Chromium complex compounds, process for their manufacture and use thereof
The present invention relates to chromium complex compounds which, in the form of the free acid, have the formula ##STR2## wherein X is a direct bond or a bridge member, Z is a nitrogen atom or a--CH--group, each of p and q is independently 1 or 2, Y is an oxygen atom or a group of the formula --NR--, wherein R is hydrogen or a low molecular alkyl radical, with the proviso that, if Z is a CH group, Y must be an oxygen atom, R 1  is hydrogen or a substituent, B is a benzene or naphthalene radical, D is the radical of an o-hydroxyaldehyde and, if Z is the --CH--group or if Z is a nitrogen atom, D is the radical of a coupling component which couples in the ortho-position to Y, n is an integer from 2 to 8, preferably from 2 to 6, and A is a benzene or naphthalene radical or a substituted or unsubstituted aliphatic or cycloaliphatic radical, with the proviso that q must be 2 if A is an aliphatic or cycloaliphatic radical. 
     A bridge member X can be in particular a methylene bridge which is unsubstituted or substituted by low molecular alkyl, for example --CH 2  --, --C(CH 3 ) 2  --, ##STR3## or a bridge member of the formula --O--, --S--, --NR&#39;--, --SO--, --SO 2  --, --CO--, --CO--CO--, --CO--NH--, --NH--CO--NH--, --NH--CS--NH--, --SO 2  NH--, --SO 2  --NH--SO 2  --, --N═N--, --CH 2  --CH 2  -- or --CH═CH--, wherein R&#39; is hydrogen or low molecular alkyl. 
     In addition to hydrogen, the radical R 1  can be in particular the sulfo and carboxyl group, halogen, especially chlorine, and low molecular alkyl or alkoxy. 
     Throughout this specification, the term &#34;low molecular&#34; denotes radicals containing 1 to 5 carbon atoms. The radicals B can carry one or more sulfo groups and, in addition, be further substituted, for example by low molecular alkyl, alkoxy, alkylsulfonyl, sulfonamido, low molecular N-alkylsulfonamido or N,N-dialkylsulfonamido, chlorine, bromine, nitro, cyano, arylazo, especially phenylazo, sulfophenylazo or sulfonaphthylazo and arylazoarylene-azo, such as sulfophenylazophenylene-azo or sulfonaphthylazophenylene-azo. 
     The radical --D--Y-- is derived in particular from the following coupling components: phenols, naphthols, naphthylamines, pyrazolones, pyrazolimines, pyridones and acetoacetamides, especially acetoacetanilides, and barbituric acid derivatives and oxyquinolines. 
     The radicals A have either one of the meanings of B or they are derived from aliphatic or cycloaliphatic amino acids. In this latter case, q must be 2 and A is preferably a substituted or unsubstituted alkylene radical, an alkenylene or a cycloalkylene radical. An alkylene radical A contains preferably 1 to 11 carbon atoms and possible substituents are the hydroxyl, methylmercapto, methylsulfonyl or sulfo group, aryl radicals, in particular phenyl or substituted phenyl, for example hydroxyphenyl or phenyl which is substituted by low molecular alkyl or alkoxy, and finally heterocyclic radicals, such as imidazolyl or indolyl. An alkenylene radical A is for example the vinylene radical or the phenylvinylene radical. A cycloalkylene radical is in particular the cyclohexylene radical. 
     The α- and β-amino acids are particularly preferred, i.e. A is preferably a substituted or unsubstituted methylene or ethylene radical. Suitable amino acids are described, for example, in Greenstein and Winitz, Chemistry of Amino Acids, Wiley (1961). In particular, the invention relates to compounds of the formula (1), wherein Y is an oxygen atom or the --NH--group, and, most particularly, to chromium complexes which, in the form of the free acid, have the formula ##STR4## wherein X&#39; is a direct bond or a bridge of the formula ##STR5## --CH═CH--, --SO 2  -- or --SO 2  --NH--SO 2  --, Y&#39; is an oxygen atom or the --NH-- group, R 1  &#39; is hydrogen, the sulfo group, chlorine, methyl or methoxy, p is 1 or 2, q is 1 or 2, B&#39; is a phenyl or naphthyl radical which is unsubstituted or substituted by sulfo, arylazo, alkyl or alkoxy groups, chlorine, bromine, nitro or cyano, and D&#39; is a phenyl radical which is unsubstituted or substituted by hydroxyl, alkyl or alkoxy, a naphthyl radical which is unsubstituted or substituted by chlorine, acylamino or sulfo, the radical of a 1-aryl-3-methylpyrazol-5-one or the radical of an acetoacetanilide which is unsubstituted or substituted in the anilide nucleus by sulfo, nitro, chlorine, bromine, alkyl or alkoxy, and wherein A&#39;, if q is 1, has one of the meanings given for B&#39; or, if q is 2, is an alkylene group which is unsubstituted or substituted, for example, by hydroxyl, methylmercapto, methylsulfonyl, sulfo, phenyl, hydroxyphenyl, imidazolyl or indolyl. 
     By alkyl and alkoxy are meant in this connection low molecular radicals. Acylamino denotes low molecular alkanoylamino, alkylsulfonylamino and alkoxycarbonylamino radicals and aroylamino and arylsulfonylamino radicals, whilst the term aryl embraces in particular naphthyl, naphthyl substituted by 1 to 3 sulfo groups and also in particular phenyl and phenyl which is substituted by chlorine, bromine, methyl, ethyl, methoxy, nitro or sulfo. 
     The compounds of the present invention are obtained by reacting a compound of the formula ##STR6## wherein R 1 , X, Y, Z, A, B, D, p and q are as defined for formula (1), with a chromium donor to the 1:1 chromium complex or, in the case of the formula (4), to the chromium complex containing 2 atoms of chromium per molecule, and subsequently reacting this latter with the non-metallised compound of the formula (4) or (3), the starting materials being so chosen that they contain 2 to 8 sulfo groups. 
     The 1:1 chromium complex of the compound of the formula (3) is preferably prepared first and then reacted with the bisazomethine of the formula (4) in the ratio 2:1. Advantageously, this latter compound is prepared in the reaction mixture in situ. The procedure is that the 1:1 chromium complex of the compound of the formula (3) is reacted with a mixture of a dialdehyde of the formula ##STR7## and 2 equivalents of an amine or an amino acid of the formula ##STR8## wherein X, R 1 , q and A are as defined for formula (1). 
     A preferred group of the compounds of the present invention comprises those wherein X is a direct bond or a bridge member of the formula --SO 2  --, --CH 2  --, --CH═CH-- or --O--. 
     Preferred compounds are also those of the formula (2), wherein the radicals R 1  &#39; represent hydrogen or sulfo, as these compounds are particularly easy to obtain. 
     Particularly interesting compounds are also those of the formulae (1) and (2), wherein Q is 2 and A and A&#39; are aliphatic or cycloaliphatic radicals, in particular substituted or unsubstituted alkylene radicals. 
     If q is 2 in the compounds of the formula (2), A&#39; is preferably a phenyl radical which is substituted by nitro or sulfo or nitro and sulfo. 
     The starting compounds of the formula (3) are obtained in conventional manner. If Z is a nitrogen atom, an amine of the formula ##STR9## is diazotised and coupled to a coupling component of the formula 
     
         H--D--YH                                                   (8) 
    
     Examples of suitable diazo components of the formula (7) are: anthranilic acid, 4- or-5-sulfo- and 4- or-5-sulfonamidoanthranilic acid, 2-amino-1-hydroxybenzene, 4-chloro- and 4,6-dichloro-2-amino-1-hydroxybenzene, 4- or 5-nitro-2-amino-1-hydroxybenzene, 4-chloro- and 4-methyl- and 4-acetylamino-6-nitro-2-amino-1-hydroxybenzene, 6-acetylamino- and 6-chloro-4-nitro-2-amino-1-hydroxybenzene, 4-cyano-2-amino-1-hydroxybenzene, 4-methoxy-2-amino-1-hydroxybenzene, 2-amino-1-hydroxybenzene-5-methyl- and -5-benzylsulfone, 2-amino-1-hydroxybenzene-4-methyl-, -ethyl-, -chloromethyl- and -butylsulfone, 5-nitro- and 6-nitro-2-amino-1-hydroxybenzene-4-methylsulfone, 2-amino-1-hydroxybenzene-4- or -5-sulfonamide, 2-amino-1-hydroxybenzene-4- or -5-sulfo-N-methyl- and -sulfo-N-β-hydroxyethylamide, 2-amino-1-hydroxybenzene-4-sulfanilide, 4-methoxy-5-chloro-2-amino-1-hydroxybenzene, 4-methyl-2-amino-1-hydroxybenzene, 4-chloro-5-nitro-2-amino-1-hydroxybenzene, 3,4,6-trichloro-2-amino-1 -hydroxybenzene, 6-acetylamino-4-chloro-2-amino-1-hydroxybenzene, 4,6-dinitro-2-amino-1-hydroxybenzene, 4-nitro-2-amino-1-hydroxybenzene-6-sulfonamide, 2-amino-1-hydroxybenzene-4- or -5-sulfanthranilide, 2-amino-1-hydroxybenzene-4- or -5-sulfonic acid, 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid, 5-nitro- or 6-nitro-2-amino-1-hydroxybenzene-4-sulfonic acid, 1-amino-2-hydroxynaphthalene-4-sulfonic acid, 1-amino-2-hydroxy-6-nitronaphthalene-4-sulfonic acid, 4-(4&#39;- or 3&#39;-sulfophenylazo)-2-amino--hydroxybenzene, 4-(3&#39;-sulfonamidophenylazo)-2-amino-1-hydroxybenzene, 4-(4&#39;-phenylazophenylazo)-2-amino-1-hydroxybenzene, 2-amino-1-hydroxybenzene-4,6-disulfonic acid. 
     Instead of the above amines of the formula (7), suitable diazo components are also corresponding methoxy compounds, such as anisidine, 4- or 5-chloroanisidine, 4- or 5-nitroanisidine or anisidine-4- or 5-sulfonic acid, the methoxy group being converted during the chroming into an OH group. 
     Particularly interesting compounds are those wherein B and B&#39; are phenyl or naphthyl radicals which contain nitro and/or sulfo groups. 
     The radicals D and D&#39; are derived in particular from the following groups of coupling components: 
     Naphthols which are unsubstituted or substituted by chlorine, acylamino, amino, sulfo, sulfonamido, N-monosubstituted or N,N-disubstituted sulfonamido groups and sulfone groups, said groups having the same meanings as given previously. 
     Naphthylamines which are unsubstituted or substituted by sulfo, sulfonamido, mono- or disubstituted sulfonamido or sulfone groups. 
     5-Pyrazolones or 5-aminopyrazolones which in position 1  preferably contain a phenyl or naphthyl radical which is unsubstituted or substituted by chlorine, nitro, low molecular alkyl and alkoxy groups, sulfonamido, N-alkylated sulfonamide groups, sulfone or, in particular, sulfo groups. 
     Acetoacetanilides and benzoylacetanilides which can be substituted in the anilide nucleus by chlorine, bromine, low molecular alkyl, alkoxy, sulfone, sulfonamido, N-monosubstituted or N,N-disubstituted sulfonamido groups. 
     Phenols which are substituted by low molecular acylamino groups and/or alkyl groups preferably containing 1 to 5 carbon atoms and which couple in the ortho-position. 
     2,6-Dihydroxy-3-cyano- or -carbamoyl-4-alkylpyridine and 6-hydroxy-2-pyridones which in position 1 are substituted by low molecular substituted or unsubstituted alkyl, for example methyl, isopropyl, β-hydroxyethyl, β-aminoethyl or γ-isopropoxypropyl, and which in position 3 carry a cyano or carboxamido group and, in position 4, a low molecular alkyl group, in particular methyl. 
     Barbituric acid and barbituric acids which are substituted at the nitrogen atoms by low molecular alkyl or aryl, in particular phenyl. Dioxyquinolines. 
     Examples of such coupling components are: 
     2-naphthol, 1,3- or 1,5-dihydroxynaphthalene, 
     2-naphthol-6-β-hydroxyethylsulfone, 1-naphthol, 
     1-acetylamino-7-naphthol, 1-propionylamino-7-naphthol, 
     1-carbomethoxyamino-7-naphthol, 1-carboethoxyamino-7-naphthol, 1-carbopropoxyamino-7-naphthol, 1-dimethylaminosulfonyl-amino-7-naphthol, 6-acetyl-2-naphthol, 2-naphthol-3-, -4-, -5-, -6-, -7- or -8-sulfonic acid, 1-naphthol-3-, -4- or -5-sulfonic acid, 4-methyl-1-naphthol, 4-methoxy-1-naphthol, 4-acetyl-1-naphthol, 1-naphthol-3-, -4- or -5-sulfonamide, 2-naphthol-3-, -4-, -5-, -6-, -7- or -8-sulfonamide, 5,8-dichloro-1-naphthol, 5-chloro-1-naphthol, 2-naphthylamine, 2-naphthylamine-1-sulfonic acid, 1-naphthylamine-4- or -5-sulfonic acid, 2-aminonaphthalene-7-sulfonic acid, 1-naphthylamine-4-sulfonamide, 2-aminonaphthalene-6-sulfonamide, 2-phenylaminonaphthalene,2-(3&#39;-chlorophenyl)-aminonaphthalene, 2-aminonaphthalene-6-sulfonic acid N-methylamide or -6-sulfonic acid, 1,3-dimethylpyrazol-5-one, 3-methylpyrazol-5-one, 1-phenyl-3-methylpyrazol-5-one, 1-phenyl-5-pyrazolone-3-carbamoyl, 1-(2&#39;-, 3&#39; or 4&#39;-methylphenyl)-3-methylpyrazol-5-one, 1-[3&#39;- or 4&#39;-(β-hydroxyethylsulfonyl)-phenyl]-3-methylpyrazol-5-one, 1-(2&#39;, 3&#39;- or 4&#39; -sulfophenyl)-3-methylpyrazol-5-one, 1-(2&#39;-chloro-5&#39;-sulfophenyl)-3-methylpyrazol-5-one, 1-(2&#39;- or 4&#39;-methoxyphenyl)-3-methylpyrazol-5-one, 1-(2&#39;-, 3&#39;- or 4&#39;-chlorophenyl)-3-methylpyrazol-5-one, 1-(2&#39;-, 3&#39;- or 4&#39;-nitrophenyl)-3-methylpyrazol-5-one, 1-(2&#39;-, 5&#39;- or 3&#39;-, 4&#39;-dichlorophenyl)-3-methylpyrazol-5-one, 1-(2&#39;-, 3&#39;- or 4&#39;-sulfamoylphenyl)-3-methylpyrazol-5-one, 1-(2&#39;, 5&#39;-dichloro-4&#39;-sulfophenyl)-3-methylpyrazol-5-one, 1-(2&#39;-, 3&#39;- or 4&#39;-methylsulfonylphenyl)-3-methylpyrazol-5-one, 1-(2&#39;-, 3&#39;- or 4&#39;-sulfophenyl)-3-methyl-5-aminopyrazole, 1-(2&#39;-chloro-5&#39;-sulfophenyl)-3-methyl-5-aminopyrazole, acetoacetanilide, acetoacetanilide-4-sulfonic acid, acetoacet-o-anisidide, acetoacet-o-toluidide, acetoacet-o-chloroanilide, acetoacetanilide-3 or -4-sulfonamide, acetoacet-m-xylidide, tetralole, 4-methylphenol, 3-dialkylaminophenol, in particular 3-dimethylamino and 3-diethylaminophenol, 4-butylphenol, 4-amylphenol, in particular 4-t-amylphenol, 2-isopropyl-4-methylphenol, 2- or 3-acetylamino-4-methylphenol, 2-methoxycarbonylamino-4-methylphenol, 2-ethoxycarbonylamino-4-methylphenol and 3,4-dimethylphenol, resorcinol, 2,6-dihydroxy-3-cyano-4-methylpyridine, 1-methyl-3-cyano-4-ethyl-6-hydroxypyridone, 1-amino-3-cyano-4-methyl-6-hydroxypyridone, 1-phenyl-3-carbamoyl-4-methyl-6-hydroxypyridone, barbituric acid, 2,4-dihydroxyquinoline. 
     Preferably, D and D&#39; are naphthyl radicals which are unsubstituted or substituted by sulfo or amino and sulfo, or phenyl radicals which are unsubstituted or substituted by low molecular alkyl. 
     If Z is a --CH-- group, an amine of the formula (7) is reacted with an o-hydroxybenzaldehyde or o-hydroxynaphthaldehyde. Examples of suitable aldehydes are: 
     2-hydroxy-1-naphthaldehyde, 1-hydroxy-2-naphthaldehyde, 2-hydroxybenzaldehyde, 3- and 5-methyl-2-hydroxybenzaldehyde, 3,5-dimethyl-2-hydroxybenzaldehyde, 5-butyl-2-hydroxybenzaldehyde, 5-chloro- or 5-bromo-2-hydroxybenzaldehyde, 3-chloro-2-hydroxybenzaldehyde, 3,5-dichloro-2-hydroxybenzaldehyde, 5-sulfo-2-hydroxybenzaldehyde, 3-methyl-5-chloro-2-hydroxybenzaldehyde and the aldehyde derivatives thereof which are substituted by arylazo or arylazoarylene-azo. 
     The dialdehydes of the formula (5) are obtained by tetraazotising a diamine of the formula ##STR10## and coupling the resulting intermediate to 2 equivalents of salicylaldehyde. 
     Examples of suitable diamines of the formula (9) are: 
     4,4&#39;-diaminodiphenyl, 2,2&#39;-diaminodiphenyl-4,4&#39;-disulfonic acid, 4,4&#39;-diaminodiphenyl-3-sulfonic acid, 4,4&#39;-diaminodiphenyl-2,2&#39;- or 3,3&#39;-disulfonic acid, 4,4&#39;-diamino-3,3&#39;-dimethoxydiphenyl, 4,4&#39;-diamino-3,3&#39;- or 2,2&#39;-dimethyldiphenyl, 3,3&#39;- or 4,4&#39;-diaminodiphenylsulfone, 4,4&#39;-diaminobenzophenone, 4,4&#39;-diaminodiphenyl ether, 4,4&#39;-diaminodiphenylsilfide, 4,4&#39;-diaminodiphenylsulfoxide, 4,4&#39;-diaminodiphenylamine, 4,4&#39;-diaminodiphenyl-2-sulfonic acid, 4,4&#39;-diaminobenzile, 3,3&#39;- or 4,4&#39;-diaminobenzanilide, 3,3&#39;-diamino-benzanilide-4-sulfonic acid, 4,4&#39;-diaminobenzanilide-3-sulfonic acid, 3,3&#39;- or 4,4&#39;-diaminodiphenyl urea, 4,4&#39;-diaminodiphenyl urea-3,3&#39;-disulfonic acid, 4,4&#39;-diaminodiphenyl thiourea, 4,4&#39;-diaminobenzene sulfanilide, 3,3&#39;- or 4,4&#39;-diaminodiphenyldisulfimide, 4,4&#39;-dichloro-3,3-diaminodiphenyldisulfimide, 4,4&#39;-diaminoazobenzene, 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid, 4,4&#39;-diamino-diphenylmethane, 4,4&#39;-diamino-3,3&#39;-dimethyldiphenylmethane, 3,3&#39;-diamino-4,4&#39;-dimethyldiphenylmethane, 4,4&#39;-diaminotriphenylmethane, 4,4&#39;-diaminodiphenylethane, 4,4&#39; -diamino-3,3&#39;-dimethyldiphenylethane, 2,2-bis-(4&#39;-aminophenyl)-propane, 1,1-bis-(4&#39;-aminophenyl)-cyclohexane and 1,1-bis-(4&#39;-amino-3&#39;-methylphenyl)-cyclohexane. 
     The bisazomethine is prepared by condensing the dialdehyde of the formula (5) with 2 equivalents of an amine or of an amino acid of the formula (6). Suitable compounds of the formula (6) are, on the one hand, the same aromatic amines as cited in connection with the diazo components of the formula (7), and, on the other hand, aliphatic or cycloaliphatic amino acids. 
     Examples of such amino acids are: glycine, α-alanine, β-alanine, 4-aminobutyric acid, 5-aminovaleric acid, 6-aminocapronic acid, 7-aminoheptanoic acid, 8-aminocaprylic acid, 11-aminoundecanoic acid, 12-aminolauric acid, serine, 5-benzylcysteine, phenylglycine, phenylalanine, norleucine, norvaline, leucine, lysine, methionine, methioninesulfone, threonine, histidine, tryptophane, tyrosine, 2-aminocyclohexanecarboxylic acid. 
     It is advantageous not to isolate the bisazomethane, but to prepare it in situ in the same reaction mixture in which it is added to the 1:1 chromium complex of the compound of the formula (3). 
     Particularly preferred amino acids of the formula (6) are glycine and α- and β-alanine. Preferred aromatic amines of the formula (6) are in particular those wherein q is 1 and A is a phenylene radical which is substituted by nitro and/or sulfo. 
     Preferably the starting products are so chosen that the resulting complex contains 2 to 6 sulfo groups. 
     The manufacture of the 1:1 chromium complex of the compound of the formula (3) or (4) is carried out by conventional methods which are known per se, for example by reacting said compound in an acid medium with a salt of trivalent chromium, for example chromium formiate, chromium sulfate, chromium chloride hexahydrate or chromium fluoride, at boiling temperature or, if appropriate, at temperatures exceeding 100° C. Trivalent chromium can also be obtained in the reaction mixture from chromium (VI) compounds, for example chromate, by simultaneously adding a reducing agent. The metallising can be carried out in an aqueous, aqueous-organic or in pure organic solvents, such as alcohols or ketones, with or without the addition of solution promoters or chroming catalysts. 
     The reaction of the 1:1 chromium complex of the compound of the formula (3) or (4) with the metal-free compounds of the formulae (4) or (3), and the reaction between a 1:1 chromium complex of a compound of the formula (3), an amine or an amino acid of the formula (6) and a dialdehyde of the formula (5), is advantageously carried out in a neutral to weakly alkaline medium, in an open or closed apparatus, at elevated temperature, for example at temperatures between 50° and 120° C. 
     The process can be carried out in organic solvents, for example alcohols or ketones or in an aqueous solution, in which case, if appropriate, the addition of solvents, for example of alcohols, formamide etc., can promote the reaction. It is usually advisable to react as far as possible equivalent amounts of the chromium-containing 1:1 complex and of the metal-free dye. An excess of metal-containing dye is usually less disadvantageous than one of metal-free dye. 
     Instead of using a homogeneous 1:1 chromium complex, it is also possible to use a mixture of different chromium complexes or a mixture of different dialdehydes and amines. 
     The chromium-containing mixed complexes of the present invention which are obtained by the above process are isolated with advantage in the form of their salts, in particular their alkali, for example lithium, salts, in particular sodium salts, or also ammonium salts. They are suitable for dyeing a very wide variety of polyamide materials, such as wool, synthetic polyamide fibres and, in particular, for dyeing leather. Depending on their constitution, they are also suitable for dyeing cellulosics, for example cotton and paper. 
     The compounds of the present invention are productive and have good covering power. They have a good exhaustion capacity while at the same time having good fastness properties, such as fastness to washing, water, perspiration, rubbing, diffusion, light and alkali. Their good build-up on different types of leather, both on pure chrome-tanned leather and on leather which has been retanned with vegetable or synthetic tannins, is to be particularly mentioned. Strong, orange or brown and olive shades are obtained. 
     The invention is illustrated by the following Examples, in which the parts and percentages are by weight unless otherwise indicated. 
    
    
     EXAMPLE 1 ##STR11## 41.9 parts of the monoazo dye obtained from diazotised 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and 1-phenyl-3-methyl-5-pyrazolone are stirred with 26.7 parts of chromium chloride hexahydrate in 750 parts by volume of ethylene glycol at 120°-125° C. until the starting material can no longer be detected. Then 23.4 parts of 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and 31.8 parts of the coupling product obtained from tetraazotised 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid and salicylaldehyde are added at 80°-85° C. to the resulting solution of the 1:1 chromium complex and the reaction mixture is kept at this temperature until the addition is complete. The pH of the reaction mixture is adjusted to 7-7.5 by addition of 5 N sodium hydroxide and kept thereat. The chromium-containing dye is precipitated by adding saturated sodium chloride solution, collected by filtration and cautiously dried. 
     The product is a dark powder which dissolves in water to give an orange solution and dyes leather in orange shades of good general fastness properties. 
     EXAMPLE 2 ##STR12## 43.9 parts of the 1:1 chromium complex corresponding to 5.2 parts of chromium and 38.9 parts of the monoazo dye obtained from diazotised 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and 2-hydroxynaphthalene are suspended in 1000 parts by volume of water with 23.4 parts of 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and 31.8 parts of the disazo dye obtained from 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid and salicylaldehyde. The reaction mixture is heated to 80°-85° C. while simultaneously raising the pH of the suspension to 7-7.5 with 5 N sodium hydroxide and is kept at this temperature and at constant pH with further 5 N sodium hydroxide until the starting materials can no longer be detected. The chromium-containing dye is precipitated with sodium chloride, collected by filtration, washed with dilute sodium chloride solution and dried, yielding a dark powder which dissolves in water to form a brown solution and colours leather in brown shades of good general fastness properties. 
     EXAMPLE 3 ##STR13## 58.4 parts of the 1:1 chromium complex corresponding to 5.2 parts of chromium and 53.4 parts of the monoazo dye obtained from diazotised 6-nitro-1-amino-2-hydroxynaphthalene-4-sulfonic acid and 2-amino-5-hydroxynaphthalene-7-sulfonic acid, 13.7 parts of 2-aminobenzoic acid and 31.8 parts of the disazo dye obtained from 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid and salicylaldehyde are suspended in 750 parts by volume of water. The mixture is then heated to 80°-85° C. while raising the pH of the suspension to 7-7.5 with 5 N sodium hydroxide and is kept at this temperature and at constant pH with further 5 N sodium hydroxide until the starting materials can no longer be detected. The chromium-containing dye is then precipitated with sodium chloride, collected by filtration and dried, yielding a dark powder which dissolves in water to give an olive solution and dyes leather in olive shades. 
     EXAMPLE 4 ##STR14## 58.4 parts of the 1:1 chromium complex corresponding to 5.2 parts of chromium and 53.4 parts of the monoazo dye obtained from diazotised 6-nitro-1-amino-2-hydroxynaphthalene-4-sulfonic acid and 2-amino-5-hydroxynaphthalene-7-sulfonic acid, 18.9 parts of 2-amino-1-hydroxybenzene-4-sulfonic acid and 31.8 parts of the disazo dye obtained from 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid and salicylaldehyde are suspended in 750 parts by volume of water. The mixture is then heated to 80°-85° C. while raising the pH of the solution to 7-7.5 with 5 N sodium hydroxide and is kept at this temperature and at constant pH with further 5 N sodium hydroxide until the starting materials can no longer be detected. The chromium-containing dye is isolated by concentrating the solution, and then dried. It is a dark powder which dyes leather from an acid bath in brown shades of good general fastness properties. 
     Table I lists further dyes having similar properties which are obtained by reacting the 1:1 chromium complex of the compounds in column III with the amines of column II and the aldehydes of column I. Column IV indicates the shade in which these dyes colour leather. 
     
                                           TABLE I                                 
__________________________________________________________________________
No.                                                                       
   I               II          III                      IV                
__________________________________________________________________________
    ##STR15##                                                             
                    ##STR16##                                             
                                ##STR17##               yellowish orange  
2  &#34;                                                                      
                    ##STR18##  &#34;                        yellowish orange  
3  &#34;                                                                      
                    ##STR19##                                             
                                ##STR20##               brown             
4  &#34;                                                                      
                    ##STR21##                                             
                                ##STR22##               brown             
5  &#34;                                                                      
                    ##STR23##                                             
                                ##STR24##               brown             
6  &#34;                                                                      
                    ##STR25##                                             
                                ##STR26##               brown             
7  &#34;                                                                      
                    ##STR27##                                             
                                ##STR28##               olive- brown      
8  &#34;               &#34;                                                      
                                ##STR29##               brown             
9  &#34;                                                                      
                    ##STR30##  &#34;                        brown             
10 &#34;               &#34;                                                      
                                ##STR31##               brown             
11 &#34;                                                                      
                    ##STR32##                                             
                                ##STR33##               orange            
12 &#34;               &#34;                                                      
                                ##STR34##               brown             
13                                                                        
    ##STR35##                                                             
                    ##STR36##                                             
                                ##STR37##               olive- brown      
14 &#34;               &#34;                                                      
                                ##STR38##               brown             
15                                                                        
    ##STR39##      &#34;           &#34;                        brown             
16 &#34;               &#34;                                                      
                                ##STR40##               olive- brown      
17                                                                        
    ##STR41##                                                             
                    ##STR42##  &#34;                        olive- brown      
18                                                                        
    ##STR43##                                                             
                    ##STR44##                                             
                                ##STR45##               brown             
19 &#34;               &#34;                                                      
                                ##STR46##               brown             
20 &#34;               &#34;                                                      
                                ##STR47##               brown             
21                                                                        
    ##STR48##                                                             
                    ##STR49##                                             
                                ##STR50##               greenish olive    
22 &#34;                                                                      
                    ##STR51##                                             
                                ##STR52##               orange            
23 &#34;                                                                      
                    ##STR53##  &#34;                        orange            
24 &#34;                                                                      
                    ##STR54##  &#34;                        orange            
25 &#34;                                                                      
                    ##STR55##                                             
                                ##STR56##               brown             
26 &#34;                                                                      
                    ##STR57##  &#34;                        brownish olive    
27 &#34;                                                                      
                    ##STR58##                                             
                                ##STR59##               olive             
28 &#34;               &#34;                                                      
                                ##STR60##               orange            
29 &#34;               &#34;                                                      
                                ##STR61##               olive             
30                                                                        
    ##STR62##                                                             
                    ##STR63##                                             
                                ##STR64##               reddish orange    
31 &#34;               &#34;                                                      
                                ##STR65##               reddish orange    
32                                                                        
    ##STR66##                                                             
                    ##STR67##                                             
                                ##STR68##               brown             
33 &#34;                                                                      
                    ##STR69##  &#34;                        brown             
34                                                                        
    ##STR70##                                                             
                    ##STR71##                                             
                                ##STR72##               orange            
35 &#34;               &#34;                                                      
                                ##STR73##               brown             
36                                                                        
    ##STR74##                                                             
                    ##STR75##                                             
                                ##STR76##               olive             
37 &#34;                                                                      
                    ##STR77##  &#34;                        olive brown       
38                                                                        
    ##STR78##                                                             
                    ##STR79##  &#34;                        olive brown       
39 &#34;               &#34;                                                      
                                ##STR80##               orange            
40                                                                        
    ##STR81##                                                             
                    ##STR82##                                             
                                ##STR83##               olive             
41 &#34;                                                                      
                    ##STR84##                                             
                                ##STR85##               brown             
42                                                                        
    ##STR86##                                                             
                    ##STR87##                                             
                                ##STR88##               brown             
43 &#34;               &#34;                                                      
                                ##STR89##               olive             
44                                                                        
    ##STR90##                                                             
                    ##STR91##                                             
                                ##STR92##               olive             
45 &#34;               &#34;                                                      
                                ##STR93##               orange            
46                                                                        
    ##STR94##      &#34;           &#34;                        olive             
47 &#34;               &#34;                                                      
                                ##STR95##               brown             
48 &#34;                                                                      
                    ##STR96##                                             
                                ##STR97##               olive brown       
49 &#34;               &#34;                                                      
                                ##STR98##               olive             
50                                                                        
    ##STR99##                                                             
                    ##STR100##                                            
                                ##STR101##              brown             
51 &#34;               &#34;                                                      
                                ##STR102##              olive             
52 &#34;               &#34;                                                      
                                ##STR103##              orange            
53 &#34;                                                                      
                    ##STR104##                                            
                                ##STR105##              brown             
54 &#34;               &#34;                                                      
                                ##STR106##              brown             
55 &#34;                                                                      
                    ##STR107##                                            
                                ##STR108##              brown             
                                ##STR109##                                
56 &#34;               &#34;                                                      
                                ##STR110##              olive             
57 &#34;               &#34;                                                      
                                ##STR111##              brown             
58 &#34;               &#34;                                                      
                                ##STR112##              orange            
59 &#34;               &#34;                                                      
                                ##STR113##              orange            
60 &#34;               &#34;                                                      
                                ##STR114##              olive brown       
61 &#34;               &#34;                                                      
                                ##STR115##              olive             
__________________________________________________________________________
                                                        brown             
 
    
     EXAMPLE 5 ##STR116## 43.9 parts of the 1:1 chromium complex corresponding to 5.2 parts of chromium and 38.9 parts of the monoazo dye obtained from diazotised 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and 2-hydroxynaphthalene, 7.5 parts of glycine and 31.8 parts of the disazo dye obtained from 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid and salicylaldehyde are suspended in 850 parts by volume of water. The reaction mixture is heated to 80°-85° C. while simultaneously raising the pH to 7-7.5 with 5 N sodium hydroxide and is kept at this temperature and at constant pH with further 5 N sodium hydroxide until the starting materials can no longer be detected. The chromium dye is precipitated with sodium chloride, collected by filtration, washed with dilute sodium chloride solution and dried, yielding a dark powder which dissolves in water to give a brown solution and dyes leather in brown shades of good general fastness properties. 
     EXAMPLE 6 ##STR117## 43.9 parts of the 1:1 chromium complex corresponding to 5.2 parts of chromium and 38.9 parts of the monoazo dye obtained from 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and 2-hydroxynaphthalene, 8.9 parts of β-alanine and 31.8 parts of the disazo dye obtained from 4,4&#39;-diaminostilbene-2,2&#39;-disulfonic acid and salicylaldehyde are suspended in 850 parts by volume of water. The reaction mixture is heated to 80°-85° C. while simultaneously raising the pH to 7-7.5 with 5 N sodium hydroxide and is kept at this temperature and at constant pH with further 5 N sodium hydroxide until the starting materials can no longer be detected. The chromium dye is precipitated with sodium chloride, collected by filtration, washed with dilute sodium chloride solution and dried, yielding a dark powder which dissolves in water to give a brown solution and dyes leather in brown shades of good fastness properties. 
     EXAMPLE 7 ##STR118## 48.9 parts of the 1:1 chromium complex corresponding to 5.2 parts of chromium and 43.9 parts of the monoazo dye obtained from diazotised 6-nitro-1-amino-2-hydroxynaphthalene-4-sulfonic acid and 2-hydroxynaphthalene, 30.5 parts of the coupling product obtained from diazotised 4,4&#39;-diaminodiphenyl-2,2&#39;-disulfonic acid and salicylaldehyde and 7.5 parts of glycine are suspended in 850 parts of water. The mixture is heated to 80°-85° C. while simultaneously raising the pH of the suspension to 7-7.5 with 5 N sodium hydroxide and is kept at this temperature and at constant pH with further 5 N sodium hydroxide until the starting materials can no longer be detected. The chromium-containing dye is precipitated with sodium chloride, collected by filtration and dried, yielding a dark powder which dissolves in water to give an olive solution and dyes leather in olive shades. 
     Table II lists further dyes with similar properties which are obtained by reacting the 1:1 chromium complexes of the compounds of column III with the amino acids of column V and the aldehydes of column I. The shades in which these dyes colour leather are indicated in column IV. 
     
                                           TABLE II                                
__________________________________________________________________________
No.                                                                       
   I                II       III                      IV                  
__________________________________________________________________________
    ##STR119##                                                            
                     ##STR120##                                           
                              ##STR121##              brown               
2. &#34;                &#34;                                                     
                              ##STR122##              orange              
3. &#34;                                                                      
                     ##STR123##                                           
                             &#34;                        orange              
4. &#34;                                                                      
                     ##STR124##                                           
                              ##STR125##              orange              
5. &#34;                                                                      
                     ##STR126##                                           
                             &#34;                        orange              
6. &#34;                                                                      
                     ##STR127##                                           
                              ##STR128##              olive               
7. &#34;                                                                      
                     ##STR129##                                           
                              ##STR130##              brown               
8. &#34;                                                                      
                     ##STR131##                                           
                             &#34;                        brown               
9. &#34;                                                                      
                     ##STR132##                                           
                             &#34;                        brown               
10.                                                                       
    ##STR133##                                                            
                     ##STR134##                                           
                             &#34;                        olive- brown        
   &#34;                                                                      
                     ##STR135##                                           
                             &#34;                        &#34;                   
    ##STR136##                                                            
                     ##STR137##                                           
                              ##STR138##              olive               
   &#34;                &#34;                                                     
                              ##STR139##              olive               
    ##STR140##      &#34;                                                     
                              ##STR141##              orange              
   &#34;                                                                      
                     ##STR142##                                           
                             &#34;                        &#34;                   
    ##STR143##                                                            
                     ##STR144##                                           
                             &#34;                        orange              
   &#34;                                                                      
                     ##STR145##                                           
                             &#34;                        orange              
    ##STR146##                                                            
                     ##STR147##                                           
                             &#34;                        orange              
   &#34;                                                                      
                     ##STR148##                                           
                             &#34;                        &#34;                   
20.                                                                       
    ##STR149##      &#34;        &#34;                        orange              
   &#34;                                                                      
                     ##STR150##                                           
                             &#34;                        orange              
    ##STR151##                                                            
                     ##STR152##                                           
                              ##STR153##              brown               
   &#34;                &#34;                                                     
                              ##STR154##              olive               
   &#34;                &#34;                                                     
                              ##STR155##              orange              
   &#34;                &#34;                                                     
                              ##STR156##              orange              
    ##STR157##                                                            
                     ##STR158##                                           
                              ##STR159##              olive               
   &#34;                                                                      
                     ##STR160##                                           
                             &#34;                        brown               
   &#34;                &#34;                                                     
                              ##STR161##              olive               
   &#34;                                                                      
                     ##STR162##                                           
                              ##STR163##              brown               
30.                                                                       
   &#34;                                                                      
                     ##STR164##                                           
                             &#34;                        brown               
   &#34;                                                                      
                     ##STR165##                                           
                             &#34;                        brown               
   &#34;                                                                      
                     ##STR166##                                           
                              ##STR167##              olive- green        
   &#34;                                                                      
                     ##STR168##                                           
                              ##STR169##              orange              
   &#34;                                                                      
                     ##STR170##                                           
                             &#34;                        orange              
   &#34;                                                                      
                     ##STR171##                                           
                              ##STR172##              orange              
   &#34;                                                                      
                     ##STR173##                                           
                             &#34;                        orange              
    ##STR174##                                                            
                     ##STR175##                                           
                              ##STR176##              orange              
   &#34;                                                                      
                     ##STR177##                                           
                             &#34;                        orange              
    ##STR178##                                                            
                     ##STR179##                                           
                             &#34;                        orange              
40.                                                                       
   &#34;                &#34;                                                     
                              ##STR180##              orange              
   &#34;                &#34;                                                     
                              ##STR181##              olive- brown        
   &#34;                &#34;                                                     
                              ##STR182##              olive- brown        
   &#34;                &#34;                                                     
                              ##STR183##              olive               
   &#34;                &#34;                                                     
                              ##STR184##              brown               
                              ##STR185##              brown               
__________________________________________________________________________
 
    
     DYEING PROCEDURE FOR LEATHER 
     100 parts of clothing velours leather (dry weight) are wet back at 50° C. for 2 hours in a solution of 1000 parts of water and 2 parts of 24% ammonia and subsequently dyed for 1 hour at 60° C. in a solution of 1000 parts of water, 2 parts of 24% ammonia and 6 parts of the dye of Example 7. A solution of 40 parts of water and 4 parts of 85% formic acid is then added and dyeing is continued for a further 30 minutes. The leather is then thoroughly rinsed and, if appropirate, treated for 30 minutes at 50° C. with 2 parts of a dicyandiamine/formaldehyde condensation product. Other kinds of velour leather as well as glove leather can be dyed in the same manner. 
     The resulting olive dyeings are distinguished by good fastness properties and good covering power. 
     A fast, brown dyeing is obtained in the same manner using the dye of Example 2.