Ethylene chlorohydrin, hydrolysis

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). 

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... 

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. 

I-Cyano-3-phenylurea, first obtained by the alkaline hydrolysis of 5-anilino-3- -toluyl-l,2,4-oxadiazole, has been prepared by tlic condensation of phenyl isocyanate and the sodium salt of cyanamide. However, in these publications an incorrect structural assignment for the product was made. 1-Cyano-3-phenyl-urea is obtained also, together with other products, by warming gently l-cyano-3-phenylthiourea with caustic soda in the presence of ethylene chlorohydrin, or by gradually adding caustic )otash to a boiling solution of 1-phenyldithiobiuret and ethylene clilorohydrin in ethanol. ... 

Chloroethyl benzoate has been prepared from benzoyl chloride and ethylene chlorohydrin from benzoic acid, ethylene glycol, and hydrogen chloride at 100° from ethylene oxide and benzoyl chloride from benzoyl chloride and dioxane in the presence of titanium tetrachloride from benzoic acid, ethylene, and chlorine in the presence of various catalysts. It has also been obtained by hydrolysis of 2-chloroethyl benzimidate " by the action of bromomagnesium benzoate on 2-chloroethyl -toluene-sulfonate and by the action of sodium benzoate on bis-(2-chloroethyl) sulfate. ... 

Ethylene adds hypochlorous acid more readily than it adds either moist chlorine or hydrogen chloride. Bubbled into chlorine water, it is converted completely into ethylene chlorohydrin, and by the hydrolysis of this substance glycol is obtained. Ethylene chlorohydrin is important also because of its reaction with ammonia whereby mono-, di-, and triethanolamine are formed, substances which are used in the arts and are not without interest for the explosives chemist. Ethylene may be oxidized catalytically in the gas phase to ethylene oxide which reacts with water to form glycol and with glycol to form diglycol which also is of interest to the dynamite maker. 

The more efficient route via cumene has superceded the fusion of benzene sulfonic acid with caustic soda for the manufacture of phenol, and the hydrolysis of chlorobenzene to phenol requires far more drastic conditions and is no longer competitive. Ethylene chlorohydrin can be hydrolyzed to glycol with aqueous sodium carbonate. 

Ethylene Glycols. Monoethylene glycol or ethylene glycol is the major derivative of ethylene oxide. Ethylene glycol was initially made commercially by hydrolysis of ethylene chlorohydrin. Today, hydrolysis of ethylene oxide is the preferred route. 

Hypochlorination of ethylene to ethylene-chlorohydrin, followed by hydrolysis with Na bi carbonate ... 

Phenylethyl alcohol is prepared by reduction of ethyl phenyl-acetate with sodium in absolute alcohol by hydrogenation of phenylacetaldehyde in the presence of a nickel catalyst or by addition of ethylene oxide or ethylene chlorohydrin to phenylmagnesium bromide, followed by hydrolysis. Phenylethyl alcohol also occurs naturally in a number of essential oils, especially rose oil. 

Properties Syrupy, colorless liquid characteristic odor. D 1.1852 (20C), bp 283C, fp -10C, viscosity 0.652 cP (20C), flash p 320F (160C), bulk d 9.85 lb/ gal, refr index 1.5217 (20C). Soluble in acetone, alcohol, chloroform, water slightly soluble in benzene, carbon tetrachloride, and ether. Combustible. Derivation Hydrolysis of dichloroethyl sulfide, interaction of ethylene chlorohydrin and sodium sulfide. 

The above hydrolysis reaction is suitably carried out in methanol, because under these conditions the target product is formed at 160°C in 8 hours in a yield of about 90%. The alkaline methanolic reaction mixture is then directly condensed with ethylene chlorohydrin, and in this case 2,4,S-trichloroanisol, formed during the reaction, also yields 2,4,5-TCP (Vasarhelyi et al., 1967). Solubility conditions of the organic components can be controlled by controlling the inorganic ion concentration of the condensation mixture, and thus secondary reactions can be suppressed (Vasarhelyi et al., 1968). 

Liquid, djj 1.0525. bp7w 109°, Quite stable to NaOH solns. Even dil acids produce hydrolysis to acetaldehyde and ethylene chlorohydrin [2-chloroet hanof). LDjq orally in rats 250 mg/kg, Smyth et al.. J. Ind. Hyg. Toxicol. 31, 60 (1949). 

The hydrolysis of the amyl chlorides with sodium oleate and caustic soda solution to form the corresponding alcohols is the basis of a flourishing industry and is discussed on another page. The ease of removal of halogen increases markedly from chlorine to iodine and with increasing complexity of the compound. Ethylene chlorohydrin, for example, is easily and smoothly hydrolyzed to ethylene glycol by aqueous sodium bicarbonate CH,0HCH,C1 + NaHCO, aq. - CH,OHCH,OH -H CO. + NaCl... 

Allyl chloride, crotyl chloride, and 1,3-dichloropropane show bimolecu-lar reactions with water and are 8x2 reactions. The effect of solvent is shown by the hydrolysis of benzyl chloride which is bimolecular in 50 per cent aqueous acetone and almost unimolecular in water. The formation of ethylene oxide from ethylene chlorohydrin is a reversible reaction ... 

Manufacture of Ethylene Glycol. Ethylene glycol can be made by the hydrolysis of ethylene chlorohydrin with sodium acid carbonate solution CH,OHCH,Cl -f NaHCO. - CH,OHCHjOH -I- NaCl + CO,... 

Ethylene chlorohydrin vapors form an explosive mixture with air the LEE and UEL values are 4.9% and 15.9% by volume of air, respectively. Among the hazardous reaction products are ethylene oxide, formed by internal displacement of the chlorine atom by the alkoxide ion, ethylene glycol formed by hydrolysis with sodium bicarbonate at 105°C (221°F), and ethylene cyanohydrin resulting from the reaction with alkali metal cyanides. 

The next major project for the Industrial Testing Laboratory was an attempt to improve the process of making ethylene glycol from ethylene via the hydrolysis of ethylene chlorohydrin. In his attempt to produce this "anti-freeze" by hydrolysis of ethylene dichloride with sodium polysulfide, "Doc" Patrick obtained a gummy gunk which he named "Thiokol" based on the greek word theion (sulfur) and kommi (gum). 

Grunwald-Winstein analyses of kinetic results have proved less successful for the two-stage mercury(ii)-catalysed aquation of the [RuCl(NH3)6] + cation, for associative attack of cyanide at the [Fe(bipy)a] cation, and for aquation of the [Fe(phen)a] + cation. Logarithms of rates of isomerization of trans-[Cr(ox) -(0112)2] correlate better with logarithms of rates of base hydrolysis of ethylene chlorohydrin than with solvent Y values (i.e. than with logarithms of rates of t-butyl chloride solvolysis). ... 

Benzyl chloride readily forms a Grignard compound by reaction with magnesium in ether with the concomitant formation of substantial coupling product, 1,2-diphenylethane [103-29-7]. Benzyl chloride is oxidized first to benzaldehyde [100-52-7] and then to benzoic acid. Nitric acid oxidizes directly to benzoic acid [65-85-0]. Reaction with ethylene oxide produces the benzyl chlorohydrin ether, CgH CH20CH2CH2Cl (18). Benzylphosphonic acid [10542-07-1] is formed from the reaction of benzyl chloride and triethyl phosphite followed by hydrolysis (19). 

Merck and Maeder have patented the manufacture of arecaidine by loss of water from l-methyl-4-hydroxypiperidine-3-carboxylic acid. A method of producing the latter has been describd by Mannich and Veit and has been developed by Ugriumov for the production of arecaidine and arecoline. With the same objective, Dankova, Sidorova and Preobrachenski use what is substantially McElvain s process,but start by converting ethylene oxide, via the chlorohydrin and the cyanohydrin, into -chloropropionic acid. The ethyl ester of this with methylamine in benzene at 140° furnishes methylbis(2-carbethoxyethyl) amine (I) which on refluxing with sodium or sodium Moamyloxide in xylene yields l-methyl-3-carbethoxy-4-piperidone (II). The latter is reduced by sodium amalgam in dilute hydrochloric acid at 0° to l-methyl-3-carbethoxy-4-hydroxypiperidine (III) which on dehydration, and hydrolysis, yields arecaidine (IV R = H), convertible by methylation into arecoline (IV R = CH3). 

J-Chloropropionic acid has been prepared by the hydrolysis of ethylene cyanohydrin with hydrochloric acid,1 and by the oxidation of /S-chloropropionaldehyde2 or of trimethylene chlorohydrin 3 by nitric acid. 

Further evidence for heterolytic decomposition is obtained from the effect of olefin structure on product distribution. Table II shows the ratio of carbonyl to glycol product for three olefins. Listed for comparison is the carbonyl/glycol ratio for the chlorohydrin, which corresponds to the structure of the oxythallation adduct from ethylene and propylene. The effect of structure on the ratio is qualitatively the same for the thallic ion oxidation and the hydrolysis of the corresponding chlorohydrin. Since the product distributions for both are inconsistent with neighboring hydroxyl participation (Reaction 33) the carbonyl/glycol ratio is a measure of the competition between hydride shift vs. water attack in... 

Hypo chlorination of ethylene to erhylene-chlorohydrin, followed by hydrolysis widi Na bicarbonate. ... 

Forsberg, G., Rate constants and reaction products of the alkaline hydrolysis of ethylene and trimethylene chlorohydrins with alkyl substituents, Acto Chem. Scand. 8 (1), 135, 1954. 

A differentiation should be made between the hydrolysis of simple halogen compounds and chlorohydrins, since a difference in reaction mechanism, and in many cases a difference in order of magnitude of yield, is involved. Ethylene oxide is considered to be an intermediate between ethylene ( orohydrin and ethylene glycol The aromatic halides are much more difficult to hydrolyze. Acids are without effect upon them, save in the... 

This method can be used, after hydrolysis, for the determination of ethylene znd propylene chlorohydrine. ... 

Since they are efficient alkylating agents, the pure compounds are very toxic. After application, all the residual amounts must be completely removed. The glycols resulting from their hydrolysis are not as toxic (ethylene glycol LD50 for rats is 8.3g/kg body weight). Toxic reaction products can be formed, as exemplified by chlorohydrin obtained in the presence of chloride ... 

Oxiranes are highly toxic alkylating agents and the hydrolysis product of ethylene oxide ethylene glycol and reaction products of oxiranes with chloride ions is likewise toxic. The latter reaction yields 2-chloroethanol, which arises from oxirane, and isomeric vicinal chloropropanols (chlorohydrins) resulting from methyloxirane (Figure 11.3). Oxiranes react with a number of other food components, such as vitamins (riboflavin, pyridoxine, niacin and folic acid) or amino acids (methionine and histidine) to form biologically inactive products. 

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