Diethyl ether, hydrolysis

The determination of metal stearate lubricants by means of a hydrochloric acid/diethyl ether hydrolysis procedure has been described [2] and can be used if, for example, calcium or zinc stearate is known to be present. However, for... 

To a solution of 8 g of lithiim alanate in 250 ml of diethyl ether was added in 15 min 24 g (0.3 mol) of 2-penten-4-yn-l-ol (III, Exp. 57). The diethyl ether began to reflux and a rubber-like greyish precipitate was formed. After heating for 1 h under reflux the flask was placed in an ice + ice-water bath and water (150 ml) was added dropwise with vigorous stirring. After this hydrolysis procedure the ethereal solution was decanted and the aqueous jelly layer was extracted ten times with diethyl ether. The ethereal extracts were dried (without washing) over magnesium sulfate and subsequently concentrated in a water-pump vacuum. 

Lithium aluminum hydnde reacts violently with water and alcohols so it must be used m solvents such as anhydrous diethyl ether or tetrahydrofuran Following reduc tion a separate hydrolysis step is required to liberate the alcohol product... 

Barbier reported (1) in 1899 that a mixture of methyl iodide, a methyl ketone, and magnesium metal in diethyl ether produced a tertiary alcohol. Detailed studies by his student Victor Grignard are documented in his now classical doctoral thesis, presented in 1901. Grignard estabUshed (2) that the reaction observed by Barbier could be separated into three distinct steps Grignard reagent formation, Grignard reaction, and hydrolysis. 

Benzenepentol [4270-96-6] (pentahydroxybenzene) (74) has been prepared by boiling 2,4,6-ttiaminoresorciQol diethyl ether with water, followed by ether cleavage with HI (251). The product is very soluble ia water but spatingly soluble ia organic solvents. Benzenepentol prepared by hydrolysis of... 

Ethyl chloride can be dehydrochlorinated to ethylene using alcohoHc potash. Condensation of alcohol with ethyl chloride in this reaction also produces some diethyl ether. Heating to 625°C and subsequent contact with calcium oxide and water at 400—450°C gives ethyl alcohol as the chief product of decomposition. Ethyl chloride yields butane, ethylene, water, and a soHd of unknown composition when heated with metallic magnesium for about six hours in a sealed tube. Ethyl chloride forms regular crystals of a hydrate with water at 0°C (5). Dry ethyl chloride can be used in contact with most common metals in the absence of air up to 200°C. Its oxidation and hydrolysis are slow at ordinary temperatures. Ethyl chloride yields ethyl alcohol, acetaldehyde, and some ethylene in the presence of steam with various catalysts, eg, titanium dioxide and barium chloride. 

Diethyl ether is the principal by-product of the reaction of ethyl alcohol with diethyl sulfate. Various methods have been proposed to diminish its formation (70—72), including separation of diethyl sulfate from the reaction product. Diethyl sulfate not only causes an increase in ether formation but is also more difficult to hydroly2e to alcohol than is ethyl hydrogen sulfate. The equiUbrium constant for the hydrolysis of ethyl hydrogen sulfate is independent of temperature, and the reaction rate is proportional to the hydrogen ion concentration (73—75). 

The fluoride [NS(0)F]3 is more stable thermally and towards nucleophilic reagents than the corresponding chloride. For example, 8.15a is hydrolyzed by water to NH(S02NH2)2, whereas sulfanuric fluoride is unaffected by cold water. In warm water, however, hydrolysis occurs to give the [N3S304F2] anion. All three fluorine atoms in [NS(0)F]3 can be replaced by primary or secondary amines at 80-90°C in the absence of a solvent. Mono- or diphenyl derivatives can be prepared by treatment of [NS(0)F]3 with PhLi in diethyl ether at -70°C, while the Friedel-Crafts reaction with benzene at reflux in the presence of AICI3 gives two isomers of [NS(0)Ph]3. ... 

Arsine, AsHs, is formed when many As-containing compounds are reduced with nascent hydrogen and its decomposition on a heated glass surface to form a metallic mirror formed the basis of Marsh s test for the element. The low-temperature reduction of AsCls with LiAlH4 in diethyl ether solution gives good yields of the gas as does the dilute acid hydrolysis of many arsenides of electropositive elements (Na, Mg, Zn, etc.). Similar reactions yield stibine, e.g. ... 

In acid solution 1-acyl-1//-azepines and alkyl l//-azepine-l-carboxylates undergo rapid aromatization to A-arylcarbamates,115,139,142 whereas 1/Z-azepine-l-carbonitrile suffers quantitative rearrangement and hydrolysis to phenylurea.163 Rearrangement of ethyl l//-azepine-l-carboxylate to ethyl A-phenylcarbamate is also rapid (5 min) and quantitative with boron trifluoride-diethyl ether complex in benzene.245... 

In 1961, Roig and Dodson carried out a further study of the exchange in perchlorate media under identical conditions (25 °C, fi = 3.0 M) to those in the Tl(III) hydrolysis studyThe isotope was used, with a separation procedure based on extracting TI(III) from reaction mixtures with either methyl isobutyl ketone or diethyl ether. The exchange was examined in the absence of light, and a correction procedure to eliminate the catalytic effects of traces of chloride ions was used since Tl(III) concentrations of 10 M were necessary at the very low acidities employed. Using the known values of the first and second hydrolysis constants of Tl(III) (K2 and K3)... 

However, complete hydrolysis of carotenoid esters sometimes is not achieved in 1 to 3 hr. The saponification degree can be verified easily by the presence of carotenol ester peaks eluting later than the peaks of P-carotene on reversed phase columns. Retinol palmitate, added as an internal standard to orange juice, also serves to indicate whether saponification is complete, since it is converted to retinol which elutes at lower retention time. The mixture is subsequently washed with water until free of alkali in a separatory funnel. Other more polar solvents such as CH2CI2 or EtOAc, and diethyl ether alone or mixtured with petroleum ether can be used to increase the recovery of polar xanthophylls from the water phase. 

In the production of ethanol by the hydrolysis of ethylene, diethyl ether is produced as a by-product. A typical feed stream composition is 55 per cent ethylene, 5 per cent inerts, 40 per cent water and product stream 52.26 per cent ethylene, 5.49 per cent ethanol, 0.16 per cent ether, 36.81 per cent water, 5.28 per cent inerts. Calculate the yield of ethanol and ether based on ethylene. 

Methylcarborane [l-methyl-l,2-dicarbaclovododecaborane-(12)] may be prepared by hydrolysis of the Grignard reagent formed from the reaction of (bromomethyl)carborane with magnesium in the presence of diethyl ether.2c B h... 

Alkaline hydrolysis, in some cases carried out with the help of a microwave system, followed by extraction with organic solvents (normally w-hexane and diethyl ether), allows neutral and acidic compounds to be separated into two fractions, and the chromatographic data to be more easily interpreted. 

To remove excess CDI and reaction by-products, Beauchamp et al. (1983) dialyzed against water at 4°C. However, the imidazole carbamate groups on mPEG formed during the activation process are subject to hydrolysis in aqueous environments. A better method may be to precipitate the activated mPEG with diethyl ether as in the protocol described previously for SC activation (Section 1.2, this chapter). 

General Procedure for the Formation of Benzene Derivatives (see Eq. 2.48) At 0°C, dimethyl acetylenedicarboxylate (284 mg, 2 mmol) and CuCl (198 mg, 2 mmol) were added to a solution of zirconacyclopentadiene (1 mmol) in THF, prepared in situ according to the known procedure [12]. The reaction mixture was then allowed to warm to room temperature and was stirred for 1 h. After hydrolysis with 3 n HC1, the mixture was extracted with diethyl ether. The combined extracts were washed sequentially with water, aq. NaHC03 solution, brine, and water, and then dried over MgS04. Concentration in vacuo followed by flash-chromatography eluting with a mixture of hexane and diethyl ether (10 %) afforded benzene derivatives. 

An alternative procedure involves the release of the fatty acids by alkaline hydrolysis (saponification) by refluxing the extracted sample with dilute alcoholic potassium hydroxide for 1 h. After cooling, adding water and acidifying, the fatty acids are extracted into diethyl ether. The methyl esters can then be prepared by treatment with diazomethane, which may also be used directly on free fatty acids. Saponification is less satisfactory, because it is a lengthy procedure and often results in the loss of lipid components. 

The monomer silane diol (5) was prepared by hydrolysis of the bis-chlorosilane (4) in the presence of sodium hydrogenocarbonate NaHCO at reflux of diethyl ether for 24 h. The hydrolysis was quantitative. The silane diol (5) was characterized by IR, where a narrow band at 3690 cm and a wide band between 3650 and 3050 cm were observed, respectively, for free t)=siOHand bonded t)= aoH Us H- and F-NMR spectra exhibited the expected signals and its Si-NMR spectrum showed a singlet at -i-16.4ppm characteristic for a 5 = siOH and no trace of the starting chlorosilane at -i-31 ppm. ... 

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