4,4'-Diazobenzanilide Dyestuffs

Abstract

The present invention provides 4,4′-diazobenzanilide derivatives, a process for their preparation, their use as dyes, dyed paper, formulations comprising them and also precursors thereof and their processes of preparation.

Description

The present invention refers to 4,4′-diazobenzanilide derivatives, to a process for their preparation, to their use as dyes, to dyed paper, to formulations comprising them and also to precursors thereof and their processes of preparation.

4,4′-Diazobenzanilide derivatives are common dyes.

WO 03/10433 describes 4,4′-diazobenzanilide derivatives which are derived from 4,4′-di-amino-3′-sulfobenzanilide, 4,4′-diamino-2′-methoxy-5′-sulfobenzanilide, 3,4′-diamino-3′-sulfobenzanilide, 3,4′-diamino-2′-methoxy-5′-sulfobenzanilide, 4,3′-diamino-4′-sulfobenzanilide, 3,3′-diamino-4′-sulfobenzanilide, 4,4′-diamino-2′,5′-disulfobenzanilide, 3,4′-diamino-2′,5′-disulfobenzanilide, 4,4′-diamino-3′-carboxybenzanilide or 3,4′-diamino-3′-carboxybenzanilide.

DE 2 236 250 A1 describes 4,4′-diazobenzanilide derivatives which are derived from 4,4′-diaminobenzanilide, 4,4′-diamino-2′-methoxybenzanilide, 4,4′-diamino-2′-chlorobenzanilide, 4,4′-diamino-2′-chlorobenzanilide, 4,4′-diamino-2′-methylbenzanilide or 4,4′-diamino-2′,6′-dichlorobenzanilide.

EP 0 262 095 describes 4,4′-diazobenzanilide derivatives of the formula

in which T¹ is hydrogen, methyl or NHCOCH₃, T² is hydrogen, methyl or methoxy, T³ is NHCN or NHCONH₂ and the sulfogroups are in 6, 8 or 5,7-position. The disadavantage of these 4,4′-diazobenzanilide derivatives is that their synthesis involves the use of toxic o-anisidine or p-cresidine derivatives.

It is an object of the present invention to provide 4,4′-diazobenzanilide derivatives, which can be used as dyes of yellow or orange shade for dyeing natural or synthetic materials, especially paper, and which can be synthesized from ecological harmless starting materials. In addition, the 4,4′-diazobenzanilide derivatives should show excellent colour strength, lightfastness and substantivity, whilst being sufficient water-soluble to be employed as an aqueous formulation.

This object is solved by the 4,4′-diazobenzanilide derivatives according to claim 1, the 4-amino-4′-azobenzanilide derivatives according to claim 2, the processes according to claims 3, 4 and 5, the paper according to claim 9 and by formulations according to claims 10 and 11.

The 4,4′-diazobenzanilide derivative of the present invention has formula

in whichA¹ represents phenyl or 1- or 2-naphthyl, whereby phenyl can be unsubstituted or mono- or disubstituted with sulfo, C_1-4-alkyl, C_1-4-alkoxy, C_2-4-hydroxyalkoxy, halogen, hydroxy, amino, acetamido, ureido or carboxy, and whereby 1- or 2-naphthyl can be unsubstituted or substituted with one or more sulfo groups, and

A² represents a residue selected from the group consisting of

in which

Z¹ represents C_1-4-alkyl or phenyl, whereby phenyl may be unsubstituted or mono-substituted with C_1-4-alkyl, C_1-4-alkoxy or halogen, and

Z² represents phenyl or 1- or 2-naphthyl, whereby phenyl may be unsubstituted or mono-, di- or trisubstituted with sulfo, C_1-4-alkyl, C_1-4-alkoxy, C_2-4-hydroxyalkoxy, halogen, hydroxy, amino, acetamido, ureido or carboxy and whereby 1- or 2-naphthyl may be unsubstituted or mono- or disubstituted with sulfo or carboxy,

Y represents O, N—CN or N—CONH₂,

Q¹ represents hydrogen, hydroxy, C_1-2-alkyl, hydroxyethyl, C_1-2-alkoxy, carboxy, carbamoyl, C_1-2-alkoxycarbonyl, and

Q² represents hydrogen, cyano, halogen, sulfo, C_1-2-alkyl or carbamoyl, whereby C_1-2-alkyl may be unsubstituted or substituted with hydroxy, phenyl or sulfo, and

Q³ represents hydrogen, phenyl, C_1-2-alkylphenyl, C_1-4-alkyl, whereby C_1-4-alkyl may be unsubstituted or substituted with hydroxy, cyano, C_1-2-alkoxy or sulfo, and

Q⁴ represents hydrogen or hydroxy,

R⁵ represents hydrogen, C_1-4-alkyl, C_2-4-alkenyl, carboxy, NHCOC_1-4-alkyl, and

R⁶ and R⁷ each independently from each other represent hydrogen, halogen, sulfo, C_1-4-alkyl or carboxy, and

R⁸ represents hydrogen or C_1-4-alkyl,

R⁹ represents hydrogen, C_1-4-alkyl, and

R¹⁰ represents hydrogen or hydroxy,

R¹¹ and R¹² each independently from each other represent hydrogen, C_1-4-alkyl, C_1-4-alkoxy, hydroxy, halogen, amino, acetamido, sulfo, carboxy, C_1-4-alkoxycarbonyl or C_1-4-alkylaminocarbonyl, and

R² represents hydrogen, C_1-4-alkyl, C_1-4-alkoxy, halogen, hydroxy, carboxy, acetamido, ureido or sulfo, whereby C_1-4-alkyl and C_1-4-alkoxy may be unsubstituted or substituted by halogen, hydroxy, carboxy, acetamido, ureido or sulfo, and

R³ and R⁴ each independently from each other represent hydrogen, C_1-4-alkyl, C_1-4-alkoxy, halogen, hydroxy, carboxy, amino, C_1-4-alkylamino, acetamido or ureido, whereby C_1-4-alkyl and C_1-4-alkoxy may be unsubstituted or substituted by halogen, hydroxy, carboxy, amino, C_1-4-alkylamino, acetamido or ureido, and

R^1A represents a residue selected from the group consisting of

in whichn≧1,

A¹, A², R², R³ and R⁴ have the meaning as indicated above, and

X represents C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, NH or S.

C_1-4-Alkyl can be methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl or isobutyl. C_1-4-alkoxy can be methoxy, ethoxy, propoxy, isopropoxy, butoxy, sec-butoxy, tert-butoxy or isobutoxy. C_2-4-hydroxyalkoxy can be 2-hydroxyethoxy, 3-hydroxypropoxy, 2-hydroxypropoxy, 1-hydroxyisopropoxy or 4-hydroxybutoxy. Halogen can be fluorine, bromine, chlorine or iodine. C_1-2-alkyl is methyl or ethyl. C_1-2-alkoxy is methoxy or ethoxy. C_1-2-alkoxycarbonyl is methoxycarbonyl or ethoxycarbonyl. C_1-2-alkylphenyl can be o-, m- or p-tolyl or 2-, 3-, or 4-ethylphenyl. C_2-4-alkenyl can be vinyl, 1-propenyl, allyl, 1-butenyl or 2-butenyl. NHCOC_1-4-alkyl can be acetamido, propionylamino or butyrylamino. C_1-4-alkylaminocarbonyl can be methylaminocarbonyl, ethylaminocarbonyl, propylaminocarbonyl, butylaminocarbonyl, tert-butylaminocarbonyl or isobutylaminocarbonyl. C_1-4-Alkylamino can be methylamino, ethylamino, propylamino, isopropylamino, butylamino, sec-butylamino, tert-butylamino or isobutylamino. C_2-14-alkylene can be ethylene, trimethylene, propylene, tetramethylene, ethylethylene, pentamethylene, hexamethylene, heptamethylene or octamethylene. Examples of a C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, are —CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂—, —CH₂CH₂—O—CH₂CH₂—, —CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂— and —CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂—.

In preferred 4,4′-diazobenzanilide derivatives 1A

A¹ represents phenyl or 1- or 2-naphthyl, whereby phenyl and 1- or 2-naphthyl are substituted with at least one sulfo group, and whereby phenyl may additionally be mono-substituted with C_1-4-alkyl, C_1-4-alkoxy, C_2-4-hydroxyalkoxy, halogen, hydroxy, acetamido, ureido or carboxy, and

A² represents a residue selected from the group consisting of

in which

Z¹ represents C_1-4-alkyl or phenyl, whereby phenyl may be unsubstituted or mono-substituted with C_1-4-alkyl, C_1-4-alkoxy or halogen, and

Z² represents phenyl or 1- or 2-naphthyl, whereby phenyl may be unsubstituted or mono-, di- or trisubstituted with sulfo, C_1-4-alkyl, C_1-4-alkoxy, C_2-4-hydroxyalkoxy, halogen, hydroxy, amino, acetamido, ureido or carboxy and whereby 1- or 2-naphthyl may be unsubstituted or mono- or disubstituted with sulfo or carboxy,

Y represents O, N—CN or N—CONH₂,

Q¹ represents hydrogen, hydroxy, C_1-2-alkyl, hydroxyethyl, C_1-2-alkoxy, carboxy, carbamoyl, C_1-2-alkoxycarbonyl, and

Q² represents hydrogen, cyano, halogen, sulfo, C_1-2-alkyl or carbamoyl, whereby C_1-2-alkyl may be unsubstituted or substituted with hydroxy, phenyl or sulfo, and

Q³ represents hydrogen, phenyl, C_1-2-alkylphenyl, C_1-4-alkyl, whereby C_1-4-alkyl may be unsubstituted or substituted with hydroxy, cyano, C_1-2-alkoxy or sulfo, and

Q⁴ represents hydrogen or hydroxy,

R⁵ represents hydrogen, C_1-4-alkyl, C_2-4-alkenyl, carboxy, NHCOC_1-4-alkyl, and

R⁶ and R⁷ each independently from each other represent hydrogen, halogen, sulfo, C_1-4-alkyl or carboxy, and

R⁸ represents hydrogen or C_1-4-alkyl,

R⁹ represents hydrogen, C_1-4-alkyl, and

R¹⁰ represents hydrogen or hydroxy,

R¹¹ and R¹² each independently from each other represent hydrogen, C_1-4-alkyl, C_1-4-alkoxy, hydroxy, halogen, amino, acetamido, sulfo, carboxy, C_1-4-alkoxycarbonyl or C_1-4-alkylaminocarbonyl, and

R² represents hydrogen, C_1-4-alkyl, C_1-4-alkoxy, halogen, carboxy or sulfo,

R³ and R⁴ each independently from each other represent hydrogen or C_1-4-alkyl,

R^1A represents a residue selected from the group consisting of

in whichn≧1,

A¹, A², R², R³ and R⁴ have the meaning as indicated for the preferred 4,4′-diazobenzanilide derivatives 1A, and X represents C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, NH or S.

In more preferred 4,4′-diazobenzanilide derivatives 1A

A¹ represents phenyl or 2-naphthyl, whereby phenyl and 2-naphthyl are substituted with at least one sulfo group, and whereby phenyl may additionally be mono-substituted with C_1-4-alkyl or C_1-4-alkoxy, and

A² represents a residue selected from the group consisting of

in which

Z¹ represents C_1-4-alkyl,

Z² represents phenyl, whereby phenyl may be unsubstituted or mono-, di- or trisubstituted with sulfo, C_1-4-alkyl or C_1-4-alkoxy,

Y represents O or N—CN,

Q¹ represents hydrogen or C_1-2-alkyl,

Q² represents cyano, C_1-2-alkyl or carbamoyl, whereby C_1-2-alkyl may be unsubstituted or substituted with sulfo,

Q³ represents C_1-4-alkyl,

Q⁴ represents hydroxy,

R⁵ represents hydrogen or C_1-4-alkyl, R⁶ and R⁷ each independently from each other represent hydrogen, sulfo or C_1-4-alkyl,

R⁹ represents hydrogen or C_1-4-alkyl,

R² represents hydrogen or C_1-4-alkyl,

R³ and R⁴ each independently from each other represent hydrogen or C_1-4-alkyl,

R^1A represents a residue selected from the group consisting of

in whichn≧1,and A¹, A², R², R³ and R⁴ have the meaning as indicated above for the more preferred 4,4′-diazobenzanilide derivatives 1A.

In even more preferred 4,4′-diazobenzanilide derivatives 1A

A¹ represents phenyl or 2-naphtyl, whereby phenyl is substituted with at least one sulfo group and 2-naphthyl is substituted with at least two sulfo groups, and

A² represents a residue selected from the group consisting of

in which

Z¹ represents C_1-4-alkyl,

Z² represents phenyl, whereby phenyl may be unsubstituted or mono-, di- or trisubstituted with sulfo, C_1-4-alkyl or C_1-4-alkoxy,

Y represents O or N—CN,

Q¹ represents hydrogen C_1-2-alkyl,

Q² represents cyano,

Q³ represents C_1-4-alkyl,

Q⁴ represents hydroxy,

R⁵ represents C_1-4-alkyl,

R⁶ and R⁷ represent hydrogen,

R² represents hydrogen or C_1-4-alkyl, and

R³ and R⁴ represent hydrogen, and

R^1A represents a residue selected from the group consisting of

in whichn≧1,m≧0,and A¹, A², R², R³ and R⁴ have the meaning as indicated above for the even more preferred 4,4′-diazobenzanilide derivatives 1A.

In most preferred 4,4′-diazobenzanilide derivatives 1A

A¹ represents 4-sulfophenyl, 6,8-disulfo 2-naphthyl or 4,8-disulfo 2-naphthyl, and

A² represents a residue selected from the group consisting of

in which

Z¹ represents methyl,

Z² represents 5-methyl-2-methoxy-4-sulfophenyl

Y represents O or N—CN,

Q¹ represents methyl,

Q² represents cyano,

Q³ represents ethyl,

Q⁴ represents hydroxy,

R⁵ represents methyl

R⁶ and R⁷ represent hydrogen,

R² represents hydrogen or methyl, and

R³ and R⁴ represent hydrogen, and

R^1A represents a residue selected from the group consisting of 2-hydroxyethyl and

in which

A¹, A², R², R³ and R⁴ have the meaning as indicated above for the most preferred 4,4′-diazobenzanilide derivatives 1A.

Also part of the invention is the 4-amino-4′-azobenzanilide derivative of the formula

in which A¹, R², R³ and R⁴ have the meaning as indicated above, and

R^1A represents a residue selected from the group consisting of

in whichn≧1,

A¹, R², R³ and R⁴ have the meaning as indicated above, and

X represents C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, NH or S.

The process of the present invention for the preparation of 4-amino-4′-azobenzanilide derivative of the formula

in which A¹, R², R³ and R⁴ have the meaning as indicated above, and

R^1B represents a residue selected from the group consisting of

in whichn≧1,comprises the steps of

• • i) reacting a 2-nitrophenol derivative of the formula

• •  with a compound of the formula

R^1B-LG  (4B)

• •  in which LG represents a leaving group, to yield a nitrobenzol derivative of the formula

• • ii) reducing the nitrobenzol derivative of formula 5B obtained in step i) to yield an aniline derivative of the formula

• • iii) diazotizing an amine of the formula

A¹-NH₂  (7)

• •  to yield a diazonium ion of the formula

A¹—N⁺≡N  (8)

• • iv) coupling the diazonium ion of the formula 8 obtained in step iii) with the aniline derivative of formula 6B obtained in step ii) to yield a coupling product of the formula

• • v) reacting the coupling product of formula 9B obtained in step iv) with a nitrobenzoylchloride derivative of the formula

• •  to yield a nitro compound of the formula

• • vi) reducing the nitro compound of the formula 11B obtained in step v) to yield the 4-amino-4′-azobenzanilide derivative of formula 2B.

Leaving group can be those functionalities typically used in the synthesis of alkylarylethers via Williamson synthesis, e.g. halogen, sulfate or arylsulfonate.

The process of the present invention for the preparation of 4-amino-4′-azobenzanilide derivative of the formula

in which A¹, R², R³ and R⁴ have the meaning as indicated above, and R^1C represents

in which

A¹, R², R³ and R⁴ have the meaning as indicated above, and

X represents C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, NH or S,

comprises the steps of

• • i) reacting a 2-nitrophenol derivative of the formula

• •  with a compound of the formula

• •  in which LG represents a leaving group, to yield a nitrobenzol derivative of the formula

• • ii) reducing the nitrobenzol derivative of formula 13 obtained in step i) to yield an aniline derivative of the formula

• • iii) diazotizing an amine of the formula

A¹-NH₂  (7)

• •  to yield a diazonium ion of the formula

A¹—N⁺≡N  (8)

• • iv) coupling the diazonium ion of the formula 8 obtained in step iii) with the aniline derivative of formula 14 obtained in step ii) to yield a coupling product of the formula

• • v) reacting the coupling product of formula 15 obtained in step iv) with a nitrobenzoylchloride derivative of the formula

• •  to yield a nitro compound of the formula

• • vi) reducing the nitro compound of the formula 16 obtained in step v) to yield the 4-amino-4′-azobenzanilide derivative of formula 2C.

The process of the present invention for the preparation of 4,4′-diazobenzanilide derivative of the formula

in which A¹, A², R², R³ and R⁴ have the meaning as indicated above and R^1A represents a residue selected from the group consisting of

in whichn≧1,

A¹, A², R², R³ and R⁴ have the meaning as indicated above, and

X represents C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, NH or S.

comprises the steps of

• • i) diazotizing a 4-amino-4′-azobenzanilide derivative of the formula

• •  to yield a diazonium ion of the formula

• •  in which A¹, R², R³ and R⁴ have the meaning as indicated above and R^1A represents a residue selected from the group consisting of

• • in which
  • n≧1,
  • A¹, A², R², R³ and R⁴ have the meaning as indicated above, and
  • X represents C_2-14-alkylene, whereby a —CH₂CH₂CH₂— unit of C_2-14-alkylene may be replaced by a —CH₂-E-CH₂— unit, in which E represents O, NH or S,
  • ii) coupling the diazonium ion 17A obtained in step i) with a compound of the formula

A²-H  (18)

• •  in which A² has the meaning as indicated above to yield the 4,4′-diazobenzanilide derivative 1A.

Preferably, the 4-amino-4′-azobenzanilide derivative is prepared according to one of the above processes of the present invention.

A₁-NH₂ and A²-H are known compounds or may be prepared by known methods.

The 4,4′-diazobenzanilide derivatives 1A can be used for dyeing natural or synthetic materials such as paper, cellulose, polyamide, leather or glass fibres. Preferably, the 4,4′-diazobenzanilide derivatives 1A are used for dyeing paper.

Paper dyed with the 4,4′-diazobenzanilide derivatives 1A is also part of the invention.

The 4,4′-diazobenzanilide derivatives 1A can be applied to the materials, preferably to paper, in the form of aqueous or solid formulations.

The aqueous and solid formulations comprising 4,4′-diazobenzanilide derivatives 1A are also part of the invention.

The solid formulations comprising 4,4′-diazobenzanilide derivatives 1A can be powders or granulate materials, and may include auxiliaries. Examples of auxiliaries are solubilizers such as urea, extenders such as dextrin, Glauber salt or sodium chloride, sequestrants such as tetrasodium phosphate, and also dispersants and dustproofing agents.

The aqueous formulations comprising 4,4′-diazobenzanilide derivatives 1A may also include auxiliaries. Examples of auxiliaries used for aqueous formulations are solubilizers such as ε-caprolactam or urea, and organic solvents such as glycols, polyethylene glycols, dimethyl sulphoxide, N-methylpyrrolidone, acetamide, alkanolamines or polyglycolamines.

Preferably, the aqueous formulations are aqueous solutions which comprise from 5 to 30% by weight 4,4′-diazobenzanilide derivatives 1A based on the weight of the solution. Preferably, these concentrated aqueous solutions also contain a low level of inorganic salts, which may be achieved by known methods, for example by reverse osmosis.

Aqueous formulations of the 4,4′-diazobenzanilide derivatives 1A can also be used for the preparation of inks.

The 4,4′-diazobenzanilide derivatives 1A are dyes of yellow or orange shade, which can be synthesized from ecological harmless starting materials, and which show a good brilliance, a high substantivity, a high degree of exhaustion and a good to very good lightfastness.

EXAMPLES

Example 1

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R², R³ and R⁴ are hydrogen and R^1A, respectively, R^1B is 2-hydroxyethyl)

Ethylene chlorohydrin (143.2 g) is added to a solution of 2-nitrophenol (139.11 g) in water (225 g) at 75 to 80° C. and at pH 8.8 to 9.3 within 30 minutes. The reaction mixture is stirred overnight, aqueous ammonia (25 w %, 34 g) is added and the reaction mixture is stirred for further 30 minutes. The organic layer containing the nitrobenzol derivative 5a (R^1B is 2-hydroxyethyl, R² is hydrogen) is separated, diluted with a mixture of ethanol/water (1/3.7, 1400 mL) and heated to 85 to 90° C. Sodium sulfide (141.8 g) is added and the reaction mixture is stirred until the reaction was complete. The reaction mixture is cooled to room temperature and concentrated. The obtained suspension is filtered and the filter cake is dried in vacuo to yield 135.5 g of the aniline derivative 6a (R^1B is 2-hydroxyethyl, R² is hydrogen).

Aqueous HCl (32 w %, 35 g) is added to a suspension of 2-naphthylamine-6,8-disulfonic acid (36.9 g) in water (300 mL) at 5 to 10° C., followed by addition of sodium nitrite (4 N, 32 mL) within 40 minutes. The reaction mixture is stirred for 1 hour, and then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension obtaining the diazonium ion 8a (A¹ is 6,8-disulfo-2-naphthyl) is obtained.

This suspension is added to a suspension of the aniline derivative 6a (18.9 g) in water (300-mL) at pH 4.5 to 5.0 within 30 minutes. The reaction mixture is stirred at pH 4.5 to 5.0 until the reaction is complete. The reaction mixture is concentrated and treated with sodium chloride. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 53.7 g of the coupling product 9a (A¹ is 6,8-disulfo-2-naphthyl, R^1B is 2-hydroxyethyl, R² is hydrogen).

A solution of 4-nitrobenzoylchloride (5.7 g) in acetone (50 mL) is added to a suspension of the coupling product 9a (13 g) in water (150 g) at below 32° C. and at pH 6.5 to 7.0. The reaction mixture is stirred overnight, filtered and the filter cake is dried in vacuo to yield 13.7 g of the nitro compound 11a (A¹ is 6,8-disulfo-2-naphthyl, R^1B is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen).

Aqueous sodium sulfide (60 w %, 4.8 g) is added to a suspension of the nitro compound 11a (13 g) in water (80 g) at 50° C. The reaction mixture is stirred at 50 to 55° C. for 1 hour, treated with sodium chloride and concentrated. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 8.9 g of the 4-amino-4′-azobenzanilide derivative of the formula 2a.

Examples 2 to 60

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(2A, respectively, 2B)

in which R³ and R⁴ are hydrogen, and

TABLE 1
Example No/
Compound No	A1	R1A, respectively, R1B	R2
2/2b	6,8-disulfo-2-naphthyl		hydrogen
3/2c	6,8-disulfo-2-naphthyl		hydrogen
4/2d	6,8-disulfo-2-naphthyl		hydrogen
5/2e	6,8-disulfo-2-naphthyl		hydrogen
6/2f	6,8-disulfo-2-naphthyl		methyl
7/2g	6,8-disulfo-2-naphthyl		methyl
8/2h	6,8-disulfo-2-naphthyl		methyl
9/2i	6,8-disulfo-2-naphthyl		methyl
10/2j	6,8-disulfo-2-naphthyl		methyl
11/2k	4,8-disulfo-2-naphthyl		hydrogen
12/2l	4,8-disulfo-2-naphthyl		hydrogen
13/2m	4,8-disulfo-2-naphthyl		hydrogen
14/2n	4,8-disulfo-2-naphthyl		hydrogen
15/2o	4,8-disulfo-2-naphthyl		hydrogen
16/2p	4,8-disulfo-2-naphthyl		methyl
17/2q	4,8-disulfo-2-naphthyl		methyl
18/2r	4,8-disulfo-2-naphthyl		methyl
19/2s	4,8-disulfo-2-naphthyl		methyl
20/2t	4,8-disulfo-2-naphthyl		methyl
21/2u	3,6-disulfo-2-naphthyl		hydrogen
22/2v	3,6-disulfo-2-naphthyl		hydrogen
23/2w	3,6-disulfo-2-naphthyl		hydrogen
24/2x	3,6-disulfo-2-naphthyl		hydrogen
25/2y	3,6-disulfo-2-naphthyl		hydrogen
26/2z	3,6-disulfo-2-naphthyl		methyl
27/2aa	3,6-disulfo-2-naphthyl		methyl
28/2ab	3,6-disulfo-2-naphthyl		methyl
29/2ac	3,6-disulfo-2-naphthyl		methyl
30/2ad	3,6-disulfo-2-naphthyl		methyl
31/2ae	5,7-disulfo-2-naphthyl		hydrogen
32/2af	5,7-disulfo-2-naphthyl		hydrogen
33/2ag	5,7-disulfo-2-naphthyl		hydrogen
34/2ah	5,7-disulfo-2-naphthyl		hydrogen
35/2ai	5,7-disulfo-2-naphthyl		hydrogen
36/2aj	5,7-disulfo-2-naphthyl		methyl
37/2ak	5,7-disulfo-2-naphthyl		methyl
38/2al	5,7-disulfo-2-naphthyl		methyl
39/2am	5,7-disulfo-2-naphthyl		methyl
40/2an	5,7-disulfo-2-naphthyl		methyl
41/2ao	1,5-disulfo-2-naphthyl		hydrogen
42/2ap	1,5-disulfo-2-naphthyl		hydrogen
43/2aq	1,5-disulfo-2-naphthyl		hydrogen
44/2ar	1,5-disulfo-2-naphthyl		hydrogen
45/2as	1,5-disulfo-2-naphthyl		hydrogen
46/2at	1,5-disulfo-2-naphthyl		methyl
47/2au	1,5-disulfo-2-naphthyl		methyl
48/2av	1,5-disulfo-2-naphthyl		methyl
49/2aw	1,5-disulfo-2-naphthyl		methyl
50/2ax	1,5-disulfo-2-naphthyl		methyl
51/2ay	1,6-disulfo-2-naphthyl		hydrogen
52/2az	1,6-disulfo-2-naphthyl		hydrogen
53/2ba	1,6-disulfo-2-naphthyl		hydrogen
54/2bb	1,6-disulfo-2-naphthyl		hydrogen
55/2bc	1,6-disulfo-2-naphthyl		hydrogen
56/2bd	1,6-disulfo-2-naphthyl		methyl
57/2be	1,6-disulfo-2-naphthyl		methyl
58/2bf	1,6-disulfo-2-naphthyl		methyl
59/2bg	1,6-disulfo-2-naphthyl		methyl
60/2bh	1,6-disulfo-2-naphthyl		methyl

These 4-amino-4′-azobenzanilide derivative are prepared in analogy to example 1.

Example 61

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(A¹ is 6-sulfo-2-naphthyl, R² is methyl, R³ and R⁴ are hydrogen and R^1A, respectively, R^1B, is 2-hydroxyethyl)

Ethylene chlorohydrin (120.8 g) is added to a solution of 4-methyl-2-nitrophenol (153.1 g) in water (225 g) at 75 to 80° C. and at pH 8.8 to 9.3 within 5 minutes. The reaction mixture is stirred overnight, aqueous ammonia (25 w %, 34 g) is added and the reaction mixture is stirred for further 30 minutes. The organic layer containing the nitrobenzol derivative 5b (R^1B is 2-hydroxyethyl, R² is methyl) is separated, diluted with isopropanol (22 mL) and heated to 85 to 90° C. Sodium sulfide (132.6 g) in 220 g of water is added slowly and the reaction mixture is stirred until the reaction was complete. The reaction mixture is cooled to room temperature. The obtained suspension is filtered and the filter cake is dried in vacuo to yield 137 g of the aniline derivative 6b (R^1B is 2-hydroxyethyl, R² is methyl).

Aqueous HCl (32 w %, 28.5 g) is added to a suspension of 2-naphthylamine-6-sulfonic acid (22.3 g) in water (300 mL) at 5 to 10° C., followed by addition of sodium nitrite (4 N, 25.5 mL) within 40 minutes. The reaction mixture is stirred for 1 hour, and then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension obtaining the diazonium ion 8b (A¹ is 6-sulfo-2-naphthyl) is obtained.

This suspension is added to a suspension of the aniline derivative 6b (R^1B is 2-hydroxyethyl, R² is methyl) (17 g) in water (100 mL) at pH 3.0 to 3.8 within 30 minutes. The reaction mixture is stirred at pH 3.0 to 3.8 until the reaction is complete, stirred overnight, filtered and the filter cake is dried in vacuo to yield 40 g of the coupling product 9b (A¹ is 6-sulfo-2-naphthyl, R^1B is 2-hydroxyethyl, R² is methyl).

A solution of 4-nitrobenzoylchloride (12.15 g) in acetone (75 mL) is added to a suspension of the coupling product 9b (25 g) in water (150 g) at below 32° C. and at pH 6.5 to 7.0. The reaction mixture is stirred overnight, filtered and the filter cake is dried in vacuo to yield 31.3 g of the nitro compound 11b (A¹ is 6-sulfo-2-naphthyl, R^1B is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen).

Aqueous sodium sulfide (60 w %, 4.8 g) is added to a suspension of the nitro compound 11b (10 g) in water (80 g) at 50° C. The reaction mixture is stirred at 50 to 55° C. for 1 hour, filtered and the filter cake is dried in vacuo to yield 8.6 g of the 4-amino-4′-azobenzanilide derivative of the formula 2bi.

Example 62

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(A¹ is 4-sulfophenyl, R², R³ and R⁴ are hydrogen and R^1A, respectively, R^1B is 2-hydroxyethyl).

Ethylene chlorohydrin (143.2 g) is added to a solution of 2-nitrophenol (139.11 g) in water (225 g) at 75 to 80° C. and at pH 8.8 to 9.3 within 30 minutes. The reaction mixture is stirred overnight, aqueous ammonia (25 w %, 34 g) is added and the reaction mixture is stirred for further 30 minutes. The organic layer containing the nitrobenzol derivative 5a (R^1B is 2-hydroxyethyl, R² is hydrogen) is separated, diluted with a mixture of ethanol/water (1/3.7, 1400 mL) and heated to 85 to 90° C. Sodium sulfide (141.8 g) is added and the reaction mixture is stirred until the reaction is complete. The reaction mixture is cooled to room temperature and concentrated. The obtained suspension is filtered and the filter cake is dried in vacuo to yield 135.5 g of the aniline derivative 6a (R^1B is 2-hydroxyethyl, R² is hydrogen).

Aqueous HCl (32 w %, 42.7 g) is added to a suspension of aniline-4-sulfonic acid (26 g) in water (200 mL) at 5 to 10° C., followed by addition of sodium nitrite (4 N, 38 mL) within 40 minutes. The reaction mixture is stirred for 1 hour, and then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 8c (A¹ is 4-sulfophenyl) is obtained.

This suspension is added to a suspension of the aniline derivative 6a (24.2 g) in water (300 mL) at pH 2.0 to 2.5 within 30 minutes. The reaction mixture is stirred at pH 2.0 to 2.5 until the reaction was complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 35.4 g of the coupling product 9c (A¹ is 4-sulfophenyl, R^1B is 2-hydroxyethyl, R² is hydrogen).

A solution of 4-nitrobenzoylchloride (6 g) in acetone (30 mL) is added to a suspension of the coupling product 9c (10 g) in water (150 g) at below 32° C. and at pH 6.5 to 7.0. The reaction mixture is stirred overnight, filtered and the filter cake is dried in vacuo to yield 11.1 g of the nitro compound 11c (A¹ is 4-sulfophenyl, R^1B is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen).

Aqueous sodium sulfide (60 w %, 4.7 g) is added to a suspension of the nitro compound 11c (10 g) in water (100 g) at 50° C. The reaction mixture is stirred at 50 to 55° C. for 1 hour, then treated with sodium chloride. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 9 g of the 4-amino-4′-azobenzanilide derivative of the formula 2bj.

Examples 63 to 122

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(2A, respectively, 2B)

in which R³ and R⁴ are hydrogen, and

TABLE 2
Example No/
Compound No	A1	R1A, respectively, R1B	R2
63/2bk	4-sulfophenyl		hydrogen
64/2b1	4-sulfophenyl		hydrogen
65/2bm	4-sulfophenyl		hydrogen
66/2bn	4-sulfophenyl		hydrogen
67/2bo	4-sulfophenyl		hydrogen
68/2bp	4-sulfophenyl		methyl
69/2bq	4-sulfophenyl		methyl
70/2br	4-sulfophenyl		methyl
71/2bs	4-sulfophenyl		methyl
72/2bt	4-sulfophenyl		methyl
73/2bu	3-sulfophenyl		hydrogen
74/2bv	3-sulfophenyl		hydrogen
75/2bw	3-sulfophenyl		hydrogen
76/2bx	3-sulfophenyl		hydrogen
77/2by	3-sulfophenyl		hydrogen
78/2bz	3-sulfophenyl		methyl
79/2ca	3-sulfophenyl		methyl
80/2cb	3-sulfophenyl		methyl
81/2cc	3-sulfophenyl		methyl
82/2cd	3-sulfophenyl		methyl
83/2ce	4-sulfo-o-tolyl		hydrogen
84/2cf	4-sulfo-o-tolyl		hydrogen
85/2cg	4-sulfo-o-tolyl		hydrogen
86/2ch	4-sulfo-o-tolyl		hydrogen
87/2ci	4-sulfo-o-tolyl		hydrogen
88/2cj	4-sulfo-o-tolyl		methyl
89/2ck	4-sulfo-o-tolyl		methyl
90/2cl	4-sulfo-o-tolyl		methyl
91/2cm	4-sulfo-o-tolyl		methyl
92/2cn	4-sulfo-o-tolyl		methyl
93/2co	2,5-disulfophenyl		hydrogen
94/2cp	2,5-disulfophenyl		hydrogen
95/2cq	2,5-disulfophenyl		hydrogen
96/2cr	2,5-disulfophenyl		hydrogen
97/2cs	2,5-disulfophenyl		hydrogen
98/2ct	2,5-disulfophenyl		methyl
99/2cu	2,5-disulfophenyl		methyl
100/2cv	2,5-disulfophenyl		methyl
101/2cw	2,5-disulfophenyl		methyl
102/2cx	2,5-disulfophenyl		methyl
103/2cy	3-sulfo-p-tolyl		hydrogen
104/2cz	3-sulfo-p-tolyl		hydrogen
105/2da	3-sulfo-p-tolyl		hydrogen
106/2db	3-sulfo-p-tolyl		hydrogen
107/2dc	3-sulfo-p-tolyl		hydrogen
108/2dd	3-sulfo-p-tolyl		methyl
109/2de	3-sulfo-p-tolyl		methyl
110/2df	3-sulfo-p-tolyl		methyl
111/2dg	3-sulfo-p-tolyl		methyl
112/2dh	3-sulfo-p-tolyl		methyl
113/2di	2-methoxy-5-sulfo-phenyl		hydrogen
114/2dj	2-methoxy-5-sulfo-phenyl		hydrogen
115/2dk	2-methoxy-5-sulfo-phenyl		hydrogen
116/2dl	2-methoxy-5-sulfo-phenyl		hydrogen
117/2dm	2-methoxy-5-sulfo-phenyl		hydrogen
118/2dn	2-methoxy-5-sulfo-phenyl		methyl
119/2do	2-methoxy-5-sulfo-phenyl		methyl
120/2dp	2-methoxy-5-sulfo-phenyl		methyl
121/2dq	2-methoxy-5-sulfo-phenyl		methyl
122/2dr	2-methoxy-5-sulfo-phenyl		methyl

These 4-amino-4′-azobenzanilide derivatives are prepared in analogy to example 62.

Example 123

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R² is methyl, R³ and R⁴ are hydrogen and R^1A, respectively, R^1C is

1,2-Bis(2-chloroethoxy)ethane (56.1 g) is added to a solution of 4-methyl-2-nitrophenol (91.8 g), potassium carbonate (91.2 g) and potassium iodide (12.4 g) in dimethylformamide (500 mL) at 70° C. within 40 minutes. The reaction mixture is stirred at 100° C. for 3 hours. Then it is cooled to 40° C. and filtered. The filtrate is concentrated in vacuo. The remaining oil is diluted with tert-butyl methyl ether and cooled to room temperature. A precipitate is obtained which is separated by filtration and dried to yield 92.2 g of the nitrobenzol derivative 13a (R² is methyl, X is CH₂CH₂OCH₂CH₂OCH₂CH₂).

Aqueous sodium sulfide (60 w %, 52 g) is added to a solution of the nitrobenzol derivative 13a (84.1 g) in dimethylformamide (250 mL) at 80° C. and the reaction mixture is stirred at 100° C. for 1 hour. The reaction mixture is cooled to room temperature and concentrated. The obtained suspension is filtered and the filter cake is dried in vacuo to yield 70.5 g of the aniline derivative 14a (R² is methyl, X is CH₂CH₂OCH₂CH₂OCH₂CH₂).

Aqueous HCl (32 w %, 18.8 g) is added to a suspension of 2-naphthylamine-6,8-disulfonic acid (20 g) in water (200 mL) at 5 to 10° C., followed by addition of sodium nitrite (4 N, 17 mL) within 40 minutes. The reaction mixture is stirred for 1 hour, and then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 8a (A¹ is 6,8-disulfonaphthyl) is obtained.

This suspension is added to a suspension of the aniline derivative 14a (11.9 g) in water (150 mL) at pH 2.0 to 2.5 within 30 minutes. The reaction mixture is stirred at pH 2.0 to 4.0 until the reaction is complete. The reaction mixture is treated with sodium chloride, the resulting suspension is filtered and the filter cake is dried in vacuo to yield 24.5 g of the coupling product 15a (A¹ is 6,8-disulfonaphthyl, R² is methyl, X is CH₂CH₂OCH₂CH₂—OCH₂CH₂).

A solution of 4-nitrobenzoylchloride (9.7 g) in acetone (30 mL) is added to a suspension of the coupling product 15a (11.8 g) in water (100 g) at below 32° C. and at pH 6.5 to 7.0. The reaction mixture is stirred overnight, filtered and the filter cake is dried in vacuo to yield 10.8 g of the nitro compound 16a (A¹ is 6,8-disulfonaphthyl, R² is methyl, X is CH₂CH₂OCH₂CH₂OCH₂CH₂, R³ and R⁴ are hydrogen).

Aqueous sodium sulfide (60 w %, 4.9 g) is added to a suspension of the nitro compound 16a (10 g) in brine (20 w %, 100 g) at 50° C. The reaction mixture is stirred at 50 to 55° C. for 1 hour, cooled to room temperature and treated with sodium chloride. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 6.4 g of the 4-amino-4′-azobenzanilide derivative of the formula 2ds.

Examples 124 to 146

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(2A, respectively, 2C)

in which R^1A, respectively, R^1C is

X is CH₂CH₂OCH₂CH₂OCH₂CH₂, R³ and R⁴ are hydrogen, and

	TABLE 3
	Example No/
	Compound No	A1	R2
	124/2dt	6,8-disulfo-2-naphthyl	hydrogen
	125/2du	4,8-disulfo-2-naphthyl	methyl
	126/2dv	4,8-disulfo-2-naphthyl	hydrogen
	127/2dw	3,6-disulfo-2-naphthyl	methyl
	128/2dx	3,6-disulfo-2-naphthyl	hydrogen
	129/2dy	5,7-disulfo-2-naphthyl	methyl
	130/2dz	5,7-disulfo-2-naphthyl	hydrogen
	131/2ea	1,5-disulfo-2-naphthyl	methyl
	132/2eb	1,5-disulfo-2-naphthyl	hydrogen
	133/2ec	1,6-disulfo-2-naphthyl	methyl
	134/2ed	1,6-disulfo-2-naphthyl	hydrogen
	135/2ee	4-sulfophenyl	hydrogen
	136/2ef	4-sulfophenyl	methyl
	137/2eg	3-sulfophenyl	hydrogen
	138/2eh	3-sulfophenyl	methyl
	139/2ei	4-sulfo-o-tolyl	hydrogen
	140/2ej	4-sulfo-o-tolyl	methyl
	141/2ek	2,5-disulfophenyl	hydrogen
	142/2el	2,5-disulfophenyl	methyl
	143/2em	3-sulfo-p-tolyl	hydrogen
	144/2en	3-sulfo-p-tolyl	methyl
	145/2eo	2-methoxy-5-sulfo-	hydrogen
		phenyl
	146/2ep	2-methoxy-5-sulfo-	methyl
		phenyl

These 4-amino-4′-azobenzanilide derivatives are prepared in analogy to example 123.

Examples 147 to 170

Preparation of the 4-amino-4′-azobenzanilide derivative of the formula

(2A, respectively, 2C)

in which R^1A respectively, R^1C is

X is CH₂CH₂CH₂CH₂CH₂CH₂, R³ and R⁴ are hydrogen, and

	TABLE 4
	Example No/
	Compound No	A1	R2
	147/2eq	6,8-disulfo-2-naphthyl	methyl
	148/2er	6,8-disulfo-2-naphthyl	hydrogen
	149/2es	4,8-disulfo-2-naphthyl	methyl
	150/2et	4,8-disulfo-2-naphthyl	hydrogen
	151/2eu	3,6-disulfo-2-naphthyl	methyl
	152/2ev	3,6-disulfo-2-naphthyl	hydrogen
	153/2ew	5,7-disulfo-2-naphthyl	methyl
	154/2ex	5,7-disulfo-2-naphthyl	hydrogen
	155/2ey	1,5-disulfo-2-naphthyl	methyl
	156/2ez	1,5-disulfo-2-naphthyl	hydrogen
	157/2fa	1,6-disulfo-2-naphthyl	methyl
	158/2fb	1,6-disulfo-2-naphthyl	hydrogen
	159/2fc	4-sulfophenyl	hydrogen
	160/2fd	4-sulfophenyl	methyl
	161/2fe	3-sulfophenyl	hydrogen
	162/2ff	3-sulfophenyl	methyl
	163/2fg	4-sulfo-o-tolyl	hydrogen
	164/2fh	4-sulfo-o-tolyl	methyl
	165/2fi	2,5-disulfophenyl	hydrogen
	166/2fj	2,5-disulfophenyl	methyl
	167/2fk	3-sulfo-p-tolyl	hydrogen
	168/2fl	3-sulfo-p-tolyl	methyl
	169/2fm	2-methoxy-5-sulfo-	hydrogen
		phenyl
	170/2fn	2-methoxy-5-sulfo-	methyl
		phenyl

These 4-amino-4′-azobenzanilide derivatives are prepared in analogy to example 123.

Example 171

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen, A² is

Aqueous sodium nitrite (4 N, 3 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2a (7 g), which is prepared as described in example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 4 g) in brine (25 w %, 70 g) at 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17a (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen) is obtained.

Barbituric acid (1.55 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 3.5 to 4.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield the 5.5 g of the 4,4′-diazobenzanilide derivative 1a.

Example 172

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen, A² is

Aqueous sodium nitrite (4 N, 3 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2a (7 g), which is prepared as described in example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 3.5 g) in brine (25 w %, 70 g) at 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17a (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen) is obtained.

Cyanoiminobarbituric acid (1.85 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 3.5 to 4.0, and stirred until the reaction was complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield the 7.2 g of the 4,4′-diazobenzanilide derivative 1b.

Example 173

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen, A² is

Aqueous sodium nitrite (4 N, 3 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2a (7 g), which is prepared as described in example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 3.5 g) in brine (25 w %, 70 g) at 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17a (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen) is obtained.

2-Methoxy-5-methyl-4-sulfoacetoacetanilide, sodium salt (3.9 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 3.5 to 4.0, and stirred until the reaction was complete. The resulting suspension was filtered and the filter cake was dried in vacuo to yield the 8.3 g of the 4,4′-diazobenzanilide derivative 1c.

Example 174

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen, A² is

Sodium chloride (20 g) and HCl (32 w %, 3.5 g) are added to a suspension of the 4-amino-4′ azobenzanilide derivative 2f (7 g), which is prepared in analogy to example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and aqueous sodium nitrite (4 N, 3 mL) are added at 0 to 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17b (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen) is obtained.

Cyanoiminobarbituric acid (1.81 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 3.5 to 4.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield the 8.9 g of the 4,4′-diazobenzanilide derivative 1d.

Example 175

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen, A² is

Sodium chloride (20 g) and HCl (32 w %, 3.5 g) are added to a suspension of the 4-amino-4′-azobenzanilide derivative 2f (7 g), which is prepared in analogy to example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and aqueous sodium nitrite (4 N, 3 mL) is added at 0 to 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17b (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen) is obtained.

Barbituric acid (1.53 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 3.5 to 4.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield the 6.5 g of the 4,4′-diazobenzanilide derivative 1e.

Example 176

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen, A² is

Sodium chloride (20 g) and HCl (32 w %, 3.5 g) are added to a suspension of the 4-amino-4′-azobenzanilide derivative 2f (7 g), which is prepared in analogy to example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and aqueous sodium nitrite (4 N, 3 mL) is added at 0 to 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17b (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen) is obtained.

2-Methoxy-5-methyl-4-sulfoacetoacetanilide, sodium salt (3.84 g) is added to this suspension. The pH of the reaction mixture is adjusted to 6.5. The reaction mixture is warmed to room temperature at pH 6.5 to 7.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 10 g of the 4,4′-diazobenzanilide derivative 1f.

Example 177

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen, A² is

Sodium chloride (15 g) and HCl (32 w %, 2 g) are added to a suspension of the 4-amino-4′-azobenzanilide derivative 2f (3.6 g), which is prepared in analogy to example 1, in water (75 g). The obtained suspension is cooled to 0 to 5° C. and aqueous sodium nitrite (4 N, 1.5 mL) is added at 0 to 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17b (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen) is obtained.

3-Methyl-1-phenyl-2-pyrazolin-5-one (1.07 g) is added to this suspension. The pH of the reaction mixture is adjusted to 5.0. The reaction mixture is warmed to room temperature at pH 5.0 to 5.5, and stirred until the reaction was complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 4.5 g of the 4,4′-diazobenzanilide derivative 1 g.

Example 178

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen, A² is

Sodium chloride (20 g) and HCl (32 w %, 2.5 g) are added to a suspension of the 4-amino-4′-azobenzanilide derivative 2f (4.5 g), which is prepared in analogy to example 1, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and aqueous sodium nitrite (4 N, 2 mL) is added at 0 to 5° C. within 40 minutes. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17b (A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R² is methyl, R³ and R⁴ are hydrogen) is obtained.

3-Cyano-1-ethyl-6-hydroxy-4-methyl-2-pyridone (1.35 g) is added to this suspension. The pH of the reaction mixture is adjusted to 3.0. The reaction mixture is warmed to room temperature at pH 3.0 to 3.5, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 5.2 g of the 4,4′-diazobenzanilide derivative 1 h.

Examples 179 to 196

Preparation of a 4,4′-diazobenzanilide derivative of the formula

in which A¹ is 6,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R³ and R⁴ are hydrogen, and

TABLE 5
Example No/
Compound No	A2	R2
179/1i		hydrogen
180/1j		hydrogen
181/1k		methyl
182/1l		hydrogen
183/1m		methyl
184/1n		hydrogen
185/1o		methyl
186/1p		hydrogen
187/1q		methyl
188/1r		hydrogen
189/1s		methyl
190/1t		hydrogen
191/1u		hydrogen
192/1v		methyl
193/1w		hydrogen
194/1x		methyl
195/1y		hydrogen
196/1z		methyl

These 4,4′-diazobenzanilide derivatives are prepared in analogy to example 171.

Example 197 to 200

Preparation of a 4,4′-diazobenzanilide derivative of the formula

in which A¹ is 4,8-disulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R³ and R⁴ are hydrogen, and

TABLE 6
Example No/
Compound No	A2	R2
197/1aa		hydrogen
198/1ab		hydrogen
199/1ac		hydrogen
200/1ad		hydrogen
200/1ae		hydrogen

These 4,4′-diazobenzanilide derivatives are prepared in analogy to example 171 starting from 4-amino-4′-azobenzanilide derivative 2k (example 11).

Examples 201 to 203

Preparation of a 4,4′-diazobenzanilide derivative of the formula

in which A¹ is 6-sulfo-2-naphthyl, R^1A is 2-hydroxyethyl, R³ and R⁴ are hydrogen, and

TABLE 7
Example No/
Compound No	A2	R2
201/1af		methyl
202/1ag		methyl
203/1ah		methyl

These 4,4′-diazobenzanilide derivatives are prepared in analogy to example 171 starting from 4-amino-4′-azobenzanilide derivative 1bi (example 61).

Example 204

Preparation the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R² is hydrogen, R³ and R⁴ are hydrogen, A² is

Aqueous sodium nitrite (4 N, 3 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2bj (6 g), which is prepared as described in example 62, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 4.5 g) and sodium chloride (25 g) in water (50 g) at 5° C. within 1 hour. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17c (A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen) is obtained.

Barbituric acid (1.72 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 4.0 to 4.5, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 7.5 g of the 4,4′-diazobenzanilide derivative 1ai.

Example 205

Preparation the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R² is hydrogen, R³ and R⁴ are hydrogen, A² is

Aqueous sodium nitrite (4 N, 3 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2bj (6 g), which is prepared as described in example 62, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 4.5 g) and sodium chloride (25 g) in water (50 g) at 5° C. within 1 hour. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17c (A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen) is obtained.

Cyanoiminobarbituric acid (2.04 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 4.0 to 4.5, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 4.9 g of the 4,4′-diazobenzanilide derivative 1aj.

Example 206

Preparation the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R² is hydrogen, R³ and R⁴ are hydrogen, A² is

Aqueous sodium nitrite (4 N, 3 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2bj (6 g), which is prepared as described in example 62, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 4.5 g) and sodium chloride (25 g) in water (50 g) at 5° C. within 1 hour. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17c (A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R², R³ and R⁴ are hydrogen) is obtained.

2-Methoxy-5-methyl-4-sulfoacetoacetanilide, sodium salt (4.33 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 6.5 to 7.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 8.4 g of the 4,4′-diazobenzanilide derivative 1ak.

Examples 207 to 229

Preparation of a 4,4′-diazobenzanilide derivative of the formula

in which A¹ is 4-sulfophenyl, R^1A is 2-hydroxyethyl, R³ and R⁴ are hydrogen, and

TABLE 8
Example No/
Compound No	A2	R2
207/1al		methyl
208/1am		methyl
209/1an		hydrogen
210/1ao		methyl
211/1ap		hydrogen
212/1aq		methyl
213/1ar		hydrogen
214/1as		methyl
215/1at		hydrogen
216/1au		methyl
217/1av		methyl
218/1aw		hydrogen
219/1ax		methyl
220/1ay		hydrogen
221/1az		methyl
222/1ba		hydrogen
223/1bb		methyl
224/1bc		hydrogen
225/1bd		methyl
226/1be		hydrogen
227/1bf		methyl
228/1bg		hydrogen
229/1bh		methyl

These 4,4′-diazobenzanilide derivatives are prepared in analogy to example 204.

Example 230

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R² is methyl, R³ and R⁴ are hydrogen, R^1A is

A² is

Aqueous sodium nitrite (4 N, 2.1 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2ds (5 g), which is prepared as described in example 123, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 2.8 g) and sodium chloride (20 g) in water (50 g) at 5° C. within 1 hour. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension obtaining the diazonium ion 17d (A¹ is 6,8-disulfo-2-naphthyl, R² is methyl, R³ and R⁴ are hydrogen, and R^1A is

is obtained.

2-Methoxy-5-methyl-4-sulfoacetoacetanilide, sodium salt (2.71 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 6.5 to 7.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 4.5 g of the 4,4′-diazobenzanilide derivative 1bi.

Example 231

Preparation of the 4,4′-diazobenzanilide derivative of the formula

(A¹ is 6,8-disulfo-2-naphthyl, R² is methyl, R³ and R⁴ are hydrogen, R^1A is

A² is

Aqueous sodium nitrite (4 N, 1.7 mL) is added to a suspension of the 4-amino-4′-azobenzanilide derivative 2ds (4 g), which is prepared as described in example 123, in water (100 g). The obtained suspension is cooled to 0 to 5° C. and added to a solution of HCl (32 w %, 2.0 g) and sodium chloride (20 g) in water (50 g) at 5° C. within 1 hour. The reaction mixture is stirred for 1 h. Then unreacted nitrite is destroyed by addition of sulfamic acid. A suspension containing the diazonium ion 17d (A¹ is 6,8-disulfo-2-naphthyl, R² is methyl, R³ and R⁴ are hydrogen, and R^1A is

is obtained.

Cyanoiminobarbituric acid (1.01 g) is added to this suspension. The pH of the reaction mixture is adjusted to 4.0. The reaction mixture is warmed to room temperature at pH 4.5 to 5.0, and stirred until the reaction is complete. The resulting suspension is filtered and the filter cake is dried in vacuo to yield 2.9 g of the 4,4′-diazobenzanilide derivative 1bj.

Examples 232 to 255

Preparation of a 4,4′-diazobenzanilide derivative of the formula

in which A¹ is 6,8-disulfo-2-naphthyl, R³ and R⁴ are hydrogen, and R^1A is

TABLE 9
and
Example No/Compound No	A2	R2
232/1bk		hydrogen
233/1bl		hydrogen
234/1bm		hydrogen
235/1bn		methyl
236/1bo		hydrogen
237/1bp		methyl
238/1bq		hydrogen
239/1br		methyl
240/1bs		hydrogen
241/1bt		methyl
242/1bu		hydrogen
243/1bv		methyl
244/1bw		hydrogen
245/1bx		methyl
246/1by		hydrogen
247/1bz		methyl
248/1ca		hydrogen
249/1cb		methyl
250/1cc		hydrogen
251/1cd		methyl
252/1ce		hydrogen
253/1cf		methyl
254/1cg		hydrogen
255/1ch		methyl

These 4,4′-diazobenzanilide derivatives are prepared in analogy to example 231.

Examples 256 to 281

Preparation of a 4,4′-diazobenzanilide derivative of the formula

in which A¹ is 4-sulfophenyl, R³ and R⁴ are hydrogen, and R^1A is

TABLE 10
and
Example No/Compound No	A2	R2
256/1ci		hydrogen
257/1cj		methyl
258/1ck		hydrogen
259/1cl		methyl
260/1cm		hydrogen
261/1cn		methyl
262/1co		hydrogen
263/1cp		methyl
264/1cq		hydrogen
265/1cr		methyl
266/1cs		hydrogen
267/1ct		methyl
268/1cu		hydrogen
269/1cv		methyl
270/1cw		hydrogen
271/1cx		methyl
272/1cy		hydrogen
273/1cz		methyl
274/1da		hydrogen
275/1db		methyl
276/1dc		hydrogen
277/1dd		methyl
278/1de		hydrogen
279/1df		methyl
280/1dg		hydrogen
281/1dh		methyl

These 4,4′-diazobenzanilide derivatives are prepared in analogy to example 231.

Application Examples

A fiber mixture of a suspension of 50% by weight sulfite long fiber bleached (spruce) and a suspension of 50% by weight sulfite short fiber bleached (beech) is suspended in deionised water, as a 2% suspension, refined and beaten to a degree of 22°SR (Schopper Riegler). After dewatering by means of a centrifuge and testing for dry weight, the equivalent to 10 g dry fiber is placed in a beaker and diluted with tab water to a final volume of 500 mL. After stirring for 1 hour, an amount of the respective 4,4′-diazobenzanilide derivative sufficient to produce a dyeing of 0.2 reference depth based on the weight of dry fibre, as a 5 g/L aqueous solution, is added to the furnish suspension and stirring is continued for further 15 minutes. The suspension is made up to 700 mL with tab water and from 300 mL of the resulting suspension a hand sheet is produced using a Lhomargy sheet former. After drying on a cylinder at 90° C. for 12 minutes, the CIELab coordinates and degrees of exhaustion of the dyes in the dyeings obtained are measured. The CIELab coordinates are used to calculate the shade of the dye (characterized by the °Hue value) and the brilliance of the dyeing (characterized by the C* value). The backwater ratings of the effluents are also assessed on a scale of from 1 to 5. The lighfastness is determined according to ISO/105/B02 using a xenon lamp and blue wool references corresponding to a scale from 1 to 8.

The results are summarized in Table 11 below.

TABLE 11
	Amount Dye
4,4′-diazo-	[% dry				Degree of
benzanilide	weight/dry			Back-	Exhaustion	Light-
derivative	weight fiber]	°Hue	C*	water	[%]	fastness
1a	0.31	90.9	60.7	4+	93-95	4
1b	0.3	90.0	63.4	3-4+	93-95	4
1c	0.47	91.4	57.3	4+	94-96	4
1d	0.32	84.5	62.7	4-5	98	4
1e	0.29	85.5	61.2	4-5+	98-99	4
1f	0.35	86.9	58.2	4-5	98	4
1g	0.3	82.3	61.8	4-5	98	3-4
1h	0.44	72.6	58.5	3-4	92-94	2-3
1aa	0.45	87.0	58.9	4	94-96	4
1ab	0.44	88.2	63.9	4-5	97	4
1ac	0.3	90.4	65.0	4	93-95	4
1ad	0.38	91.8	62.0	4+	94-95	4+
1ae	0.45	92.7	58.0	4	93-95	4
1af	0.42	83.8	59.3	3-4+	92-94	4
1ag	0.36	84.4	62.7	4	95-97	4
1ah	0.40	87.5	59.3	4-5	97-99	4
1ai	0.36	93.6	57.9	4+	91-93	3-4
1aj	0.26	91.4	63.8	4+	94-96	3-4
1ak	0.4	91.2	51.5	4+	93-95	3+
1ap	20.0	83.7	51.2	2	~55	3
1ar	18.0	86.4	60.5	4-5	98	2-3+
1at	0.42	86.3	58.1	3-4	90-92	3+
1bi	0.48	85.6	58.5	4-5	95-96	3-4
1bj	0.31	83.2	61.0	3-4	84-86	3-4

Discussion

It can be seen that the 4,4′-diazobenzanilide derivatives 1A are dyes of yellow or orange shade (°Hue values ranging from 72.6 to 92.7). *C values of up to 65 confirm the good brilliance associated with such structures. A backwater of 11s highly coloured, whereas a backwater of 5 is colourless. As can be seen the dyes of the present invention yield almost colourless backwater and thus show a high substantivity. The maximum degree of exhaustion is 100%. A degree of exhaustion of above 95% can be regarded as excellent, and a degree of exhaustion of above 90% can be regarded as very good. A lightfastness of 1 is very bad, whereas a lightfastness of 8 is the best possible lightfastness. On paper lightfastnesses usually never exceed 6.5, thus the dyes of the present invention exhibit good to very good lightfastnesses.

Claims

1. A 4,4′-diazobenzanilide derivative of the formula

2. A 4-amino-4′-azobenzanilide derivative of the formula

3. A process for the preparation of a 4-amino-4′-azobenzanilide derivative of the formula

4. A process for the preparation of a 4-amino-4′-azobenzanilide derivative of the formula

5. A process for the preparation of a 4,4′-diazobenzanilide derivative of the formula

6. The process for the preparation of the 4,4′-diazobenzanilide derivative of formula (1A)

7. A method of dyeing natural or synthetic materials by applying to the materials the 4,4′-diazobenzanilide derivatives according to claim 1.

8. A method of dyeing paper by applying to the paper the 4,4′-diazobenzanilide derivatives according to claim 1.

9. Paper dyed with a 4,4′-diazobenzanilide derivative according to claim 1.

10. An aqueous formulation comprising a 4,4′-diazobenzanilide derivative according to claim 1.

11. A solid formulation comprising a 4,4′-diazobenzanilide derivative according to claim 1.

12. A process for the preparation of the 4,4′-diazobenzanilide derivative of formula (1A)