Patent GB-588409-A (GB)
Title: New monoazo dyestuffs
IPC: C09B29/08
Filed: 1945-02-16
Abstract: Monoazo dyestuffs are manufactured by coupling a diazotized p-nitraniline, which may carry substituents other than sulphonic acid or carboxylic acid groups, with a sulphuric ester (or salt thereof) of a tertiary arylamino-compound capable of coupling and of the general formula C6H5NR-CH2-CH(OH)-CH2OR1 wherein the C6H5 radical may contain substituents other than sulphonic acid or carboxylic acid groups in the 2-, 3-, 5- and 6-positions, R represents an alkyl radical, and R1 an aromatic radical of the benzene series, which may contain halogen, alkyl or alkoxy substituents, or of the naphthalene series. Alternatively, the free hydroxy compound is used as coupling component and the dyestuff is converted into its sulphuric ester by treatment with sulphuric acid or other known reagent for this purpose.  The products, in the form of their alkali metal or ammonium salts, dye cellulose acetate rayon in dischargeable red, violet, blue or brown shades from a neutral, slightly acid or slightly alkaline bath, e.g. one containing Glauber's salt or sodium chloride, and are suitable for dyeing from the winch with dilute dyebaths.  They may also be used for printing cellulose acetate rayon and for dyeing nylon, wool, natural silk, tin-weighted silk and leather.  Examples described the production of the following dyestuffs: p-nitraniline, 2-chloro-4-nitraniline, 2 : 6-dichloro-4-nitraniline or 2 : 4 - dinitraniline --> the sodium salt of N - ethyl - N - b  - hydroxy-g -phenoxypropylaniline sulphuric ester; p-nitraniline --> the sulphuric ester of N - ethyl - N - b  - hydroxy-g -(p - methyl - phenoxy or a -naphthoxy)-propylaniline or of N - ethyl - N - b  - hydroxy-g -phenoxypropyl - m - toluidine or -m-chloroaniline; 2 : 4-dinitraniline --> N-methyl-N-b -hydroxy-g -phenoxypropylaniline sulphuric ester; 2-chloro-4-nitraniline --> N - ethyl - N - b -hydroxy-g -phenoxypropyl-m-anisidine sulphuric ester; 6-chloro-2 : 4-dinitraniline --> 1-N-n-butyl-N-b -hydroxy-g -phenoxypropylamino-2-methoxy-5-methyl -benzene sulphuric ester.  In a further example, p-nitraniline is diazotized and coupled with N - ethyl - N - b  - hydroxyl-g -(p-chlorophenoxy)-propylaniline and the product is treated with 85 per cent sulphuric acid.  Additional diazo components specified are: 2-bromo-, 2 : 5-dichloro-, 2 : 6-dibromo-, 2-bromo-6-chloro- and 2-cyano-4-nitraniline, 6-bromo-2 : 4-dinitraniline, 5 - nitro - 2 - aminoanisole and 5 - nitro - 2 - aminotoluene.  Specifications 181,750, 237,739, [both in Class 2 (iii)], 434,126 and 447,561 are referred to.  Tertiary arylamines of the formula given above are obtainable by treating the corresponding secondary amines C6H5NHR (e.g. ethylaniline), in boiling aqueous medium in the presence of an acid-binding agent such as chalk, with the corresponding chloro compounds ClCH2CHOHCH2OR1 (e.g. g -chloro-b -hydroxy-a -phenoxypropane), themselves obtainable by treating the appropriate phenol or naphthol with epichlorhydrin in the presence of an alkaline catalyst such as sodium hydroxide.  Sulphuric esters are obtainable by treating the foregoing tertiary arylamines with chlorosulphonic acid in an inert, solvent, e.g. ethylene dichloride or tetrachloroethane.