidation of the parent olefin, chlorohydrin iatermediates are stiU important ia the manufacture of these products. 

The merchant market for chi orohydrin s is small, primarily for specialty appHcations. Ethylene chlorohydrin is sold ia the United States by BASF Corp., Parsippany, N.J., available ia 230 kg net lined steel dmms. Glycerol monochlorohydrin (3-chloro-l,2-propanediol) is available from Dixie Chemical Co., Houston, Tex., in lined steel dmms (227.3 kg net) from Raschig Corp., Richmond, Va. and from Henley Chemicals, Inc., Montvale, N.J., ia steel dmms (240 kg net). Glycerol dichi orohydrin (l,3-dichloro-2-propanol) is not currentiy being produced for the U.S. merchant market but has been available ia the past at a selling price of 5—6/kg. 

Toxicity of 2-Ghloroethanol. Ethylene chlorohydrin is an irritant and is toxic to the Hver, kidneys, and central nervous system. In addition, it is rapidly absorbed through the skin (73). The vapor is not sufficiently irritating to the eyes and respiratory mucous membranes to prevent serious systemic poisoning. Contact of the Hquid in the eyes of rabbits causes moderately severe injury, but in humans corneal bums have been known to heal within 48 hours. Several human fataUties have resulted from inhalation, dermal contact, or ingestion. One fatahty was caused by exposure to an estimated 300 ppm in air for 2.25 hours. In another fatal case, autopsy revealed pulmonary edema and damage to the Hver, kidneys, and brain (73). 

Ethylene chlorohydrin may be used in the manufacture of dye intermediates, pharmaceuticals, plant-protection agents, pesticides, and plastici2ers (3). 

Ethylene Chlorohydrin Technical BuUetiu, BASF Corp., Parsippany, N.J., 1989. 

An earlier procedure for the production of choline and its salts from natural sources, such as the hydrolysis of lecithin (23), has no present-day apphcation. Choline is made from the reaction of trimethyl amine with ethylene oxide [75-21-8] or ethylene chlorohydrin [107-07-5J. 

Like the formation of a-cyanohydrins, this reaction is catalyzed by bases or cyanide ion, but unlike the a-cyanohydrin case this reaction is not reversible, and under certain conditions it can proceed with violence. Ethylene cyanohydrin can also be prepared by the reaction of ethylene chlorohydrin and alkaH cyanides (39). 

Manufacture of alkylsulfones, important intermediates for metal-complex dyes and for reactive dyes, also depends on O-alkylation. An arylsulphinic acid in an aqueous alkaline medium is treated with an alkylating agent, eg, alkyl haUde or sulfate, by a procedure similar to that used for phenols. In the special case of P-hydroxyethylsulfones (precursors to vinylsulfone reactive dyes) the alkylating agent is ethylene oxide or ethylene chlorohydrin. 

Ethylene oxide [75-21-8] was first prepared in 1859 by Wurt2 from 2-chloroethanol (ethylene chlorohydrin) and aqueous potassium hydroxide (1). He later attempted to produce ethylene oxide by direct oxidation but did not succeed (2). Many other researchers were also unsuccesshil (3—6). In 1931, Lefort achieved direct oxidation of ethylene to ethylene oxide using a silver catalyst (7,8). Although early manufacture of ethylene oxide was accompHshed by the chlorohydrin process, the direct oxidation process has been used almost exclusively since 1940. Today about 9.6 x 10 t of ethylene oxide are produced each year worldwide. The primary use for ethylene oxide is in the manufacture of derivatives such as ethylene glycol, surfactants, and ethanolamines. 

With Acyl Halides, Hydrogen Halides, and Metallic Halides. Ethylene oxide reacts with acetyl chloride at slightly elevated temperatures in the presence of hydrogen chloride to give the acetate of ethylene chlorohydrin (70). Hydrogen haUdes react to form the corresponding halohydrins (71). Aqueous solutions of ethylene oxide and a metallic haUde can result in the precipitation of the metal hydroxide (72,73). The haUdes of aluminum, chromium, iron, thorium, and zinc in dilute solution react with ethylene oxide to form sols or gels of the metal oxide hydrates and ethylene halohydrin (74). 

Ethylene oxide has been produced commercially by two basic routes the ethylene chlorohydrin and direct oxidation processes. The chlorohydrin process was first iatroduced dufing World War I ia Germany by Badische Anilin-und Soda-Eabfik (BASE) and others (95). The process iavolves the reaction of ethylene with hypochlorous acid followed by dehydrochlofination of the resulting chlorohydrin with lime to produce ethylene oxide and calcium chloride. Union Carbide Corp. was the first to commercialize this process ia the United States ia 1925. The chlorohydrin process is not economically competitive, and was quickly replaced by the direct oxidation process as the dominant technology. At the present time, all the ethylene oxide production ia the world is achieved by the direct oxidation process. 

Chlorohydrin Process. Ethylene oxide is produced from ethylene chlorohydrin by dehydrochlorination using either sodium or calcium hydroxide (160). The by-products include calcium chloride, dichloroethane, bis(2-chloroethyl) ether, and acetaldehyde. Although the chlorohydrin process appears simpler, its capital costs are higher, largely due to material of constmction considerations (197). 

Dioxolanes haye been prepared from a carbonyl compound and an epoxide (e.g., ketone/SnC, CCI4, 20°, 4 h, 53% yield or aldehyde/ Et4N Br, 125-220°, 2-4 h, 20-85% yield ). Perhalo ketones can be protected by reaction with ethylene chlorohydrin under basic conditions (K2CO3, pentane, 25°, 2 h, 85% yield or NaOH, EtOH—H2O, 95% yield ). 

Diethylaminoethyl alcohol has been prepared by reduction of diethylaminoacetic ester with sodium and alcohol, by the action of ethylene chlorohydrin on diethylamine, and by the action of ethylene oxide on diethylamine. ... 

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