Ethers ordinary

The ethers are compounds obtained by condensation of alcohols, with elimination of water. The most important ether is diethyl ether (ordinary ether), (C2H5) 20. It is made by treating ethanol with concentrated sulfuric acid, which serves as a dehydrating agent ... 

Pour the reaction mixture into a 250-mL Erlenmeyer flask containing 50 mL of 10% sulfuric acid and about 25 g of ice and use both ordinary ether and 10% sulfuric acid to rinse the flask. Swirl well to promote hydrolysis of the addition compound basic magnesium salts are converted into water-soluble neutral salts and triphenylmethanol is distributed into the ether layer. An additional amount of ether (ordinary) may be required. Pour the mixture into a separatory funnel (rinse the flask with ether), shake, and draw off the aqueous layer. Shake the ether solution with 10% sulfuric acid to further remove magnesium salts, and wash with saturated sodium chloride solution to remove water that has dissolved in the ether. The amounts of liquid used in these washing operations are not critical. In general, an amount of wash liquid equal to one-third of the ether volume is adequate. 

To Purli Ether. Ordinary ether is purified by first agitatingit with 2 or 3 times its volume of distilled water containing a few grains of carbonate of potassa, or a few drops of milk of lime and, er decantation, again agitated with a like quantity of water only. This may be used for inhalations. The washed ether is afterwards digested on chloride of calcium to deprive it of retained moisture. 

Diethyl Ether (Ordinary ether, sutjJmrie ether, yl ether, diethyl oxide)... 

In an experiment, a slight excess of the hydride is employed to ensure the complete reduction the unused hydride must then be destroyed. This can be done by the cautious addition of (rt) water, or (6) ordinary undried ether, which will ensure that the supply of water is both small and gradual, or (c) an ester such as ethyl acetate, which will be reduced to ethanol. The first of these methods, namely the addition of water, is hazardous and should be avoided. 

Now cool the mixture thoroughly in ice-water, and run in over a period of 45 minutes a solution of 6 o g. of dry salicylic acid in 75 ml. of dry ether. When the addition of the acid to the stirred solution is complete, heat the mixture under reflux on the water-bath for 15 minutes to ensure completion of the reduction. Then thoroughly chill the mixture in ice-water, and hydrolyse any unused hydride by the slow addition of 50 ml. of ordinary undried ether, followed similarly by 75 ml. of dilute sulphuric acid. 

Preparation of REAOENTS.t It is essential for this preparation that the zinc powder should be in an active condition. For this purpose, it is usually sufficient if a sample of ordinary technical zinc powder is vigorously shaken in a flask with pure ether, and then filtered off at the pump, washed once with ether, quickly drained and without delay transferred to a vacuum desiccator. If, however, an impure sample of zinc dust fails to respond to this treatment, it should be vigorously stirred in a beaker with 5% aqueous sodium hydroxide solution until an effervescence of hydrogen occurs, and then filtered at the pump, washed thoroughly with distilled water, and then rapidly with ethanol and ether, and dried as before in a vacuum desiccator. The ethyl bromoacetate (b.p. 159 ) and the benzaldehyde (b.p. 179 ) should be dried and distilled before use. 

To obtain crystalline perbenzoic acid, dry the moist chloroform solution with a little anhydrous sodium or magnesium sulphate for an hour, filter, and wash the desiccant with a little dry chloroform. Remove the chloroform under reduced pressure at the ordinary temperature whilst carbon dioxide is introduced through a capillary tube. Dry the white or pale yellow residue for several hours at 30-35° under 10 mm. pressure. The yield of crystalline perbenzoic acid, m.p. about 42°, which is contaminated with a little benzoic acid, is 22 g. It is moderately stable when kept in the dark in a cold place it is very soluble in chloroform, ethyl acetate and ether, but only shghtly soluble in cold water and in cold hght petroleum. 

Aromatic alcohols are insoluble in water and usually burn with a smoky flame. Their boiling points are comparatively high some are solids at the ordinary temperature. Many may be oxidised by cautious addi-tion of dilute nitric acid to the corresponding aldehyde upon neutralis-tion of the excess of acid, the aldehyde may be isolated by ether extraction or steam distillation, and then identified as detailed under Aromatic Aldehydes, Section IV,135. 

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. 

After all of the cyclohexylbromopropene has been run in, heating is continued for about two hours, the mixture is cooled and 500 cc. of ether is added. This mixture is poured on 1.5 kg. of cracked ice in a 5-I. flask and then acidified with 280 cc. of concentrated hydrochloric acid. The ether layer is separated, dried over calcium chloride and transferred to a i-l. modified Claisen flask (Org. Syn. 1, 40) for distillation. The ether is distilled at ordinary pressure and then the cyclohexylpropine under diminished pressure. The product boiling up to ii5°/2o... 

Azobenzene [103-33-3] M 182.2, m 68", pK 2.48. Ordinary azobenzene is nearly all in the transform. It is partly converted into the cw-form on exposure to light [for isolation see Hartley J Chem Soc 633 1938, and for spectra of cis- and /ran5-azobenzenes, see Winkel and Siebert Chem Ber 74B 6707947]. trans-Azobenzene is obtained by chromatography on alumina using 1 4 benzene/heptane or pet ether, and crystd from EtOH (after refluxing for several hours) or hexane. All operations should be carried out in diffuse red light or in the dark. 

When just a trace of dark impurity is present, as in some of the commercial preparations, a completely pure product is easily obtained by vacuum distillation, but the ordinary crude reaction product is likely to decompose when treated in this manner. The ether method introduced in the present procedure has the advantage of being simple and efficient. It is equally applicable to the purification of the homologues of a-naphthoquinone. 

The residual crude cyanamide remaining after evaporation of the ethereal extracts (which need not be dried previously) is dissolved readily in the appropriate volume of cold water. A small quantity of water-insoluble oily or semisolid by-products is removed by shaking the solution with carbon and filtering the liquid through a small ordinary filter, followed by rinsing with a few milliliters of water. The clear filtrate is suitable for the subsequent operation. 

The 2-cyclohexenone obtained by an ordinary distillation at this point is contaminated with lower-boiling impurities (see Note 5), primarily ether and ethanol. 

The equivalent charge weight of TNT is calculated on the basis of the entire cloud content. FMRC recommends that a material-dependent yield factor be applied. Three types of material are distinguished Class I (relatively nonreactive materials such as propane, butane, and ordinary flammable liquids) Class II (moderately reactive materials such as ethylene, diethyl ether, and acrolein) and Class III (highly reactive materials such as acetylene). These classes were developed based on the work of Lewis (1980). Energy-based TNT equivalencies assigned to these classes are as follows ... 

Properties.—Colourless, mobile liquid b.p. 35° sp. gr. 0720 at 15 burns with a luminous flame not miscible with water 9 parts of water dissolve i part of ether, and 35 parts of ether dissolve i part of water at the ordinary temperature. See Appoidix p. 236. 

Properties.—A viscid, colourless liquid, with a sweet taste m.p. 17°, b. p. 290°. It boils, under ordinary pressure. with partial decomposition forming acrolein sp gr. radp at 12° miscible with w ater and alcohol Insoluble in ether and the hydrocarbons. 

Properties.—Colourless needles, with a characteristic smell m. p. 42—43 b. p. 182° easily soluble in alcohol and ether and in about 15 parts of water at the ordinary temperature produces blisters on the skin. 

The fi-compound is dissolved in 50 c c. pure dry ether, and dry hydiogen chloride is passed in with constant shaking to prevent the delivery tube from becoming blocked. Colourless crystals of the hydrochloride of the /3-o ime separate and aie filtered and washed with dry ether and then placed in a separating funnel and covered with a layer of ether. A. concentrated solution of sodium carbonate is gradually added with constant shaking until no further effervescence is observed. Sodium chloride is precipitated and the /3-oxime dissolves in the ether. The ether extract is sepaiated, dehydrated over sodium sulphate, and the ether remoi ed as rapidly as possible at the ordinary temperature by evaporation in vacuo. The residue crystallises, and when pressed on a porous plate leaves a mass of small silky needles, m. p. 126—130A It may be re-... 

Two different alkenes can be brought to reaction to give a [2 -I- 2] cycloaddition product. If one of the reactants is an o, /3-unsaturated ketone 11, this will be easier to bring to an excited state than an ordinary alkene or an enol ether e.g. 12. Consequently the excited carbonyl compound reacts with the ground state enol ether. By a competing reaction pathway, the Patemo-Buchi reaction of the 0, /3-unsaturated ketone may lead to formation of an oxetane, which however shall not be taken into account here ... 

WojQo 1-4652) in absolute ethereal solution was allowed to react with palladium black. After a few hours hydrogen was passed into the liquid at ordinary temperature, giving rise to a terpene possessing the following... 

The fraction of opoponax oil boiling at 135° to 137° in vacuo contains a sesquiterpene, which has been examined by Schimmel Co. On fractionation at ordinary pressure, it boiled at about 260° to 270°, and in this impure condition was dissolved in ether and saturated with hydrochloric acid gas. The crystalline hydrochloride which resulted melted at 80°, and was optically inactive. It has the composition. 3HC1. 

It yields a well-defined phenyl-urethane, melting at 113°. It requires considerable care to obtain this compound, which should be prepared as follows terpineol mixed with the theoretical amount of phenyl-isocyanate is left for four days at the ordinary room temperature. Crystals separate which are diphenyl urea,, and are removed by treating the product with anhydrous ether, in which the diphenyl urea is insoluble. If the liquid be very carefully and slowly evaporated fine needles of terpinyl-phenyl urethane separate. This compound has the formula C Hj. NH. COOCjqHj-. The correspnanding naphthyl-urethane melts at 147° to 148°. 

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