GB648886A - Improvements in or relating to the preparation of amides and/or amino acids - Google Patents

Abstract

N-substituted amides of b -hydroxycarboxylic acids and N-substituted amino-acids are prepared by reacting b -lactones with (a) aliphatic or cycloaliphatic unsubstituted primary or secondary amines or aliphatic or cycloaliphatic substituted primary or secondary amines in which no substituent is a neutralized acidic group, or (b) unsaturated cyclic primary amines containing only carbon, hydrogen, and nitrogen, or (c) hydrazines p or amidines. The amides may lose water to give the corresponding amides of a ,b -unsaturated carboxylic acids. The b -lactones may be obtained from reaction of ketenes with aldehydes or ketones as in Specification 649,028. The amines used include alkyl, alkenyl, and alkynyl monamines, alkylene diamines and polyamines, which are exemplified, aryl-substituted aliphatic primary amines, e.g. benzylamine, benzohydrylamine, phenyl ethylamine, and p-xylylene diamine, alicyclic primary amines such as cyclohexylamine, and cyclohexylene diamines, aromatic primary monoamines, and diamines or polyamines wherein at least one amine group is primary, heterocyclic amines, e.g. pyridyl, and quinolyl amines, secondary aliphatic and cyclic monoamines, including dicyclohexylamine, ethyleneimine, piperidine and pipecolines, and polyamines such as piperazine, other primary and secondary amines containing other nitrogen atoms in addition to hydrogen-bearing nitrogen, e.g. b -(diethylamino)-ethylamine, and b -cyanoethylamine, or containing oxygen in oxy and/or oxo groups, e.g. furfurylamine, morpholine, b - ethoxy - ethylamine, hydroxy - substituted amines, acetonylamine, amino-acids, and their esters and amides, and compounds where oxygen is in oxo groups linked to nitrogen other than amino nitrogen, e.g. b -nitro-ethylamine, or containing other elements such as sulphur, chlorine or bromine instead of or in addition to oxygen, e.g. chlorethylamine, 2,3-dichlorpropylamine, aminomethyl ethyl sulphide, b ,b 1-diamino ethyl sulphide, g -mercapto-propylamine, cysteine, cystine, and taurine. Hydrazines include phenyl, ethyl, and benzyl hydrazines, and amidines include acetamidine, guanidine, guanylhydrazine, and dicyandiamide. The invention is illustrated by reactions of b -propiolactone with methylamine, dimethylamine, diethanolamine, aniline, and phenylhydrazine. Other b -lactones used include b -isobutyrolactone, n - butyrolactone, valerolactone, isovalerolactone, n-caprolactone, a -ethyl, isopropyl or butyl b -propiolactone, b - methyl - b - valerolactone, b - cyclohexyl, phenyl or benzyl b -propiolactone, and other compounds having the b -lactone structure and groups containing elements such as oxygen, nitrogen, sulphur, and halogen attached to the a - and b -carbons, e.g. b ,b -dimethyl-b -propiolactone - a - carboxylic acid, b - (o - nitro - m - chlor-phenyl)-b -propiolactone, and a -bromob ,b -dimethyl-b -propiolactone-a -carboxylic acid. Solvents and diluents may be used, especially with solid reactants. Temperature is generally below 100, from - 10 DEG to 50 DEG C. being preferred. The products are used in preparing monomers for synthetic resin and rubber, and for production of artificial fibres, plasticizers, and pharmaceuticals. In examples: (1) b -propiolactone is added to aniline at 10-30 DEG C., giving N-phenyl hydracrylamide, which on distillation yields N-phenyl acrylamide, and b -N-phenyl-amino-propionic acid. The N-phenyl hydracrylamide is cyclized, e.g. with aluminium chloride, to give hydrocarbostyril; (2) b -propiolactone is added to aqueous aniline hydrochloride at 20 DEG C. and the product distilled; (3) p-toluidine similarly gives N-(p-toluyl)-hydracrylamide and acrylamide; (4) o- or p-phenylenediamine is converted to its hydracrylamide; (5) methylamine reacts similarly at - 10 DEG C. yielding N-methylhydracrylamide and acrylamide; (6) phenylhydrazine yields hydracrylphenylhydrazide; (7) and (8) dimethylamine and diethylamine give similar products as does ethyleneimine; (9) morpholine yields N-carboxyethyl morpholine; (10) and (11) diethanolamine and ethanolamine give NN-di-2-hydroxyethyl and N-2-hydroxyethyl-b -amino-propionic acid respectively; (12) glycine yields N-carboxymethyl hydracrylamide.