Alcohols hydrogen

The above example serves to iUustrate the basis of the procedure employed for the characterisation of aUphatic esters, viz., hydrolysis to, and identification of, the parent acids and alcohols. Most esters are liquids a notable exception is dimethyl oxalate, m.p. 54°. Many have pleasant, often fruit-hke, odours. Many dry esters react with sodium, but less readily than do alcohols hydrogen is evolved particularly on warming, and a sohd sodio derivative may separate on coohng (e.j/., ethyl acetate yields ethyl sodioacetoacetate ethyl adipate gives ethyl sodio cj/cZopentanone carboxylate). 

Thiazole acid chlorides react with diazomethane to give the diazoketone. The later reacts with alcoholic hydrogen chloride to give chloroacetylthiazole (Scheme 16). However, the Wolff rearrangement of the diazoketone is not consistently satisfactory (82). Heated with alcohol in the presence of copper oxide the 5-diazomethylketone (24) gives ethyl 5-thiazoleacetate (25) instead of the expected ethoxymethyl 5-thiazolyl ketone (Scheme 17) (83). 

Halogens add to butenediol, giving 2,3-dihalo-l,4-butanediol (90,91). In a reaction typical of aHyhc alcohols, hydrogen haUdes cause substitution of halogen for hydroxyl (103). 

Decomposition products from primary and secondary dialkyl peroxides include aldehydes, ketones, alcohols, hydrogen, hydrocarbons, carbon monoxide, and carbon dioxide (44). 

Phenazine reacts with benzenesulphinic acid in alcoholic hydrogen chloride to give 2-phenazinyl phenyl sulfone (26 Scheme 4), presumably by an intermediate 5,10-dihy-drophenazine this reaction is evidently a useful method of preparing 2-substituted phenazines, since the sulfone is readily displaced in substitution reactions. 

The treatment of 3-acylisoxazoles (438) with hydroxylamine hydrochloride gives furazan ketones (439). On the other hand, furazan ketones (439) rearrange to 3-acylisoxazoles (438) with a loss of hydroxylamine under the influence of a mineral acid. Thus, by refluxing phenacylphenylfurazan with concentrated alcoholic hydrogen chloride, 3-benzoyl-5-phenyl-isoxazole is formed similarly, phenyl(phenacylphenyl)furazan gives 3-benzoyl-3,5-diphenyl-isoxazole (62HC(17)1, p. 35). 

Apart from the syntheses already quoted as of possible biological interest, mention must be made of a series which are primarily of chemical interest. Kermack, Perkin and Rob mson prepared norharman, i.e., /S-carboline (VII) by warming A-methylindole-2-carboxyacetalylamide (XVIII) with alcoholic hydrogen chloride, thereby converting it into 2-keto-l-methyl-2 3-dihydro-/S-carboline (XIX), which on distillation... 

In the sjmthesis of evodiamine effected by Asahina and Ohta,i N-methylanthranilic acid was converted by ethyl chloroformate into N-methylisatoic anhydride, which, on treatment with 3- -aminoethylindole, furnished 3-/3-o-methylaminobenzoylaminoethylindole (III), and this with ethyl orthoformate at 175-180° gave dZ-evodiamine, m.p. 278°, convertible by boiling alcoholic hydrogen chloride into Zsoevodiamine, m.p. 147°, as shown above. 

The use of acetone cyanohydrin (in an exchange reaction) instead of alcoholic hydrogen cyanide affords even higher yields of 17-cyanohydrins and the former reagent has the added advantage of reacting quantitatively and essentially selectively with the 17-ketone of androst-4-ene-3,17-dione. Sodium hydroxide promotes the exchange reaction in some cases. 

The first indolization of an arylhydrazone was reported in 1983 by Fischer and Jourdan" by treatment of pyruvic acid 1-methylphenylhydrazone 3 with alcoholic hydrogen chloride. However, it was not until the following year that Fischer and Hess identified the product from this reaction as 1-methyl indole-2-carboxylic acid 4. 

Paraformaldehyde (7.5 g) (0.25 mol) and 18.3 g (0.25 mol) of diethylamine are mixed in 25 cc of alcohol and warmed until a clear solution Is obtained. The solution is cooled and mixed with 26.6 g (0.10 mol) of 3,3 -diallyl-4,4 -biphenol in 25 cc of alcohol. After standing several hours, the solution is warmed for one hour on the steam bath, allowing the alcohol to boil off. The residue is then taken up in ether and water, the ether layer separated and washed with 2% sodium hydroxide solution and finally with water. The washed ether solution is dried over solid potassium carbonate, and filtered. After acidifying with alcoholic hydrogen chloride, the ether is distilled off and the alcoholic residue diluted with an equal volume of acetone. The crystalline hydrochloride is filtered off, triturated with alcohol, diluted with several volumes of acetone, filtered and dried MP 209°-210°C. 

The following technique is described in U.S. Patent 2,541,104. A solution of 2.0 g of 3(a )-hydroxy-21-acetoxy-11,20-diketo-pregnane, which can be prepared as described in Helv. Chim. Acta 27, 1287 (1944), is treated in a mixture of 25 cc of alcohol and 6.4 cc of acetic acid at 0°C with 6.0 g of potassium cyanide. The solution is allowed to warm to room temperature and after 3 hours is diluted with water. The addition of a large volume of water to the alcohol-hydrogen cyanide mixture precipitates a gum which is extracted with chloroform or ethyl acetate. The extract is washed with water, and evaporated to small volume under reduced pressure. The crystalline precipitate (1.3 g) consists of 3(a ),20-dihvdroxy-20-cvano-21-acetoxy-11-keto-pregnane dec. 175° to 185°C. 

A solution of 1.0 gram of 10-[3 -(N-acetoxyethylpiperazinyl)-propyl]-2-trifluoromethyl-phenothiazine in 25 ml of 1 N hydrochloric acid is heated at reflux briefly. Neutralization with dilute sodium carbonate solution and extraction with benzene gives the oily base, 10-[3 -(N-(3-hydroxyethylpiperazinyl)-propyl]-2-trifluoromethylphenothiazine. The base is reacted with an excess of an alcoholic hydrogen chloride solution. Trituration with ether separates crystals of the dihydrochloride salt, MP 224° to 226°C, (from U.S. Patent 3,058,979). 

Filtrate A was extracted with ether, dried, acidified with alcoholic hydrogen chloride, and the salt which separated was collected end dried. There was thus obtained, when all the salt had been combined, 250 grams (69.3% of the theoretical yield) of 2-( 1,2,3,4-tetra-hydro-1-naphthyl)imidazoline hydrochloride, melting at 256° to 257°C. 

As discussed in Section 7.4.2.5, the reduction of tetrazolium salts to formazans often results in further reduction products. As seen in Scheme 24, reduction of formazans with ammonium sulfide leads to the hydrazidine 161. The reduction can proceed further eliminating an arylamine, yielding an amidrazone, e.g., 162.364 By contrast, alcoholic hydrogen sulfide attacks... 

Alcohols, Hydrogen chloride See Hydrogen chloride Alcohols, etc. 

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