GB388874A - Improvements in the manufacture and production of nitriles - Google Patents

Abstract

Nitriles of hydroxyalkylamino carboxylic acids are manufactured by the action of hydrocyanic acid on oxazolidines of the formula <FORM:0388874/IV/1> where Z is hydrogen or an alkyl, hydroxyalkyl, aminoalkyl, cycloalkyl or aryl radicle and X is hydrogen or alkyl, obtained by the reaction of primary or secondary hydroxyalkylamines <FORM:0388874/IV/2> with aliphatic aldehydes or ketones. The reaction may be carried out by acting with gaseous or liquid hydrocyanic acid or an aqueous solution thereof on the said oxazolidines, or by employing an aqueous solution of a cyanide, e.g. an alkali or alkaline-earth metal cyanide, and introducing an acid stronger than hydrocyanic acid, e.g. carbon dioxide, hydrochloric or sulphonic acid into the mixture. Alternatively the aliphatic aldehyde or ketone is first reacted with the hydrocyanic acid and the cyanhydrin formed is reacted with the hydroxyalkylamine, or the latter is first mixed with the hydrocyanic acid and the aldehyde or ketone then added. As hydroxyalkylamines may be employed mono- or di-ethanolamine, mono- or di-b -hydroxypropylamine, N-ethyl-, N-propyl-, N-n-butyl-, N-hexyl-, N-cyclohexyl-, or N-phenyl-N-hydroxyethylamines and the corresponding N-b -hydroxypropyl-, butyl- and amyl-amines, also N-hydroxyalkyl polyamines, e.g. N-aminoethyl-N-hydroxyethylamine. The hydroxyalkylamines may be obtained by the action of an alkylene oxide on primary amines or ammonia in the presence of water, e.g. N-cyclohexyl-N-hydroxyethylamine may be prepared from cyclohexylamine and ethylene oxide, and the various hydroxypropylamines from propylene oxide and ethylamine, propylamine, butylamine, hexylamine, cyclohexylamine or aniline respectively. As aliphatic aldehydes and ketones may be employed formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde and homologues thereof, acetone and its homologues, e.g. methylpropyl ketone. The reactions may be carried out at 5-10 DEG C., or preferably at somewhat higher temperatures such as 20-40 DEG C., the reaction being accelerated or finished by warming to 50-60 DEG C. or up to 100 DEG C. The products may be converted by saponification into the corresponding carboxylic acids or by catalytic hydrogenation at increased pressure into amines. Those which contain a hydrogen atom attached to the nitrogen atom of the amino group may be reacted with esters of chlorocarboxylic acids, e.g. the cetyl ester of chlorocarbonic acid (obtainable by the action of phosgene on cetyl alcohol at 0 DEG C.) or with fatty acid chlorides, e.g. stearic chloride, to produce compounds having, for example in the case of the nitrile of hydroxyethylaminoacetic acid, the composition <FORM:0388874/IV/3> where R.CO is the radicle of the ester or of the fatty acid. In examples: (1) aqueous formaldehyde is added to monoethanolamine and to the oxazolidine formed is added sodium cyanide followed by the introduction of carbon dioxide, to produce the nitrile of hydroxyethylaminoacetic acid; (2) the same product is obtained by reacting formaldehyde cyanhydrin with monoethanolamine, or by adding aqueous hydrochloric acid to a sodium cyanide solution and then adding monoethanolamine followed by aqueous formaldehyde; (3) diethanolamine is reacted with aqueous formaldehyde yielding hydroxyethyloxazolidine, which is treated with anhydrous hydrocyanic acid to produce the nitrile of di-(hydroxyethyl)-aminoacetic acid; the diethanolamine may be replaced by monoethanolethylenediamine; (4) n-butyraldehyde is reacted with an aqueous solution of b -hydroxy-n-propylamine to produce b -methyl-m -n-propyl-oxazolidine, which with gaseous hydrocyanic acid yields the nitrile of a -(2-hydroxy-n-propyl)-amino-n-valeric acid; (5) an aqueous solution of n-butyraldehyde is reacted with N-ethanolaniline and the oxazolidine formed is treated with anhydrous liquid hydrocyanic acid, producing the nitrile of a -(N-phenyl-N-2-hydroxyethyl)-amino-n-valeric acid; the ethanolaniline may be replaced by cyclohexylethanolamine or n-butylethanolamine, and the n-butyraldehyde by acetaldehyde; (6) methylisopropyl ketone is reacted with an aqueous solution of b -hydroxy-n-propylamine and the resulting oxazolidine is treated with sodium cyanide and carbon dioxide to produce the nitrile <FORM:0388874/IV/4> the methylisopropylketone may be replaced by acetone; (7) N-ethanolaniline is reacted with aqueous formaldehyde and the oxazolidine obtained is treated with gaseous hydrocyanic acid to yield the nitrile of N-phenyl-N-b -hydroxyethylaminoacetic acid; the product may be saponified to the corresponding acid by means of caustic soda.