Patent GB-779879-A (GB)
Title: Manufacture of new metalliferous mono-azo-dyestuffs
IPC: C09B45/14
Filed: 1954-03-01
Abstract: The invention comprises cobalt or chromium complexes containing less than one atom of metal per molecule of dyestuff of o:o1 - dioxy - monazo - dyestuffs free of sulphonic and carboxylic acid groups and of formula R1 - N=N - R2 where R1 is a naphthalene residue bound in the 1 - position to the azo linkage and substituted in the 2 - position by a hydroxyl group and in the 4 - position by a sulphonamide group, and R2 is the residue of a naphthol coupling component containing an OH group in vicinal position to the azo linkage or the residue of a coupling component bound to the azo linkage or the residue of a coupling component bound to the azo linkage in a position vicinal to an enoliable or enolised keto group. The metal dyestuffs are made by treating the unmetallized dyestuff or an - o - acyl derivative thereof with a chromium- or cobalt-yielding agent under the usual conditions for metallization.  Mixtures of the above unmetallized dyestuffs may be chromed or cobalted and mixtures of chromium- and cobalt-yielding agents may be used for metallization.  The unmetallized dyestuffs are advantageously made by converting an appropriate o:o1 - dioxy - monoazo - dyestuff containing a 4 - sulphonic acid group into its - o - acyl derivative, then the acid group to a sulphonyl halide group by treatment with a pentavalent phosphorus compound containing at least 3 halogen atoms in an inert solvent or dispersing medium, and finally converting the acid halide group to a sulphonamide group and hydrolysing the - o - acyl group if desired.  The o:o1 - dihydroxy-azo-dyestuffs containing sulphonic acid groups are prepared in conventional fashion, specified diazo components being 6 - nitro-, - chloro- and - methoxy - 1 - amino - 2 - naphthol - 4 sulphonic acid, and coupling components indicated are acetoacetyl-aminobenzenes or pyrazolones, e.g. 1 - phenyl - 3 - methyl - 5 - pyrazolone which may contain methyl, methoxy, chlorine or sulphonic acid groups in the phenyl nucleus. Other specified coupling components are 1 - and 2 - naphthol, 4 - methyl - and 5, 8 - dichloro - 1 - naphthol, 1 - naphthol - 3, - 4 -, - 5 - and - 8 - sulphonic acids and 2 - naphthol - 4, - 5 -, - 6 -, and - 7 - sulphonic acids, Conversion to the acyl derivatives may be effected with the free sulphonic acids or with alkali salts thereof. Specified acylating agents are acetyl, proponyl and butyryl chlorides and acetic anhydride, benzoyl chloride being preferred for naphthalene - azo - naphthalene dyestuffs.  Benzene, nitrobenzene, trichlorbenzene, dioxane and pyridine are typical of specified solvents or dispersion media for use in acylation which is preferably affected at 70-100 DEG C. Treatment with a phosphorus halide may be effected without separation of the acyl derivatives.  Specified phosphorus halides are the oxychloride oxybromide, pentabromide and pentachloride the latter being preferred.  The acid halide is separated at the end of the reaction in conventional fashion and treated with a compound containing at least one - N H- group, compounds of this type specified being ammonium, mono-methyl - and - ethyl - amines, dimethylamine, piperidine and morpholine. Condensation with the compound containing an - NH - group is effected in conventional fashion the - o - acyl group being simultaneously hydrolysed when a strongly basic amine is used.  Hydrolysers of the - o - acyl group may also occur during the separation of the sulphonyl halide.  The metalliferous dyestuffs are used for dyeing silk, leather, wool and fibres of superpoly - amide and - urethanes from weakly acid baths. Examples are provided of the use of certain of the above reagents in the preparation of metal dyestuffs which dye wool in brown, blue, red and grey tints.  Components containing an - NH - group used in the examples additional to those specified above are aniline, isopropylamine and 4 - and 2 - methoxy - 1 aminobenzene an additional acylating agent being p - chlorobenzoyl chloride. Specifications 637,404 and 779,880 are referred to.