Acetic acid ethyl ester hydrolysis reaction

Dichloroacetic acid is produced in the laboratory by the reaction of chloral hydrate [302-17-0] with sodium cyanide (31). It has been manufactured by the chlorination of acetic and chloroacetic acids (32), reduction of trichloroacetic acid (33), hydrolysis of pentachloroethane [76-01-7] (34), and hydrolysis of dichloroacetyl chloride. Due to similar boiling points, the separation of dichloroacetic acid from chloroacetic acid is not practical by conventional distillation. However, this separation has been accompHshed by the addition of a eotropeforming hydrocarbons such as bromoben2ene (35) or by distillation of the methyl or ethyl ester. 

Hydrolysis of vinyl acetate is catalyzed by acidic and basic catalysts to form acetic acid and vinyl alcohol which rapidly tautomerizes to acetaldehyde. This rate of hydrolysis of vinyl acetate is 1000 times that of its saturated analogue, ethyl acetate, ia alkaline media (15). The rate of hydrolysis is minimal at pH 4.44 (16). Other chemical reactions which vinyl acetate may undergo are addition across the double bond, transesterification to other vinyl esters, and oxidation (15—21). 

The hydrolysis of ethyl acetate, prepared by the reaction of ethylene with acetic acid under pressure (154), and the hydrolysis of the ethyl ester of chlorosulfonic acid (155) have been considered and found to be of Httie industrial importance. 

Esters show similar behaviour. Hantzsch found the /-factor for ethyl acetate to be close to 2, and accurate determinations by Leisten also gave values close to 2 for ethyl and methyl benzoate and p-nitrobenzoate. In a solvent containing sufficient water, hydrolysis of the ester occurs. The reaction of methyl benzoate has a time of half-change of a few hours at 25°C in sulphuric acid containing about 0.07 M water, and Leisten actually used the increase in the / -factor, from 2 to 3, to follow the hydrolysis reaction, viz. 

The final increase in the rate of hydrolysis of the esters of primary aliphatic alcohols, in 85-100% H2SO, is presumably due to acyl-oxygen cleavage, since methyl acetate reacts faster than the ethyl ester, which would not be the case for alkyl-oxygen cleavage. So also may be the rapid hydrolysis of aryl acetates at moderate acidity, since aryl-oxygen cleavage is not expected to be so rapid a reaction. 

Reaction LXVII. (b) Acid Hydrolysis of Alkyl Derivatives of Ethyl Acetoacetate. (B., 19, 227.)—When acetoacetic ester or its mono- or di-alkyl derivatives are refluxed with concentrated aqueous or alcoholic potash, acid hydrolysis occurs and 2 mols. of acetic acid, or 1 mol. of that acid, and 1 mol. of a mono- or di-substituted derivative are obtained. 

Sulfanylalkanoyl amino acids and peptides are prepared by reaction of the (acetyl-sulfanyl)- or (benzoylsulfanyl)alkanoic acids or acid chlorides with a-amino esters or peptide esters, followed by deprotection of the sulfanyl and carboxy groups. 8 101114 16 27 29 For example, the 3-(acetylsulfanyl)alkanoic acids 7 are prepared from the condensation of ethyl (diethoxyphosphoryl) acetate 5 with various aldehydes according to the Horner-Emmons reaction, providing the a, 3-unsaturated ethyl esters 6 (a mixture of Z- and E-isomers, 50 50), followed by saponification of the ethyl esters and Michael addition of thiolacetic acid. The 3-(acetylsulfanyl)alkanoic acids 7 can be coupled with a-amino esters or peptide esters and subsequent hydrolysis of the 3-(acetylsulfanyl) derivatives provides the desired products 8 (Scheme 2). 14 ... 

A quantitative assessment of the effects of head group bulk on, S k2 and E2 reactions in cationic micelles has been made.148 The kinetics of the acid-catalysed hydrolysis of methyl acetate in the presence of cationic, anionic, and non-ionic surfactants has been reported on.149 The alkaline hydrolysis of -butyl acetate with cetyltrimethylammonium bromide has also been investigated.150 The alkaline hydrolysis of aromatic and aliphatic ethyl esters in anionic and non-ionic surfactants has been studied.151 Specific salting-in effects that lead to striking substrate selectivity were observed for the hydrolysis of /j-nitrophenyl alkanoates (185 n = 2-16) catalysed by the 4-(dialkylamino)pyridine-fimctionalized polymer (186) in aqueous Tris buffer solution at pH 8 and 30 °C. The formation of a reactive catalyst-substrate complex, (185)-(186), seems to be promoted by the presence of tris(hydroxymethyl)methylammonium ion.152... 

Interest in the kinetics of alkaline hydrolysis of esters in DMSO + water mixtures was stimulated by the observation that the rate constant often increased gradually as x2 increased. This is observed, for example, in the alkaline hydrolysis of ethyl acetate. For higher esters, e.g. ethyl p-nitrobenzoate, the rate constant drops slightly at low x2 but then rises again until k/k x2 = 0) > 1 (Tommila, 1964). The rate of alkaline hydrolysis of esters of benzoic acid is accelerated when DMSO is added (Tommila and Palenius, 1963), as also is the rate of alkaline hydrolysis of 2,4-dinitrofluorobenzene. In the latter case the effect is less dramatic because the rate constant for spontaneous hydrolysis also increases (Murto and Hiiro, 1964). The rate constants also increase when DMSO is added to aqueous solution for reactions between hydroxide ions and benzyl chloride (Tommila... 

Diacetyl Tartaric Acid Esters of Mono- and Diglycerides occur over a range in appearance from sticky, viscous liquids through a fatlike consistency to a waxy solid, depending on the iodine value of the oils or fats used in their manufacture. They are the reaction product of partial glycerides of edible oils, fats, or fat-forming fatty acids with diacetyl tartaric anhydride. The diacetyl tartaroyl esters are miscible in all proportions with oils and fats. They are soluble in most common fat solvents, in methanol, in acetone, and in ethyl acetate, but are insoluble in other alcohols, in acetic acid, and in water. They are dispersible in water and resistant to hydrolysis for moderate periods of time. The pH of a 3% dispersion in water is between 2 and 3. 

Acetals and ketals are readily prepared from carbonyl compounds and orthoformic esters in alcohol solution in the presence of a catalyst such as concentrated sulfuric acid, anhydrous hydrogen chloride, or ammonium chloride (60-95%)/ The reaction mixture must be neutralized before processing since the acetals are very sensitive to an acid hydrolysis. The methyl and ethyl esters of orthosilicic acid have been substituted for the ortfioformic esters with good results (70-90%) however, steps must be taken to remove compounds of silicon. ... 

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