Methyl alcohol purification

Absolute methyl alcohol. The synthetic methanol now available is suitable for most purposes without purification indeed, some manufacturers claim a purity of 99 85 per cent, with not more than 0 1 per cent, by weight of water and not more than 0 02 per cent, by weight of acetone. Frequently, however, the acetone content may be as high as 0 1 per cent, and the water content 0-5-1 per cent. 

The total yield amounts to 260-266 g. (48.5-49.5 per cent of the theoretical amount). The product is contaminated by slight traces of d-glucose and possesses a very faint reducing power towards Fehling s solution. For complete purification it is recrystallized (with practically no loss and practically no change in melting point) from five parts of methyl alcohol with the use, if necessary, of decolorizing carbon. 

Methylated spirit contains, in addition to ethyl and methyl alcohols, water, fusel-oil, acetaldehyde, and acetone. It may be freed from aldehyde by boiling with a—3 per cent, solid caustic potash on the water-bath with an upright condenser for one hour, or if larger quantities are employed, a tin bottle is preferable, which is heated directly over a small flame (see Fig. 38). It is then distilled with the apparatus shown in Fig. 39. The bottle is here surmounted with a T-piece holding a thermometer. The distillation is stopped when most of the spirit has distilled and the thermometer indicates 80°. A further purification may be effected by adding a little powdered permanganate of potash and by a second distillation, but this is rarely necessary. The same method of purification may be applied to over-proof spirit, which will henceforth be called spirit as distinguished from the purified product or absolute alcohol. 

If an especially pure product is desired, the acid may be reprecipitated by dissolving in an equal weight of warm water and adding three volumes of methyl alcohol. The loss in purification is 4-5 per cent. 

Methyl alcohol is the best solvent for purification. Desoxybenzoin tends to separate from ethyl alcohol as an oil. 

Washing with water, drying, and fractional distillation purifies vinylidene chloride. It forms an azeotrope with 6% by weight of methyl alcohol, and purification can be achieved by distillation of the azeotrope, followed by extraction of the methanol with water an inhibitor is usually added at this point. 

Thus, aniline, with a considerable excess of methyl alcohol and a catalytic amount of sulfuric acid, is heated in an autoclave at about 200°C for 5 or 6 hours at a high reaction pressure of 540 psi (3.7 MPa). Vacuum distillation is used for purification. 

Waste waters in the production of silicone monomers and polymers is an important economic issue. It is connected with environmental protection from air contamination and pollution of rivers, seas and other water bodies. Especially important in silicone production is the purification of acid waste waters from organic impurities (toluene, benzene, methyl alcohol, etc.). 

Purification of trinitroanisole. In the past trinitroanisole was purified by dissolving in methyl alcohol. The solution was filtered and the product precipitated by introducing the solution into water. Later the purification process was simplified, the crude trinitroanisole being agitated with hot water, the water decanted... 

Osmium tetraoxide (2 g.) and methyl alcohol (30 ml.) are treated with carbon monoxide (75 atmospheres) at 125° for 12 hours. On cooling, the yellow crystals of dodecacarbonyl-triosmium, Os3(CO)i2, are separated by filtration, washed with acetone, and dried in vacuo (20°, 10-1 mm. Hg). The sample thus obtained is usually sufficiently pure for most purposes. Further purification may be carried out either by sublimation at 130° in vacuo (10 2 mm. Hg) or by recrystallization from hot benzene. The yield of the decacarbonyl is usually in the range 70-80% (1.63 g.). 

A solution of trifluoroacetoamidine (37.8 mmol) in 20 ml methyl alcohol was treated with 4-methoxyphenylhydrazine hydrochloride (27 mmol) followed by 3.77 ml triethylamine, then stirred 6 hours at ambient temperature, and concentrated. The residue was treated with 20 ml water and 50 ml EtOAc/THF, 9 1, and the organic layer isolated. The aqueous layer was re-extracted with 50 ml EtOAc/THF, 9 1, and combined extracts were washed with water and brine. The solution was then dried using MgS04, concentrated, and 108.2% yield residue isolated and used without further purification. 

The Step 6 product (100 mmol) was dissolved in 400 ml THF and treated with the dropwise addition of bromine (100.0 mmol). The mixture was then treated with 10 ml methyl alcohol to maintain homogeneity and then stirred 30 minutes at ambient temperature. It was then concentrated and the solid residue triturated with 50 ml THF and three times with 50 ml EtOAc. The product was isolated as an yellow foam in quantitative yield after drying and used without further purification. 

A solution of 20.8 ml of 1.0 M Bis(trimethylsilyl)amide in THF lithium was added to an ice-cooled solution of the Step 1 product (18.9 mmol) dissolved in 20 ml THF followed by ethyl bromoacetate (94.5 mmol) and then stirred 30 minutes. The mixture was further treated with 10 ml ethylenediamine, then stirred an additional 30 minutes, and finally concentrated. The residue was dissolved in CH2C12, then washed with dilute HC1, dried with Na2S04, and reconcentrated. The residue was redissolved in 25 ml methyl alcohol and treated with 50 ml 1.0 M NaOH. Methyl alcohol was then removed and the basic solution extracted three times with 100 ml with CH2C12. The aqueous layer was acidified with 1.0M HC1 to pH 1 and further extracted with CH2C12. Organic extracts were dried with Na2S04, filtered, concentrated, and the product isolated in 98%. The product was used directly in the next step without additional purification. 

A solution of the Step 3 product (7.0 g) was treated with 10% palladium on carbon (800 mg) and 100 ml methyl alcohol, then hydrogenated 2 hours under 1 atm hydrogen, then filtered through diatomaceous earth. The solution was concentrated and the residue partitioned between CH2C12 and dilute HC1. The aqueous phase was further extracted twice with CH2C12 and these extracts were discarded. The aqueous layer was basified with 1 M NaOH, then re-extracted twice with CH2C12, dried with Na2S04, concentrated, and the residue isolated. The residue was used directly in the next step without additional purification. 

A solution of ethyl benzimidate hydrochloride (496.9 mmol) in 300.0 ml methyl alcohol was cooled to 0°C, then treated with a solution of aminoacetaldehyde dimethyl acetal (670.9 mmol) in 75 ml methyl alcohol at such a rate that the temperature was kept below 5°C. The solution was stirred 3 days at or below 5°C, then concentrated, and an yellow oil isolated. The residue was dissolved in 750 ml 1M NaOH, then extracted four times with 250 ml CH2C12, dried with MgS04, concentrated, and 108.13 g of crude /V-(2,2-dimethoxyethyl)benzamidine was isolated as an yellow oil. It was used without further purification. 

Acetic anhydride (10.96 mmol) was added to l-(4-fluorophcnyl-3(//)-(3(.S )-hydroxy-3-(4-fluorophenyl)propyl))-4(5)-(4-hydroxyphenyl)-2-azetidinone (4.98 mmol) containing dimethylaminopyridine (11.96 mmol) dissolved in 15 ml THF and the reaction monitored by TLC using 5% methyl alcohol/toluene. Thereafter, the mixture was then diluted with diethyl ether, washed with 1M HC1 and brine, and dried using Na2S04. The solution was concentrated and the product isolated in 100% yield and used without additional purification. 

The Step 4 product (14 mmol) was dissolved in 50 ml methyl alcohol and 10 ml HOAc, then treated with Pearlman s catalyst (20% Pd(OH)2, 1.04g, 20% (w/w)) and hydrogenated 18 hours under 50psi hydrogen. The reaction was filtered and the catalyst washed three times with 25ml methyl alcohol. The filtrate was concentrated and the product isolated as a white solid and used without further purification. 

The Step 1 product was stirred at 125°C in n-butyl acetate with /t-toluenesulfonic acid, then cooled, filtered, and washed with water. The mixture was then treated with water, ethyl alcohol, chlorotris(triphenylphosphine)rhodium, degassed, and heated for 3-5 hours at 75°C. The racemic acid was extracted with 2M NaOH, then washed with butyl acetate. It was then treated with methyl alcohol followed by the slow addition of 2 M HC1 and the product isolated by filtration. The material was used directly without further purification. 

The Step 4 product (0.8 mmol) dissolved in 2 ml THF was treated with 1ml 1M LiOH, then refluxed 1 hour, cooled, and treated with 1 ml 1M HC1. The mixture was concentrated and the residue (0.145 mmol) dissolved in 1ml DMF. The solution was treated with 3-(dimethoxyphosphoryloxy)-l,2,3-benzotriazine (0.18 mmol) followed by [3-(l-aminoethyl)-phenyl]-dimethylamine (0.145 mmol) dissolved in 0.5 ml DMF containing 81 jxl triethylamine. The solution was stirred 8 hours at 25°C, then filtered, and applied directly to a preparatory HPLC column (C18, 10-100% methyl alcohol/water/0.1% trifluoroacetic acid) for purification. The residue was then dissolved in 3 ml methyl alcohol and applied to a SAX column having hydroxide as the counter ion. The product was eluted with 10 ml methyl alcohol and isolated. 

Anhydrous, reagent-grade methyl alcohol was purchased from Mallinckrodt Inc. and used without purification. 

In an autoclave of 1-liter capacity, without stirrer, and heated by an oil bath, is placed 600 cc. dry methyl alcohol in which 23 grams of metallic sodium has previously been dissolved (reflux condenser), and to this is added 158 grams of pure o-nitrochlorobenzene (m.p. about 32°C. b.p. 243°). The autoclave is sealed and the heating is started. The temperature is raised to 120° over a period of 1 hour, held at this point for 3 hours, and finally held at 128° for 1 hour more. The pressure is 8 to 10 atmospheres. At the end of the reaction, the methyl alcohol is blown out through the valve into a good condenser. The recovered methyl alcohol can be used without purification in a subsequent run. The reaction product is removed from the autoclave, washing the latter out with hot water to remove the sodium chloride. The crude product is washed twice with five times its volume of hot water, separated, and distilled in vacuum. The yield is 136 grams, or 88 per cent of the theoretical amount. The product boils at 141° at 15 mm. 

The product from Step 4 (0.26 g), 5 ml DME, 0.16 ml NEt3, 0.92 ml methyl alcohol and ditriphenylphosphine palladium dichloride were mixed, placed under a carbon monox-ide/hydrogen balloon, and heated to 70 °C 24 hours. The reaction was then poured into 40 ml 1M HCl, the solid isolated, and dissolved in CH2Cl2/methyl alcohol. Eollowing the purification procedure of Step 3, the product was isolated in 59% yield, mp = 265-267 °C. H-NMR, IR, and MS data supplied. 

A catalytic amount of 5% palladium on carbon in dioxane was added to the product from Step 2 (11.0 mmol) dissolved in methyl alcohol/dioxane, 1 1, and hydrogenated at ambient temperature 4 hours. The mixture was filtered through celite, concentrated, and used in Step 4 without further purification. 

Preparative Methods conversion of (IR)-camphor into vicinal amino alcohol, followed by A -methylation using either aqueous formaldehyde and formic acid or methyl iodide. Purification bulb-to-bulb distillation, column chromatography. ... 

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