Patent GB-380078-A (GB)
Title: Process for the preparation of new dyestuffs of the anthraquinone series
Filed: 1931-06-05
Abstract: Anthrapyridone derivatives which are water-soluble dyes are prepared by introducing one or more sulphonic groups in known manner into anthrapyridones of the formula: <FORM:0380078/IV/1> wherein R represents penhyl, alkyl or alkoxy, R1 represents hydrogen or alkyl, X represents hydrogen, alkyl, alkoxy or halogen, Y represents hydrogen, -NH-aryl or -NH-cycloalkyl, Z represents hydrogen, -NH-aryl or -NH-cycloalkyl groups and wherein of Y and Z at least one represents a -NH-aryl or a -NH-cycloalkyl residue.  The products differ according to the sulphonation method employed; thus sulphuric acid monohydrate or fuming sulphuric acid may be used at different temperatures, or in the case when X represents a halogen it may be replaced by a sulpho group by treatment with sulphite in the usual way.  By combining these different sulphonation methods products containing sulpho groups in the aryl and anthrone residues may be obtained.  The products dye fast bright yellow to blue-red and violet shades on wool.  In examples: (1) C-carbethoxy-2-bromo-4-phenylaminoanthrapyridone is treated with monohydrate to give a violet dye; by using free sulphuric anhydride further sulpho group enters the molecule; the same starting material before or after such sulphonation may be treated with aqueous potassium sulphite and phenol to replace the 2-bromo atom by a sulpho group; the corresponding bases derived from m-toluidine and m-chloraniline behave in a similar way, but those derived from p-toluidine, p-chloraniline, xylidine, anisidine, cresidine yield the same product by sulphonation with monohydrate or oleum: (2) C-carbethoxy-2-methyl-4-p-chloranilidoanthrapyridone is sulphonated with weak oleum at 40 DEG  C. to give a blueish-red dye; sulphonation at 70 DEG  C. gives a yellowish red dye, probably a C-carboxy derivative of the anthrapyridone; it is stated that this capacity to form two series of sulphonation products is confined to the C-carbethoxy derivatives; corresponding bases derived from p-toluidine, dichloraniline, isomeric toluidines or chloranilines, xylidines, anisidines may be sulphonated in the same way: (3) C-acetyl-2-bromo-4-m-xylidinoanthrapyridone is sulphonated with weak oleum to give a violet-red dye; the corresponding bases derived from aniline, m-toluidine and m-chloraniline furnish mono-and disulphonated products by similar sulphonation; by treating the above starting material with aqueous sulphite and phenol under pressure a reddish-violet dye is obtained; when the corresponding base from aniline is used a red-violet dye is also obtained whereas the bases from anisidine, cresidine or naphthylamine yield violet dyes: (4) C-carbethoxy-4-p-chloranilidoanthrapyridone is sulphonated by monohydrate to give a blueish-red dye: (5) C-carbethoxy-N-methyl-4-p-phenylenediaminoanthrapyridone is sulphonated by monohydrate to give a violet dye: (6) C-carbethoxy-5-p-toluidinoanthrapyridone is sulphonated by a monohydrateoleum mixture to give a brownish bordeaux dye: (7) C-carbethoxy - 2 - bromo-4 - cyclohexylaminoanthrapyridone is treated with sulphite and phenol to give a blueish-red dye.  The starting materials may be prepared by condensing the appropriate halogenated anthrapyridones with aromatic or hydroaromatic bases (cf. Specifications 377,419 and 377,632).