Patent GB-441884-A (GB)
Title: Manufacture of new water soluble monoazo dyestuffs
IPC: C09B29/06
Filed: 1934-07-27
Abstract: Monoazo dyestuffs especially useful for colouring acetate artificial silk are prepared by coupling a diazotized nitroamine of the benzene series devoid of sulphonic or carboxyl groups with an aryl-aminoalkanesulphonic acid of the formula Ar--NR--Alk--SO3H, where Ar stands for a residue of the benzene series devoid of sulphonic or carboxyl groups and having a free para position, R stands for hydrogen, alkyl, aralkyl or alkoxyalkyl, and Alk stands for ethylene or propylene, which may also carry a hydroxyl group. The dyestuffs are soluble in water, and may be applied to artificial silk from a neutral bath containing 1 per cent common salt or by printing.  The colours obtained vary from orange red to violet.  It is stated that the alkylene radical which carries the SO3H group is not split off as is the case with the formally related dyestuffs described in Specifications 197,809, 200,873, 212,029, [all in Class 2 (iii)], and 389,758, and accordingly deeper shades are obtained. In examples: (1) p-nitroaniline --> N-ethylphenyltaurine; (2) p - nitroaniline --> N - ethyl - N - b  - hydroxy-g -sulphopropylaniline; (3) p-nitroaniline --> phenyltaurine; (4) 2-chloro-4-nitroaniline --> phenyltaurine; (5) p-nitroaniline --> N-b -hydroxy - g  - sulphopropylaniline; (6) 2 : 6-dichloro - 4 - nitroaniline --> N - ethylphenyltaurine; (7) 2 : 6-dichloro-4-nitroaniline --> N - ethyl - N - b  - hydroxy - g  - sulphopropylaniline; (8) 2 : 4-dinitroaniline --> N-n-butyl-N - b  - hydroxy - g  - sulphopropylaniline; (9) 3-nitro-4-toluidine --> N-ethyl-N-b -hydroxy-g -sulphopropylanine; (10) 6-chloro-2 : 4-dinitroaniline --> N-ethyl-N-b -hydroxy-g -sulphopropylaniline; (11) 2-chloro-4-nitroaniline --> N - ethyl - N - b  - hydroxy - g  - sulphopropylaniline; (12) 3-nitroaniline --> N-ethylphenyltaurine; (13) 2-chloro-4-nitroaniline --> N-ethylphenyltaurine; (14) 2 : 4-dinitroaniline --> N-ethylphenyltaurine; (15) 4-nitroaniline --> N-ethyl-N - (b  - hydroxy - g  - sulphopropyl) - 3 - toluidine; (16) 2-chloro-4-nitroaniline --> N-ethyl-N-(b -hydroxy - g  - sulphopropyl) - 3 - toluidine; (17) 2 - chloro - 4 - nitroaniline --> N - b  - ethoxyethyl-N - phenyltaurine; (18) 2-chloro-4-nitroaniline --> N - b  - hydroxy - g  - sulphopropylaniline; (19) 2-chloro-4-nitroaniline --> N-ethyl-N-(b -sulphoethyl)-3-toluidine; (20) 2 : 6-dichloro-4-nitroaniline --> N-(b -hydroxy-g -sulphopropyl)-3-amino-4-methoxytoluene; (21) 6-chloro-2 : 4-dinitroaniline --> N-n-butyl-N-b -sulphopropyl-3-amino-4-methoxytoluene; (21) 2 : 4-dinitroaniline --> N-n-butyl-N-b -hydroxy-g -sulphopropyl-3-amino-4-methoxytoluene. The coupling components may be made by one or other of the following methods: (1) in the case where R in the general formula represents hydrogen, a primary amine of the benzene series is reacted in aqueous solution in the presence of an acid binding agent such as chalk with the appropriate halogen alkane sulphonic acid; (2) in the case where R in the general formula is alkyl, aralkyl or alkoxyalkyl, the corresponding compounds where R is hydrogen are prepared as in (1) above and then reacted with the appropriate halide; (3) in some cases the tertiary amine coupling components may be more conveniently prepared by reacting a secondary benzene amine with a suitable halogen-alkane-sulphonic acid.  An aqueous solution of the sodium salt of N - n - butyl - N - b -hydroxy-g -sulphopropyl-3-amino-4-methoxy toluene is prepared by refluxing the sodium salt of a -chloro-b -hydroxypropane - g  - sulphonic acid with 3 - amino - 4 - methoxytoluene in aqueous medium in the presence of chalk to give N-b -hydroxy-g -sulphopropyl-3-amino-4-methoxytoluene, and then refluxing this in aqueous medium in the presence of chalk with n-butyl bromide.  Sodium carbonate is then added to give the sodium salt.  An aqueous solution of N-n-butyl-N-b -hydroxy-g -sulphopropyl-3-toluidine is similarly prepared starting from 3-toluidine.  Samples furnished under Sect. 2 (5) are of (1) p-nitroaniline --> N-b -sulphoethyl-N-benzyl-3-toluidine; (2) 2 : 4 - dinitroaniline --> N - b  - hydroxy - g  - sulphopropyl - 3 - toluidine.  An aqueous solution of the sodium salt of N-b -hydroxy-g -sulphopropyl-N-benzyl-m-toluidine is prepared by refluxing the sodium salt of a  - chloro - b  - hydroxypropane - g  - sulphonic acid with m-toluidine in the presence of chalk to give N-b -hydroxy-g -sulphopropyl-m-toluidine, and then refluxing the sodium salt of this compound in the presence of chalk with benzyl chloride.  The sodium salt of N-b -sulphoethyl-N-benzyl-3-toluidine is similarly prepared starting from sodium -b -chloroethane sulphonate.