Patent GB-350928-A (GB)
Title: Improvements in the manufacture of dyes and in the dyeing of cellulose esters or ethers
IPC: C09B1/20
Filed: 1930-02-17
Abstract: Cellulose esters or ethers, dyeing; aminoanthraquinone derivatives.-Cellulose esters or ethers are dyed with aminoanthraquinone derivatives containing as nuclear substituents the group <FORM:0350928/IV/1> (in which R and R1 are H, alkyl, or aryl) and one further auxochrome group, and the invention includes the manufacture of such derivatives by either (a) converting an aminoanthraquinonecarboxylic acid or acid halide into its amide, alkylamide, or arylamide by known methods or saponifying a corresponding nitrile to its amide, and, in case the initial material does not contain a further auxochrome group as substituent of the said anthraquinone nucleus, introducing such a group, or (b) a modification of such a process in which the starting material is a nitroanthraquinonecarboxylic acid or acid halide and the nitro group is subsequently reduced to an amino group, or (c) a further modification in which the starting material is an anthraquinonecarboxylic acid or acid halide and an amino group is subsequently introduced in addition to the further auxochrome group. The derivatives in which the amide group is in o-position to an a -amino group are specially suitable.  The dyestuffs may be applied in solution or suspension, e.g. emulsified with turkey red oils.  The following examples are specified.  (1) 1-Aminoanthraquinone-2-carboxylic acid chloride (obtainable by action of thionyl chloride on 1-aminoanthraquinone-2-carboxylic acid in nitrobenzene at 100 DEG  C.) is heated with 20 per cent aqueous ammonia, the amide is purified by crystallization from monochlorobenzene, the product is nitrated in conc. sulphuric acid with addition of paraformaldehyde at -5 DEG  C., and the nitro group is reduced with sodium sulphide to obtain 1 : 4-diaminoanthraquinone-2-carboxylic acid amide which gives powerful blue dyeings on acetate silk.  (2) 1-Methylaminoanthraquinone-2-nitrile (obtainable by action of cuprous cyanide on 1-methylamino-2-bromoanthraquinone in pyridine) is nitrated in conc. sulphuric acid at -5 DEG  C., with simultaneous saponification of the nitrile group to an amide group, and the nitro group is reduced with sodium sulphide; the product gives greenish blue dyeings on acetate silk.  (3) 4-Nitro-1-oxyanthraquinone-2-carboxylic acid chloride (obtainable by nitration of 1-oxyanthraquinone-2-carboxylic acid in monohydrate in presence of boric acid and treatment of the product with thionyl chloride in nitrobenzene at 90 DEG  C.) is heated with 20 per cent aqueous ammonia, whereafter the nitro group is reduced with sodium sulphide; the product gives violet dyeings on acetate silk.  (4) 1-Amino-4-nitroanthraquinone-2-carboxylic acid (obtainable by nitrating the formaldehyde compound of 1-aminoanthraquinone-2-carboxylic acid and saponifying the product with caustic soda) is heated with thionyl chloride in nitrobenzene, the product is treated with aqueous ammonia, and the nitro group is reduced with sodium sulphide or by vatting to obtain 1 : 4-diaminoanthraquinone-2-carboxylic acid amide.  (5) 1-Amino-4-p-toluenesulphonamidoanthraquinone-2-carboxylic acid is treated with thionyl chloride in nitrobenzene, the acid chloride so obtained is heated with aqueous ammonia, and the sulphonamide group is split off with conc. sulphuric acid to obtain 1 : 4-diaminoanthraquinone-2-carboxylic acid amide.  (6) 1-Amino-4-p-toluenesulphonamidoanthraquinone-2-carboxylic acid chloride is heated with 20 per cent aqueous methylamine solution, and the sulphonamide group is split off with conc. sulphuric acid to obtain 1 : 4-diaminoanthraquinone-2-carboxylic acid methylamide which gives on acetate silk more reddish dyeings than those of (1).  (7) 1-Amino-4-p-toluenesulphonamidoanthraquinone-2-carboxylic acid chloride is boiled with aniline, the carboxylic acid anilide is separated, dissolved in warm conc. sulphuric acid, and diluted with water to obtain 1 : 4-diaminoanthraquinone-2-carboxylic acid anilide which gives strong violet dyeings on acetate silk.