Patent GB-584956-A (GB)
Title: New monoazo dyestuffs
IPC: C09B29/08
Filed: 1944-08-28
Abstract: Monoazo dyestuffs are manufactured by coupling a diazotized p-nitraniline, which may carry substituents other than sulphonic acid, carboxylic acid or cyano groups, with the sulphuric ester of an N-hydroxylalkyl-N-phenoxy- or naphthoxy-alkylaniline (the last-mentioned alkyl residue containing 2, 3, 4 or 5 carbon atoms), which may carry further substituents other than sulphonic acid or carboxyl substituents subject to its being capable of coupling in the para-position to the nitrogen atom, or with a salt thereof. Alternatively, the free N-hydroxyalkyl 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 artificial silk in dischargeable orange, red, crimson, violet, blue and brown shades from a neutral, slightly acid or slightly alkaline bath, e.g. from a neutral bath containing Glauber's salt or sodium chloride, and are suitable for application from dilute or "long" liquors such as are employed in dyeing with the winch. They may also be used for printing cellulose acetate artificial silk and for dyeing wool, natural silk, tin weighted silk, leather and nylon.  Examples describe the production of the following dyestuffs: p-nitraniline --> the sodium salt of the sulphuric ester of N-b -hydroxyethyl-N-b 1-phenoxyethylaniline, N-b -hydroxyethyl - N - g 1 - phenoxypropylaniline, N - b  - hydroxyethyl - N - b 1 - phenoxyethyl - m - chloraniline, N - b -hydroxyethyl - N - b 1-p-tolyloxyethylaniline, N - b  - hydroxyethyl - N - b 1 - p - chlorophenoxyethylaniline, N - b  - hydroxy - n - propyl - N - b 1 - phenoxyethylaniline, N - b  - hydroxyethyl - N - b 1 - phenoxyethyl - m - amino - anisole, N - b  - hydroxyethyl - N - b 1 - phenoxy - ethyl - m - aminotoluene or N - b  - hydroxyethyl-N - b 1 - (a 11-naphthoxy)-ethylaniline; o-chloro-p-nitraniline --> the sodium salt of the sulphuric ester of N-b -hydroxyethyl-N-b 1-phenoxyethylaniline, N - b  - hydroxyethyl - N - g 1 - phenoxypropylaniline, N-b -hydroxyethyl-N-b 1-phenoxyethyl-m-aminotoluene or N-b -hydroxyethyl - N - b 1 - phenoxyethyl - m - chloroaniline; 2 : 6 - dichloro - 4 - nitraniline --> the sodium salt of the sulphuric ester of N-b -hydroxyethyl-N - b 1 - p - chlorophenoxyethylaniline, N - b  - hydroxyethyl - N - b 1 - phenoxyethyl - m - amino - toluene or N - b -hydroxyethyl-N-b 1-p-tolyloxyethylaniline; 2 : 4-dinitroaniline or its 6-chloro-derivative --> the sodium salt of the sulphuric ester of N-b -hydroxyethyl-N-b 1-phenoxyethyl-m-aminotoluene; o-bromo-p-nitraniline --> N - b  - hydroxyethyl - N - b 1 - phenoxyethyl - m - chloroaniline sulphuric ester; 6-bromo-2 : 4-dinitroaniline --> N - b  - hydroxyethyl - N - b 1 - phenoxyethylcresidine sulphuric ester.  In a further example, p-nitraniline is diazotized and coupled with N-b -hydroxyethyl-N-b 1-phenoxyethylaniline, and the product is treated with 70-80 per cent sulphuric acid.  Other components specified are: diazo components: 2-chloro-6-bromo-4-nitraniline, 2 : 6-dibromo-4-nitraniline, 5-nitro-2-aminoanisole and 5-nitro-2-aminotoluene; coupling components: N-b -hydroxyethyl - N - b 1 - phenoxyethyl - m - acetylaminoaniline, N-o -hydroxy - n - amyl - N - b 1 - phenoxyethylaniline and N - b  - hydroxyethyl - N-o 1-phenoxy-n-amylaniline.  Specifications 181,750 and 237,739, [both in Class 2 (iii)], are referred to.  N - Hydroxyalkyl-N - phenoxy- and naphthoxy - alkylanilines described above are obtainable (except as described below) by reacting the appropriate hydroxyalkylated arylamine with the appropriate aryloxyalkyl chloride or bromide in boiling aqueous medium in the presence of an acid-binding agent, e.g. chalk.  o -Phenoxy-n-amyl bromide (required for the preparation of N - b  - hydroxyethyl - N -o 1-phenoxy-n-amylaniline) is obtainable by reacting sodium phenate with o -chloroamyl acetate, hydrolysing the acetoxy group by boiling with aqueous hydrochloric acid and treating the product with hydrobromic acid.  N - b -Hydroxyethyl-N - b 1-phenoxyethylaniline is obtainable by reacting aniline with b -phenoxyethyl bromide and the resulting N-b -phenoxyethylaniline with ethylene chlorhydrin in boiling aqueous suspension in the presence of chalk.  N - b  - Hydroxy-n-propyl-N-b 1-phenoxyethylaniline is obtainable by heating N-b -phenoxyethylaniline with propylene oxide under pressure.  N-o -Hydroxy - n - amyl - N - b 1 - phenoxyethylaniline is obtainable by reacting o -chloro-n-amyl acetate with excess of aniline, reacting the resulting N-o -acetoxy-n-amylaniline with b -phenoxyethyl bromide and hydrolysing the acetoxy group by boiling the product with aqueous hydrochloric acid.  Sulphuric esters are obtainable by treating the foregoing hydroxylalkyl compounds with chlorosulphonic acid in ethylene dichloride or tetrachlorethane.