Patent GB-497572-A (GB)
Title: Process for the production of n-acylurethanes
Filed: 1937-10-29
Abstract: N-acyl urethanes of the general formula <FORM:0497572/IV/1> are prepared by treating urethanes of the formula <FORM:0497572/IV/2> with halogen substituted fatty acids, their halides, esters or anhydrides containing exchangeable halogen.  R2 in the above formul represents a substituted or unsubstituted alkyl, aralkyl, cycloalkyl or aryl residue, and R1 represents a substituted or unsubstituted aliphatic or hydroaromatic radical. The term acyl includes the residue of a saturated or unsaturated carboxylic acid which contains an exchangeable halogen atom.  At least one of the groups R1, R2 or acyl must be an aliphatic or alicyclic residue containing more than eight carbon atoms.  The acylation is preferably carried out by treating the urethanes in the presence of heat with halogen fatty acid halides with or without a solvent such as benzene or toluene. Acid binding agents such as pyridine or diethylaniline may also be present.  Urethanes suitable as parent materials for the process of the present invention include undecyl carbamic acid methyl, ethyl, propyl, butyl or amyl ester, heptadecyl carbamic acid ethyl or amyl ester, urethanes respectively made from the carboxylic acids of the naturally occurring or hydrogenated fats or oils such as the fatty acids from palmnut oil, coconut oil, soya bean oil, hydrogenated cod liver oil, or resins.  Also naphthenic acid, the carboxylic acids of camphor and fenchone, methyl carbamic acid, methyl, butyl, decyl, undecyl, dodecyl, octodecyl and oleic acid esters.  As acylating agents there may be used the halides, esters and anhydrides of organic carboxylic acids containing exchangeable halogen atoms. Acids mentioned include the a -halogen fatty acids, such as mono- and di-chloracetic acids, bromosuccinic acid, and a -bromolauric acid. Other halogen substituted acids are also suitable such as the chlorides of the benzylchloride-4-carboxylic acid, of the 2-chlorobenzoic acid and its substitution products such as the 2-chloro-1-benzoic-5-sulphonic acid.  The exchangeable halogen atom may be replaced by monovalent atom groupings such as -OR, -SR, -NR2, where R may be an organic or inorganic substituent.  -OR may be hydroxy, O-SO2H, or the residues of aliphatic, hydroaromatic, aliphatic-aromatic, or aromatic hydroxy compounds, such as of methyl, ethyl, benzyl alcohol, cyclohexanol, phenols, phenol sulphonic acids. Examples of this subgroup of acyl urethanes include the reaction products of N - chloroaceto - N - undecyl carbamic acid methyl ester and sodium phenolate, of N-chloroaceto-N-heptadecyl carbamic acid ethyl ester and the monosodium salt of glycerol.  The group -SR may be -SH, -S2O3H, -SO3H, or radicals of mercaptans.  These compounds may be prepared by the reaction of the halogen acyl urethanes with alkali mono and polysulphides, thiosulphates, sulphites or the alkali compounds of the mercaptans.  Suitable mercaptans mentioned include ethyl, dodecyl, phenyl and benzyl mercaptans, mercapto acetic acid, and a -mercaptobenzthiazole.  Examples of this sub-group include the reaction product of N-chlor-aceto-N-lauryl carbamic acid methyl ester with sodium thiophenolate, sodium sulphydrate, thiosulphates or sulphites.  The group -NR2 may be the primary or secondary amino group.  Suitable nitrogen compounds for reaction with the reactive halogen are ammonia, mono and dimethyl-, or ethyl-amine, mono-diethanolamine, amino acetic acid, aminoethane sulphonic acid, primary and secondary aromatic amines such as aniline and its substitution products, piperidine. Examples of this sub-group include the reaction products of N-chloraceto-N-heptadecyl carbamic acid alkyl esters with dimethylamine, methylaniline or taurin.  Water soluble compounds containing quadrivalent nitrogen atoms are obtained by the addition of tertiary amines such as trimethylamine, pyridine, dimethylaniline, tri-ethylamine, or by complete alkylation, or aralkylation, of the acylurethane derivatives made with ammonia or primary or secondary amines or with esters of low molecular alcohols such as dimethyl sulphate.  Water solubility may also be induced by the use of compounds introducing the -SO3H group, such as sulphite, formaldehyde-sulphite, thiosulphate, and aliphatic or aromatic sulphonic acids bearing hydroxy or amino groups such as hydroxy or amino ethanesulphonic acid, phenolsulphonic acid, and sulphanilic acid.  The water solubility may also be produced by after-sulphonation.  In examples: (1) chloracetic acid chloride is dropped into a toluene solution of undecylcarbamic acid methyl ester to give N-chloroaceto-N-undecyl carbamic acid methyl ester, which is further reacted with alkali phenolate to give N-phenoxy-aceto-N-undecyl-carbamic acid methyl ester.  To impart water solubility, the product may in addition be sulphonated. Instead of the above compounds there may be similarly employed heptadecylcarbamic acid ethyl ester, undecylcarbamic acid butyl ester, a -chloro butyric acid chloride, and a -chloropropionic acid chloride.  (2) N-chloroaceto-N-heptadecyl carbamic acid methyl ester made as in example (1) is treated with an aqueous solution of sodium sulphite to yield a water soluble product.  (3) N-chloroaceto-N-heptadecyl carbamic acid methyl ester is treated with sodium thiosulphate in alcohol to yield a water soluble product.  (4) The N-chloroacetylate made from hydrogenated fish oils by way of the carbamic acid methyl ester is added to an alkaline alcoholic solution of mercapto-benzene to give the corresponding N-phenylthioaceto derivative.  (5) N-chloroaceto-N-heptadecyl carbamic acid methyl ester is added to aqueous dimethylamine, and the product treated with dimethyl sulphate to give N-dimethylaminoaceto-N-heptadecyl carbamic acid methyl ester, which is a water soluble product useful for softening regenerated cellulose.  (6) N-chloroaceto-N-heptadecyl carbamic acid methyl ester is added to an alcoholic solution of trimethylamine to give a wax-like product which is easily soluble in water.  Other tertiary amines may be used in place of trimethylamine such as pyridine, nicotine, or tri-ethanolamine. (7) Chloroacetyl chloride is added to the urethane obtained from methylamine and the chloroformic ester of dodecyl alcohol to give N-chloroaceto-N-methyl carbamic acid dodecyl ester which is then treated with aqueous sodium sulphate to give a water soluble product.  Specification 497,506 is referred to.