Ethanol anhydrous

Now, the ethanol used is almost always anhydrous, meaning it has no water. The closest one can get commercially to anhydrous ethanol is Everclear which is 95% ethanol and 5% water (190 proof). A lot of chemical supply stores will not carry 100% (200 proo ethanol because it is a potable (drinkable) product. This means that they would have to get a liquor license or some other state permit to sell the stuff and that is a hassle that many don t want to bother with,... 

Fig. 20. Energy inputs and outputs to manufacture 3.785 L of anhydrous ethanol from com. (-) denotes system boundary. AH KJ figures are lower...

Fig. 9. Extractive distillation sequence cost as a function of the feed ratio for the production of anhydrous ethanol from azeotropic ethanol using ethylene glvcol at reflux ratios of A, 1.15 r O, 1.2 r and 1.3 r (39). Point A represents a previously pubhshed design for the same mixture (37).

The hquid product streams are fed to a distillation system to remove the light impurities and to recover the ethanol as a 95% volume ethanol—water a2eotrope. To produce anhydrous ethanol, the ethanol—water a2eotrope is fed to a dehydration system. 

Hydrogenation of Acetaldehyde. Acetaldehyde made from acetylene can be hydrogenated to ethanol with the aid of a supported nickel catalyst at 150°C (156). A large excess of hydrogen containing 0.3% of oxygen is recommended to reduce the formation of ethyl ether. Anhydrous ethanol has also been made by hydrogenating acetaldehyde over a copper-on-pumice catalyst (157). 

All containers must be absolutely dry, and anhydrous xylene must be used. Important Destroy with anhydrous ethanol all potassium remaining in the xylene and waste ether. 

Ethanol [64-17-5] M 46.1, b 78.3 , d 0.79360, d 0.78506, n 1.36139, pK 15.93. Usual impurities of fermentation alcohol are fusel oils (mainly higher alcohols, especially pentanols), aldehydes, esters, ketones and water. With synthetic alcohol, likely impurities are water, aldehydes, aliphatic esters, acetone and diethyl ether. Traces of benzene are present in ethanol that has been dehydrated by azeotropic distillation with benzene. Anhydrous ethanol is very hygroscopic. Water (down to 0.05%) can be detected by formation of a voluminous ppte when aluminium ethoxide in benzene is added to a test portion. Rectified... 

Commercial anhydrous ethanol was used throughout without further purification. 

The lithium ethoxide solution is prepared by dissolving f.40 g. of lithium wire in 1 1. of anhydrous ethanol. 

Estrone methyl ether (100 g, 0.35 mole) is mixed with 100 ml of absolute ethanol, 100 ml of benzene and 200 ml of triethyl orthoformate. Concentrated sulfuric acid (1.55 ml) is added and the mixture is stirred at room temperature for 2 hr. The mixture is then made alkaline by the addition of excess tetra-methylguanidine (ca. 4 ml) and the organic solvents are removed. The residue is dissolved in heptane and the solution is filtered through Celite to prevent emulsions in the following extraction. The solution is then washed threetimes with 500 ml of 10 % sodium hydroxide solution in methanol to remove excess triethyl orthoformate, which would interfere with the Birch reduction solvent system. The heptane solution is dried over sodium sulfate and the solvent is removed. The residue is satisfactory for the Birch reduction step. Infrared analysis shows that the material contains 1.3-1.5% of estrone methyl ether. The pure ketal may be obtained by crystallization from anhydrous ethanol, mp 99-100°. Acidification of the methanolic sodium hydroxide washes affords 10-12 g of recovered estrone methyl ether. 

Preparation of l9-Norandrost-A-ene-3, l-dionef A solution of 1.1 g of 10y5-cyano-19-norandrost-5-ene-3,17-dione bis-ethylene ketal in a mixture of 15 ml of ethanol and 15 ml of toluene is carefully added to a vigorously stirred suspension of 10 g of sodium in 150 ml of boiling toluene. The addition is regulated to maintain the reaction mixture at the boiling point of the solvent. Another 40 ml of anhydrous ethanol is then added at the same rate. The solution is cooled and the excess of sodium is decomposed by addition of 95% ethanol. The reaction mixture is then diluted with water, the toluene layer separated and the aqueous phase extracted twice with ether. The organic solution is washed with water, dried and evaporated to yield 1 g of an amorphous mixture of the bis-ethylene ketals of 19- norahd-rost-5- and -5(10)-ene-3,17-dione (Note 1). 

The sodium or potassium salt of 6-azauracil in aqueous ethanol, anhydrous ethanol, or ethylene glycol reacted with methyl iodide practically exclusively to give the 3-methyl derivative (63). In toluene the sodium, potassium, and mercuric salts produced no methylated derivatives whereas the silver salt also yielded the 3-methyl derivative, Similarly, the 3-methyl derivative was prepared from the mercuric salt of 6-azathymine, and its structure was established by hydrolysis to pyruvic acid 4-methylthiosemicarbazone. ... 

A mixture of 7.8 grams (0.05 mol) of )3-(p-aminophenyl)ethyl chloride hydrochloride, 12.5 grams (0.025 mol) of 4-phenyl-4-carboethoxypiperidine carbonate, 10.5 grams (0.125 mol) sodium bicarbonate, and 100 cc of anhydrous ethanol are mixed, stirred and heated under reflux for a period of approximately 40 hours and then concentrated in vacuo to dryness. The residual material is triturated with 50 cc of water, decanted, washed by decantation with an additional 50 cc of water, and then dried in vacuo to give N-[)3-(p-aminophenyl)-ethyl] -4-phenyl-4-carboethoxypiperidine. 

The N-[)3-(p-aminophenyl)ethyl]-4-phenyl-4-carboethoxypiperidine is dissolved in 50 cc of hot anhydrous ethanol, an excess (about 20 cc) of 20% alcoholic hydrochloric acid solution is added upon scratching the side of the container crystals form. One hundred cubic centimeters of ether are then added to the mixture, the ethereal mixture is cooled, and the crystalline material which precipitates is recovered by filtration, washed with ether, and dried to give 12.7 grams of N-[)3-(p-aminophenyl)ethyl]-4-phenyl-4-carboethoxypiperidine dihydrochloride which can be further purified by recrystallization from ethanol or methanol to give substantially pure material MP 275°-277°C. 

The N-[/3-(o-chlorophenyl)-/3-hydroxyethyl] -isopropylamine obtained by the foregoing procedure was dissolved in about 3 liters of ether and dry hydrogen chloride gas was bubbled into the solution until it was saturated, whereupon the hydrochloride salt of N-[/3-(o-chloro-phenyl)-/3-(hydroxy)-ethyl] isopropylamine precipitated. The salt was separated from the ether by filtration, and was dissolved in two liters of anhydrous ethanol. The alcoholic solution was decolorized with charcoal and filtered. 

The ether is left to stand at a low temperature below 10°C when the remaining portion of the product precipitates and is filtered off and added to the first precipitate. The product thus obtained is thoroughly washed, first in water and then in a solution of sodium bicarbonate, and then agein in water. After drying in air, the product is crystallized from anhydrous ethanol or from acetone and water. The analytical data correspond to calculated values. Yield is 18 g MP 122°Cto 124°C. 

On the addition of ethereal hydrogen chloride to a solution of the base in isopropanol and recrystallization from anhydrous ethanol of the salt formed, there is obtained 3-dimethyl-sulfamovl-10-(2-dimethvlaminopropyl)phenthiazine hydrochloride (2.1 grams), MP 214°C with decomposition. After dissolving the product in anhydrous ethanol and adding meth-anesulfonic acid there is obtained fonazine mesylate. 

To a suspension containing 4.86 parts of 4-methylbenzenesulfonyl urethane (MP 80° to 82°C) and 36 parts of anhydrous toluene there are rapidly added 2.5 parts of N-amino-3-azabicyclo(3.3.0)octane (BP/18 mm = 86°C). The reaction mixture is heated under reflux for 1 hour. The resulting ciear solution crystallizes on cooling. The crystals are filtered, washed with 2 parts of toluene, then recrystallized from anhydrous ethanol. There are obtained 3.8 parts of the desired product, MP 180° to 182°C. 

In an initial step, the sodium derivative of ethyl (3-benzoylphenyl)cyanoecetate is prepared as follows (3-benzoylphenyl)acetonitrile (170 g) is dissolved in ethyl carbonate (900 g). There is added, over a period of 2 hours, a sodium ethoxide solution [prepared from sodium (17.7 g) and anhydrous ethanol (400 cc)], the reaction mixture being heated at... 

Then, ethyl methyl(3-benzoylphenyl)cyanoacetate employed as an intermediate material is prepared as follows The sodium derivative of ethyl (3-benzoylphenyl)cyanoacetate (131 g) is dissolved in anhydrous ethanol (2 liters). Methyl iodide (236 g) is added and the mixture is heated under reflux for 22 hours, and then concentrated to dryness under reduced pressure (10 mm Hg). The residue is taken up in methylene chloride (900 cc) and water (500 cc) and acidified with 4N hydrochloric acid (10 cc). The methylene chloride solution is decanted, washed with water (400 cc) and dried over anhydrous sodium sulfate. The methylene chloride solution is filtered through a column containing alumina (1,500 g). Elution is effected with methylene chloride (6 liters), and the solvent is evaporated under reduced pressure (10 mm Hg) to give ethyl methyl(3-benzoylphenyl)cyano-acetate (48 g) in the form of an oil. 

A mixture of 23.8 grams (0.2 mol) of propargyl bromide, 24.2 grams (0.2 mol) of N-methyl benzylamine and 400 ml of anhydrous ethanol in the presence of 42.4 grams (0.4 mol) of anhydrous sodium carbonate was heated at the boiling temperature and under reflux for a period of 17 hours. 

Methyl ethyl (7-methoxy-10-methyl-3-phenthiazinyl)malonate is prepared by reacting a solution of sodium (4.37 grams) in anhydrous ethanol (110 cc) with a solution of methyl (7-methoxy-10-methyl-3-phenthiazinyl)acetate (59 grams) in ethyl carbonate (180 cc). 

Methyl ethyl (7-methoxy-10-methyl-3-phenthiazinyl)malonate (62.2 grams) followed by methyl iodide (45.7 grams) is added to a solution of sodium (4.45 grams) in anhydrous ethanol (500 cc). The reaction mixture is heated under reflux for 1 hour at 45°C, then for 6 hours at 55°C, and finally concentrated to dryness under reduced pressure (20 mm Hg). The residue is taken up in methylene chloride (300 cc) and water (250 cc), filtered in the presence of a filtration adjuvant, washed with methylene chloride (150 cc) and water (150 cc), and decanted. The aqueous solution is extracted once again with methylene chloride (100 cc), and the combined organic solutions washed with water (100 cc), aqueous 0.1 N sodium hyposulfite solution (200 cc) and finally with water (200 cc). After drying over anhydrous sodium sulfate and evaporation to dryness under reduced pressure (20 mm Hg), there is obtained an oil (64.8 grams) which is dissolved in methylene chloride (100 cc) and... 

The following is an alternate method of preparation A mixture of 3-(1-piperazinyl)car-bonylmethyl-5-chloro-2(3H)-benzothiazolinone (500 mg), anhydrous potassium carbonate (400 mg), 2-hydroxyethyl bromide (300 mg) and anhydrous ethanol (20 ml) is heated while refluxing for 5 hours. The reaction mixture is concentrated under reduced pressure. The residue is extracted with chloroform. The chloroform layer is dried over magnesium... 

In a 1-1. round-bottomed flask equipped with a condenser are placed 78.0 g. (0.56 mole) of commercial anhydrous potassium arbonate, 45.0 g. (0.50 mole) of methallyl chloride (Note 1), 55.0 g. (0.55 mole) of 2,4-pentanedione (Note 1), and 300 ml. of anhydrous ethanol (Note 2). The mixture is refluxed on a steam bath for 16 hours. The condenser is replaced by a distilling head and condenser, and about 200 ml. of ethanol is distilled from the mixture (Note 3). Ice water (600 ml.) is added to dissolve the salts, and the mixture is extracted three times with ether. The... 

Ten grams (0.082 mole) of benzoic acid is added to 100 ml. of anhydrous ethanol in a 2-1. three-necked flask equipped with a mechanical stirrer and with loose cotton plugs in the side necks. After the benzoic acid has dissolved, 600 ml. of liquid ammonia (Note 1) is added to the stirred solution. Then 6.2 g. (0.27 g. atom) of sodium is added in small pieces. When about one-third of the sodium has been added, the white sodium salt of the acid precipitates, and there is strong foaming of the reaction mixture. After all the sodium has been consumed, as evidenced by the disappearance of the blue color, 14.6 g. (0.27 mole) of ammonium chloride is added cautiously. The mixture is stirred for an additional hour and then allowed to stand until the ammonia has evaporated. 

The reaction at Eq. (12) allows the preparation of Na2S4 and K2S5 from the alkali metals, hydrogen sulfide and sulfur in anhydrous ethanol (ROH). First the metal is dissolved in the alcohol with formation of ethanolate (MOR) and hydrogen. Bubbling of H2S into this solution produces the hydrogen sulfide (MHS). To obtain the polysulfide the solution is refluxed with the calculated amount of elemental sulfur. After partial evaporation of the solvent and subsequent cooling the product precipitates. 

Note It is reported that the use of chlorobenzene as solvent is essential when the reagent is to be used to detect aromatic amines [1]. In the case of steroids, penicillins, diuretics and alkaloids the reaction should be accelerated and intensified by spraying afterwards with dimethylsulfoxide (DMSO) or dimethylformamide (DMF), indeed this step makes it possible to detect some substances when this would not otherwise be possible [5,9-11] this latter treatment can, like heating, cause color changes [5,9]. Penicillins and diuretics only exhibit weak reactions if not treated afterwards with DMF [10, 11]. Steroids alone also yield colored derivatives with DMSO [9]. Tlreatment afterwards with diluted sulfuric acid (c = 2 mol/L) also leads to an improvement in detection sensitivity in the case of a range of alkaloids. In the case of pyrrolizidine alkaloids it is possible to use o-chloranil as an alternative detection reagent however, in this case it is recommended that the plate be treated afterwards with a solution of 2 g 4-(dimethyl-amino)-benzaldehyde and 2 ml boron trifluoride etherate in 100 ml anhydrous ethanol because otherwise the colors initially produced with o-chloranil rapidly fade [12]. 

Because of certain misconceptions with regard to the choice of solvent and the occurrence of sulfur-oxygen bond fission in hydroxylic solvents - , it is important to emphasize that one can greatly reduce the rate of this competing process by the use of weak bases. In systems which can undergo facile C—O as well as S—O bond fission, it is possible to control the type of bond cleavage by choosing the appropriate base . A remarkable illustration of this behavior is found in the ethanolysis of sulfinate 6a. In anhydrous ethanol at 90.0° with acetate ion as the added base, 6a yielded ethyl 2, 6-dimethylbenzenesulfinate plus a trace of sulfone 7a. Under the same conditions but with 2,6-lutidine the reaction was slower and sulfone 7a was the only detectable reaction product . ... 

The spiroindolinobenzopyran 2 is a classical example of spiropyran and is easily prepared by the condensation of l,3,3-trimethyl-2-methyleneindo-line (Fischer s base) and salicylaldehyde in anhydrous ethanol or benzene (Scheme 2).ia The nucleophilic attack of Fischer s base on the carbonyl group (like an enamine) gives an aldol product, which undergoes ring closure followed by dehydration. This condensation is reversible therefore, an exchange of the salicylaldehyde component of spiropyran with a different salicylaldehyde is possible. For example, when a solution of spiropyran 2 (Scheme 2) was refluxed with 3,5-dinitro-substituted salicylaldehyde, the open form of 6,8-dinitro-BIPS was obtained.2... 

Materials and Purification. Chemicals were purchased from Aldrich chemical company and used as received unless otherwise noted 1,1,1,3,3,3-hexamethyl disilazane, ethylene glycol, triphosgene, poly(ethylene oxide) (MW = 600), poly(tetramethylene oxide) (MW = 1000), poly(caprolactonediol) (MW = 530), toluene diisocyanate (TDI), anhydrous ethanol (Barker Analyzed), L-lysine monohydride (Sigma) and methylene bis-4-phenyl isocyanate (MDI) (Kodak). Ethyl ether (Barker Analyzer), triethylamine and dimethyl acetamide were respectively dried with sodium, calcium hydride and barium oxide overnight, and then distilled. Thionyl chloride and diethylphosphite were distilled before use. 

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