Methyl alcohol preparation

Guyot, J. Simon, L. J. Organic chemistry. - Action of sulphur trioxide and the oleum on methyl alcohol. Preparation of dimethyl sulphate Compt. Rend. (1919) 169 796... 

The 0 -S.V alcoholic potassium hydroxide solution Is prepared by dissolving 16g. of potassium hydroxide pellets in 500 ml. of alcohol (or industrial spirit) contained in a bottle closed by a cork. After standing for 24 hours, the clear solution is decanted or filtered from the residue of potassium carbonate. It is said that a solution in methyl alcohol has better keeping qualities than that in ethyl alcohol. 

Formaldehyde is a gas, b.p. — 21°, and is usually prepared by the dehydrogenation of methyl alcohol m the presence of heated copper or silver. By admitting air with the methyl alcohol vapour, part of the hydrogen is oxidised to give the heat necessary for the reaction ... 

Formaldehyde is a gas, b.p. — 21°, and cannot obviously be stored as such moreover, it polymerises readily in the liquid and the gaseous state. The commercial preparation, formalin, is an aqueous solution containing 35-40 per cent, of formaldehyde and some methyl alcohol. The preparation of a solution of formaldehyde may be demonstrated by the following experiment. 

Prepare a coil of copper wire by winding several turns around a glass tube. Heat the coil in the oxidising flame of a Bunsen burner for 1-2 minutes and plunge the spiral, whilst still red hot, into a test-tube containing a solution of 1 ml. of methyl alcohol and 5 ml. of water. Stopper the test-tube loosely, cool, remove the wire, and repeat the process two or three times. Observe the odour of the solution and use it (or formalin diluted with water) to carry out the following tests. 

The aluminium amalgam is prepared as described in Section 11,50,72. After washing with water, it slioidd lir.st be washed with methyl alcohol and Anally with a little dry benzene. 

P-Phenylethylamine is conveniently prepared by the hydrogenation under pressure of benzyl cyanide with Raney nickel catalyst (see Section VI,5) in the presence of either a saturated solution of dry ammonia in anhydrous methyl alcohol or of liquid ammonia the latter are added to suppress the formation of the secondary amine, di- P phenylethylamine ... 

Secondary and tertiary amines are not generally prepared in the laboratory. On the technical scale methylaniline is prepared by heating a mixture of aniline hydrochloride (55 parts) and methyl alcohol (16 parts) at 120° in an autoclave. For dimethylaniline, aniline and methyl alcohol are mixed in the proportion of 80 78, 8 parts of concentrated sulphuric acid are added and the mixture heated in an autoclave at 230-235° and a pressure of 25-30 atmospheres. Ethyl- and diethyl-anihne are prepared similarly. One method of isolating pure methyl- or ethyl-aniline from the commercial product consists in converting it into the Y-nitroso derivative with nitrous acid, followed by reduction of the nitroso compound with tin and hydrochloric acid ... 

Methyl p-toluenesulphonate. This, and other alkyl esters, may be prepared in a somewhat similar manner to the n-butyl ester with good results. Use 500 g. (632 ml.) of methyl alcohol contained in a 1 litre three-necked or bolt-head flask. Add 500 g. of powdered pure p-toluene-sulphonyl chloride with mechanical stirring. Add from a separatory funnel 420 g. of 25 per cent, sodium hydroxide solution drop by drop maintain the temperature of the mixture at 23-27°. When all the alkali has been introduced, test the mixture with litmus if it is not alkaline, add more alkali until the mixture is neutral. Allow to stand for several hours the lower layer is the eater and the upper one consists of alcohol. Separate the ester, wash it with water, then with 4 per cent, sodium carbonate solution and finally with water. Dry over a little anhydrous magnesium sulphate, and distil under reduced pressure. Collect the methyl p-toluenesulphonate at 161°/10 mm. this solidifies on cooling and melts at 28°. The yield is 440 g. 

Some neutral compounds (e.g., methyl alcohol) cannot be salted out with potassium carbonate distillation of the saturated aqueous potassium carbonate solution frequently yields the organic compound in a comparatively pure state, or at least in sufllciently concentrated a form to enable certain derivatives to be prepared. 

The alkah manganates(V) in strongly alkaline solution (45—50% at 0°C) are all blue. In water these manganate(V) compounds instantly disproportionate into manganate(VI) and Mn02. Lithium manganate(V), prepared by reaction of LiMnO and excess LiOH at 124°C, is an exception. This compound is relatively stable in 3% LiOH solution at 0°C and in absolute methyl alcohol. 

All of the methyl alcohol used in this preparation must be anhydrous and free of acetone. 

Dia2oaminoben2ene has also been prepared by the action of nitrous acid gas on aniline in alcohol by the action of silver nitrite on aniline hydrochloride and together with phenylurea by the action of nitrosophenylurea on aniline in methyl alcohol. Niementowski and Roszkowski have reported studies on the diazotization of aniline, aniline hydrochloride, and aniline sulfate with sodium nitrite and silver nitrite. The procedure described is adapted from that of Fischer. ... 

Technical formalin contains 8-10 per cent of methyl alcohol, so that it is not possible to use the table of densities (Note i of the preparation) for determining the formaldehyde content of the solutions. For example, a solution containing 37 per cent of formaldehyde and 10 per cent of methyl alcohol would have a density of 1.09 and correspond to 28 per cent of formaldehyde in pure water. In view of this, the recorded yield should probably be 64-66 per cent instead of 86-89 cent. 

Cellobiose was prepared first by Skraup and Konig by the saponification of the octaacetate with alcoholic potassium hydroxide, and the method was improved by Pringsheim and Merkatz.3 Aqueous barium hydroxide also has been employed for the purpose, and methyl alcoholic ammonia has been used extensively for the hydrolysis of carbohydrate acetates. The method of catalytic hydrolysis with a small quantity of sodium methylate was introduced by Zemplen,i who considered the action to be due to the addition of the reagent to the ester-carbonyl groups of the sugar acetate and the decomposition of the addition compound by reaction with alcohol. The present procedure, reported by Zemplen, Gerecs, and Hadacsy, is a considerable improvement over the original method (see Note 2). 

Harmine, C13H12ON2, crystallises from methyl alcohol in colourless rhombic prisms, m.p, 266°, [a]D 0°. The hydrochloride, m.p. 269-5-270-5° (Chen ), nitrate, platinichloride, m.p. 264-6°, acid chromate and oxalate crystallise well. The salts show a deep blue fluorescence in dilute solution. Harmine behaves as a monoacidic base. It gives a methiodide, from which methylharmine, needles, m.p. 209°, may be prepared, and this in turn yields methylharmine methiodide. On demethylation harmine yields the phenolic base harmol, C12H10ON2, m.p. 321°.i ... 

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