Patent GB-479848-A (GB)
Title: Manufacture of azo dyestuffs and intermediates
IPC: C09B29/32
Filed: 1936-08-10
Abstract: Mono - a  - furoacetylarylamines are manufactured by reacting an ester of a -furoacetic acid with a primary aromatic monoamine, preferably in the presence of an inert solvent and at an elevated temperature, and, if desired, in the presence of a catalyst such as is useful in the preparation of acetoacetylarylamines, e.g. pyridine, advantageously under reflux arranged so that the alcohol liberated is distilled off as it is formed.  As starting materials may be employed on the one hand the ethyl, methyl, propyl, butyl or higher esters of a -furoacetic acid, and on the other hand primary aromatic amines in general, particularly those of the benzene and naphthalene series, the nuclei of which may contain substituents such as halogens or alkyl, alkoxy, aryloxy, aralkyl, aralkoxy, aryl, hydroaryloxy or trifluoroalkyl groups.  In examples, a -furoacetic ethyl ester is refluxed with xylene and there is added a solution in xylene of: (1) p-chloraniline and pyridine; (2) p-toluidine and pyridine; (3) p-phenetidine and pyridine; (4) 2 : 5-diethoxyaniline; (5) 4-chloro-2-aminotoluene and pyridine; in example (6), a -furoacetic ethyl ester is added to a boiling solution of 2-methoxy-1-naphthylamine in xylene.  A table gives the properties of the a -furoacetyl derivatives of: (7) 4-chloro-2 : 5-dimethylaniline; (8) 4-chloro2 : 5-diethoxyaniline; (9) o-anisidine; (10) 2 : 5 - dimethoxyaniline; (11) 5 - chloro - 2-methoxyaniline; (12) p-anisidine.  Azo dyes, forming upon the material; cellulose derivatives and regenerated celluloses, dyeing; printing.--Water-insoluble azo dyestuffs are manufactured by coupling on the fibre, e.g. cotton, regenerated cellulose, cellulose esters or ethers, wool or silk, a mono-a -furoacetylarylamine with a diazotized primary arylamine, e.g. of the benzene, naphthalene, diphenyl, anthracene, fluorene, carbazole, azobenzene, stilbene, azoxybenzene, diphenylamine, diphenyl ether, diphenylsulphone, phenanthrene or pyrene series and preferably containing one or more non - solubilizing nuclear substituents, e.g. halogens or alkyl, alkoxy, aryl, aryloxy, aralkyl, aralkoxy, nitro, acylamino, trifluoromethyl, carboxylamido or sulphonamido groups.  The diazo component is preferably diazotized and coupled with a stabilizing agent, e.g. piperidine-a -carboxylic acid, sarcosine, ethyltaurine, proline, 4-sulpho-2-aminobenzoic acid or methylglucamine, and the diazoamino compound is mixed with the coupling component in an alkaline medium. Alternatively, the diazo components may be employed in the form of diazo salts or nitrosamines.  For printing, the stabilized diazo compound and coupling component are applied in admixture in a basic paste, and the print is developed by exposure to the fumes of an acid, e.g. acetic acid, usually in the presence of water vapour.  In examples: (13) cotton is printed with a paste containing the diazoimino compound from diazotized 4-chloro-2-aminotoluene and the sodium salt of piperidine-a -carboxylic acid, 4 - ethoxy - a  - furoacetanilide, the substance known under the Registered Trade Mark "Cellosolve," caustic soda solution and starch gum tragacanth thickener, and a reddish yellow print is developed by exposure to the vapours from a boiling acetic acid solution; (14) 4-chloro-2-aminoanisole is employed as diazo component in the process of (13); (15) 6-chloro-2-aminotoluene is similarly employed; (16) 4-chloro-2 : 5-dimethyl-a -furoacetanilide is used as coupling component in the process of (15); (17) 5-chloro-2-methyl-a -furoacetanilide is similarly employed.  The following additional components are specified: diazo components: 2-methoxy-1-naphthylamine, 2-, 3- and 4-methoxyaniline, 2-, 3- and 4-phenoxyaniline, 2-, 3- and 4-ethoxyaniline, 2- chloro-5-methylaniline, 2-, 3- and 4-methylaniline, 2-methoxy-5-methylaniline, 2-methoxy-4-chloro-5-methylaniline, 2 : 5-dimethoxyaniline, 2 : 5-diethoxyaniline, 2 : 5 - dimethoxy - 4 - chloraniline, 5-bromo - 2 - methoxyaniline, 3 - iodo - 6 - methoxyaniline, 3-methyl-4-chloraniline, 3-bromo- and -chloro-6-ethoxyaniline, 3-bromo-6-phenoxyaniline, 3-bromo-6-methylaniline, 3-bromo-5-methylaniline, 3 - chloro - 6 - phenoxyaniline, 2 : 5-dimethyl-4-chloroaniline, 4-ethylaniline, 4 - chloro- and -bromo - 2 - methoxyaniline, 4-bromo-and-chloro-2-ethoxyaniline, 4-bromo-2-phenoxyaniline, 2-chloro-4-methoxyaniline, 4 - chloro - 2 - methylaniline, 3 - bromo- and -chloro-4-methylaniline, 4-bromo-3-methylaniline, 4 - chloro - 2 : 5 - dimethylaniline, 4-chloro-2-phenoxyaniline, 3-chloro-4-methoxyaniline, 2-chloro-4-phenoxyaniline, 4-chloro-2 : 5 - diethoxyaniline, 3 - chloro - 2 - methoxyaniline, a - and b -naphthylamine; coupling components: the a -furoacetyl derivatives of 4-methylaniline, 2 : 5-diethoxyaniline, 4-chloro-2 : 5-diethoxyaniline, 4-chloraniline, 5-chloro-2-methylaniline, 2 - methoxy - 1 - naphthylamine, 2- and 4-methoxyaniline, 2 : 5-dimethoxyaniline and 5-chloro-2-methoxyaniline.