Azo dyes
The present invention relates to compounds of the formula I ##STR2## where 
     A 1  is fluorine, chlorine, bromine, cyano, trifluoromethyl, C 1  -C 4  -alkylsulfonyl or substituted carbamoyl, 
     A 2  is hydrogen, chlorine, bromine or methyl, 
     A 3  is hydrogen, chlorine, bromine, carboxylic acid ester, cyano, trifluoromethyl, substituted carbamoyl, methyl, ethyl, methoxy or ethoxy, 
     A 4  is hydrogen, methyl, methoxy or ethoxy, 
     R is hydrogen, amino, methyl, ethyl or propyl, 
     R 1  is hydrogen, substituted or unsubstituted C 1  -C 8  -alkyl, hydroxyl or amino and 
     X is cyano, carbamoyl or hydrogen. 
     Examples of radicals A 1 , in addition to those already mentioned, are methylsulfonyl, ethylsulfonyl, butylsulfonyl and radicals of the formula ##STR3## where R 2  and R 3  are C 1  -C 8  -alkyl which may or may not be substituted by C 1  -C 4  -alkoxy, and R 2  may also be hydrogen. 
     Specific examples of carbamyl radicals A 1  (and also of A 3 ) are: ##STR4## 
     Carboxylic acid ester groups A 3  are in particular those of 1 to 8 carbon atoms, examples being: ##STR5## 
     Examples of substituted or unsubstituted alkyl radicals R 1  are alkyl radicals of 1 to 4 carbon atoms which may be substituted by C 1  -C 4  -alkoxy, alkanoylamino or alkoxycarbonylamino. Specific examples are: CH 3 , C 2  H 5 , n- and i-C 3  H 7 , n- and i-C 4  H 9 , C 2  H 4  OCH 3 , C 2  H 4  OC 2  H 5 , C 2  H 4  OC 3  H 7 , C 2  H 4  OC 4  H 9 , C 3  H 6  OCH 3 , C 3  H 6  OC 2  H 5  and C 3  H 6  OC 4  H 9  and CH 2  NHCOCH 3 , CH 2  NHCOCH 2  H 5 , CH 2  NHCOC 3  H 7 , CONHCOOCH 3 , CH 2  NHCOOC 2  H 5 , CH 2  NHCOOC 4  H 9   and ##STR6## 
     A compound of the formula I may be prepared by reacting a diazo compound of an amine of the formula II ##STR7## with a coupling component of the formula III ##STR8## 
     Details of the reactions may be found in the Examples, where parts and percentages are by weight, unless stated otherwise. 
     Compounds of particular importance are those of the formula I a ##STR9## where A 1  and A 3  have the stated meanings. 
     The compounds of the formula I may be used for dyeing synthetic fibers, especially polyesters. They give orange to red dyeings distinguished by good fastness characteristics, eg. good lightfastness and fastness to dry heat pleating and setting. In certain cases, the tinctorial strength is very high. 
    
    
     EXAMPLE 1 
     9.3 parts of 4-chloro-4&#39;-amino-azobenzene are dissolved in 100 parts of warm glacial acetic acid, the solution is then cooled to room temperature, 15 parts by volume of concentrated hydrochloric acid are added and the mixture is cooled to 10°-12° C. 14 parts by volume of a 23 percent strength aqueous sodium nitrite solution are then added at 10°-14° C. and the mixture is stirred for 21/2 hours at 10°-15° C. After destroying excess nitrous acid with amidosulfonic acid, the diazonium salt mixture is run into a solution prepared by heating 6.0 parts of 2,6-dihydroxy-3-cyano-4-methyl-pyridine in 200 parts by volume of water and 4 parts of 50 percent strength sodium hydroxide solution, and then cooling to 0° C. by adding ice. During the addition of the diazo component, sodium hydroxide solution is added to the coupling mixture so as to prevent the pH from falling below 4.5. 
     After completion of coupling, the mixture is heated at 80°-90° C. at pH 4.5-8 and the dye which has precipitated is filtered off as soon as the heat treatment has produced the desired crystal size, and is washed salt-free. After drying, 15.3 parts of a brown powder are obtained. The dye has the formula ##STR10## and dyes polyethylene terephthalate fabric, by the high temperature process (at 125°-140° C.), in deep orange hues having good lightfastness and fastness to dry heat pleating and setting. The dye is very economical in use. 
     EXAMPLE 2 
     8.9 parts of 4-cyano-4&#39;-amino-azobenzene are diazotized by the method described in Example 1 and excess nitrous acid is destroyed. 6.6 parts of 1,4-dimethyl-2-hydroxy-3-cyanopyrid-6-one are dissolved in 200 parts by volume of water and 4 parts of 50 percent strength sodium hydroxide solution and are cooled to 0° C. with ice, after which the diazonium salt mixture is run in slowly, with thorough stirring, whilst keeping the pH at from 4.5 to about 9 by simultaneous addition of dilute sodium hydroxide solution. The coupling is completed rapidly. The suspension is heated to 70°-80° C. and is kept at this temperature for some time, and the dye which has precipitated is filtered off hot. After washing and drying, 15.5 parts of a reddish brown powder of the formula ##STR11## are obtained; this product dyes polyethylene terephthalate in orange hues having good lightfastness and fastness to dry heat pleating and setting. 
     EXAMPLE 3 
     9.8 parts of 4-chloro-3&#39;-methyl-4&#39;-amino-azobenzene are stirred into 50 parts by volume of glacial acetic acid. 2 parts of concentrated sulfuric acid are added, followed, at 10°-15° C., by 14 parts of a 42 percent strength nitrosylsulfuric acid solution. The diazotization mixture is stirred for 11/2 hours at 15° C. and after destroying the excess nitrous acid the mixture is combined with a solution of 5.5 parts of 2,6-dihydroxynicotinonitrile in 200 parts by volume of water and 4 parts of 50 percent strength sodium hydroxide solution, using a procedure similar to that described in Examples 1 and 2. After isolating the product in the conventional manner, 15.2 parts of a reddish brown powder of the formula ##STR12## are obtained; this product dyes polyethylene terephthalate fabric in reddish orange hues which are lightfast and fast to dry heat pleating and setting. 
     The dyes characterized in the Table below by specifying the substituents are also obtained by methods similar to that described above. 
     
                                           TABLE 1                                 
__________________________________________________________________________
 ##STR13##                                                                
No.                                                                       
   A.sup.1         A.sup.2                                                
                     A.sup.3                                              
                            R.sup.1   Hue                                 
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4  Cl              H H      CH.sub.3  orange                              
5  &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      &#34;                                   
6  &#34;               &#34; &#34;      C.sub.3 H.sub.7 (n)                           
                                      &#34;                                   
7  &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      &#34;                                   
8  &#34;               &#34; &#34;      C.sub.4 H.sub.9 (i)                           
                                      &#34;                                   
9  &#34;               &#34; &#34;      CH.sub.2 CH.sub.2 OCH.sub.3                   
                                      &#34;                                   
10 &#34;               &#34; &#34;      CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3          
                                      &#34;                                   
11 &#34;               &#34; CH.sub.3                                             
                            CH.sub.3  &#34;                                   
12 &#34;               Cl                                                     
                     H      C.sub.4 H.sub.9 (n)                           
                                      &#34;                                   
13 &#34;               &#34; CH.sub.3                                             
                            &#34;         reddish                             
                                      orange                              
14 CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2                           
                   H H      CH.sub.3  orange                              
15 &#34;               &#34; CH.sub.3                                             
                            &#34;         reddish                             
                                      orange                              
16 CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2                           
                   H CH.sub.3                                             
                            C.sub.2 H.sub.5                               
                                      reddish                             
                                      orange                              
17 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      reddish                             
                                      orange                              
18 &#34;               Cl                                                     
                     &#34;      &#34;         red                                 
19                                                                        
    ##STR14##      H H      H         orange                              
20 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
21 &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      &#34;                                   
22 &#34;               &#34; Cl     H         reddish                             
                                      orange                              
23 &#34;               &#34; &#34;      CH.sub.3  reddish                             
                                      orange                              
24 &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      reddish                             
                                      orange                              
25 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      reddish                             
                                      orange                              
26 &#34;               &#34; CH.sub.3                                             
                            H         reddish                             
                                      orange                              
27                                                                        
    ##STR15##      H OCH.sub.3                                            
                            H         red                                 
28 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
29 &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      &#34;                                   
30 &#34;               &#34; COOCH.sub.3                                          
                            CH.sub.3  &#34;                                   
31                                                                        
    ##STR16##      H COOCH.sub.3                                          
                            C.sub.2 H.sub.5                               
                                      &#34;                                   
32 &#34;               &#34; COOC.sub.2 H.sub.5                                   
                            H         &#34;                                   
33 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
34 &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      &#34;                                   
35 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      &#34;                                   
36 C.sub.4 H.sub.9 (n)NHCO                                                
                   &#34; H      H         orange                              
37 &#34;               &#34; CH.sub.3                                             
                            &#34;         &#34;                                   
38 &#34;               &#34; H      CH.sub.3  &#34;                                   
39 &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      &#34;                                   
40 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      &#34;                                   
41 &#34;               &#34; OCH.sub.3                                            
                            CH.sub.3  red                                 
42 &#34;               Cl                                                     
                     H      H         orange                              
43 CH.sub.3 OCH.sub.2 CH.sub.2 CH.sub.2 NHCO                              
                   H &#34;      &#34;         &#34;                                   
44 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
45 &#34;               &#34; &#34;      C.sub.2 H.sub.5                               
                                      &#34;                                   
46 &#34;               &#34; CH.sub.3                                             
                            H         &#34;                                   
47 CH.sub.3 OCH.sub.2 CH.sub.2 CH.sub.2 NHCO                              
                   H CH.sub.3                                             
                            CH.sub.3  &#34;                                   
48 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      &#34;                                   
49 &#34;               Cl                                                     
                     &#34;      H         &#34;                                   
50 CH.sub.3 OCH.sub.2 CH.sub.2 NHCO                                       
                   H H      C.sub.4 H.sub.9 (n)                           
                                      &#34;                                   
51 &#34;               Cl                                                     
                     &#34;      &#34;         &#34;                                   
52 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
53 &#34;               &#34; &#34;      H         &#34;                                   
54 &#34;               &#34; CH.sub.3                                             
                            &#34;         &#34;                                   
55 C.sub.6 H.sub.13 (n)NHCO                                               
                   H &#34;      CH.sub.3  &#34;                                   
56 &#34;               &#34; &#34;      CH.sub.2 CH.sub. 2 OCH.sub.3                  
                                      &#34;                                   
57 (i)C.sub.8 H.sub.17 NHCO                                               
                   &#34; H      H         &#34;                                   
58 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
59 &#34;               &#34; Cl     H         red                                 
60 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
61 C.sub.2 H.sub.5 NHCO                                                   
                   &#34; COOC.sub.2 H.sub.3                                   
                            &#34;         &#34;                                   
62 C.sub.4 H.sub.9 (n)NHCO                                                
                   &#34; &#34;      &#34;         &#34;                                   
63 Br              H H      H         orange                              
64 Cl              &#34; Cl     CH.sub.2 CH.sub.2 OCH.sub.3                   
                                      &#34;                                   
65 CH              &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      reddish                             
                                      orange                              
66 C.sub.4 H.sub.9 (n)NHCO                                                
                   Cl                                                     
                     &#34;      &#34;         reddish                             
                                      orange                              
67 CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2                           
                   H CF.sub.3                                             
                            &#34;         reddish                             
                                      orange                              
68                                                                        
    ##STR17##      &#34; CN     CH.sub.3  reddish orange                      
69 &#34;               &#34; &#34;      H         reddish                             
                                      orange                              
70                                                                        
    ##STR18##      &#34; H      &#34;         orange                              
71 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
72                                                                        
    ##STR19##      &#34; &#34;      &#34;         &#34;                                   
73                                                                        
    ##STR20##      &#34; &#34;      H         &#34;                                   
74 &#34;               &#34; &#34;      CH.sub.3  &#34;                                   
75 &#34;               &#34; CH.sub.3                                             
                            H         reddish                             
                                      orange                              
76 &#34;               &#34; H      C.sub.4 H.sub.9 (n)                           
                                      orange                              
77 &#34;               &#34; CH.sub.3                                             
                            &#34;         reddish                             
                                      orange                              
78 Cl              &#34; CON(CH.sub.3).sub.2                                  
                            H         reddish                             
                                      orange                              
79 Cl              Cl                                                     
                     COH(CH.sub.3).sub.2                                  
                            CH.sub.3  reddish                             
                                      orange                              
80 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      reddish                             
                                      orange                              
81 &#34;               H COH(C.sub.2 H.sub.5).sub.2                           
                            H         reddish                             
                                      orange                              
82 &#34;               &#34; &#34;      C.sub.4 H.sub.9 (n)                           
                                      reddish                             
                                      orange                              
83 &#34;               Cl                                                     
                     Cl     &#34;         reddish                             
                                      orange                              
84 H               Cl                                                     
                     H      H         orange                              
85 Cl              Cl                                                     
                     &#34;      &#34;         &#34;                                   
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                                           TABLE 2                                 
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 ##STR21##                                                                
No.                                                                       
   A.sup.1    A.sup.2                                                     
                 A.sup.3                                                  
                        A.sup.4                                           
                           X    R    R.sup.1                              
                                          Hue                             
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86 Cl         H  H      H  CN   CH.sub.3                                  
                                     H    orange                          
87 &#34;          &#34;  &#34;      &#34;  &#34;    &#34;    CH.sub.3                             
                                          &#34;                               
88 &#34;          &#34;  C.sub.2 H.sub.5                                          
                        &#34;  &#34;    &#34;    H    orange                          
89 &#34;          Cl H      &#34;  &#34;    &#34;    CH.sub.3                             
                                          orange                          
90 &#34;          &#34;  &#34;      &#34;  &#34;    H    &#34;    &#34;                               
91 H          &#34;  Cl     H  H    CH.sub.3                                  
                                     H    &#34;                               
92 &#34;          &#34;  &#34;      &#34;  &#34;    &#34;    CH.sub.3                             
                                          &#34;                               
93 &#34;          &#34;  &#34;      &#34;  &#34;    &#34;    C.sub.4 H.sub.9 (n)                  
                                          &#34;                               
94 Cl         &#34;  H      &#34;  &#34;    &#34;    &#34;    &#34;                               
95 &#34;          &#34;  Cl     &#34;  &#34;    &#34;    H    orange                          
96 &#34;          H  CH.sub.3                                                 
                        Cl CN   &#34;    &#34;    reddish                         
                                          orange                          
97 Cl         H  H      H  CN   C.sub.2 H.sub.5                           
                                     H    orange                          
98 &#34;          &#34;  &#34;      &#34;  &#34;    C.sub.3 H.sub.7 (n)                       
                                     &#34;    orange                          
99 &#34;          &#34;  CON(C.sub.2 H.sub.5).sub.2                               
                        &#34;  &#34;    CH.sub.3                                  
                                     C.sub.2 H.sub.5                      
                                          &#34;                               
100                                                                       
   &#34;          &#34;  &#34;      &#34;  &#34;    C.sub.2 H.sub.5                           
                                     CH.sub.3                             
                                          &#34;                               
101                                                                       
   &#34;          &#34;  &#34;      Cl &#34;    CH.sub.3                                  
                                     C.sub.4 H.sub.9 (n)                  
                                          &#34;                               
102                                                                       
   CH.sub.3 (CH.sub.2).sub.3 SO.sub..sub.2                                
              Cl &#34;      H  &#34;    &#34;    &#34;    &#34;                               
103                                                                       
   &#34;          &#34;  CH.sub.3                                                 
                        &#34;  &#34;    &#34;    &#34;    reddish                         
                                          orange                          
104                                                                       
    ##STR22## H  H      &#34;  CN   &#34;    H    orange                          
105                                                                       
   &#34;          &#34;  CN     &#34;  H    &#34;    C.sub.4 H.sub.9 (n)                  
                                          &#34;                               
106                                                                       
    ##STR23## &#34;  H      &#34;  CN   &#34;    &#34;    &#34;                               
107                                                                       
    ##STR24## &#34;  CH.sub.3                                                 
                        &#34;  &#34;    &#34;    &#34;    &#34;                               
108                                                                       
   Cl         &#34;  &#34;      CH.sub.3                                          
                           CONH.sub.2                                     
                                &#34;    &#34;    &#34;                               
109                                                                       
   &#34;          Cl Cl     H  &#34;    &#34;    H    reddish                         
                                          orange                          
110                                                                       
    ##STR25## H  Cl     H  CONH.sub.2                                     
                                CH.sub.3                                  
                                     C.sub.2 H.sub.5                      
                                          orange                          
111                                                                       
   Br         &#34;  H      &#34;  CN   &#34;    H    orange                          
112                                                                       
   Cl         &#34;  COOC.sub.2 H.sub.5                                       
                        &#34;  &#34;    &#34;    C.sub.2 H.sub.5                      
                                          reddish                         
                                          orange                          
113                                                                       
   Cl         CH.sub.3                                                    
                 H      H  CN   &#34;    H    orange                          
114                                                                       
   &#34;          H  &#34;      &#34;  H    &#34;    &#34;    yellow                          
115                                                                       
   &#34;          CH.sub.3                                                    
                 &#34;      &#34;  CN   OH   &#34;    &#34;                               
116                                                                       
   &#34;          H  &#34;      &#34;  &#34;    &#34;    CH.sub.3                             
                                          &#34;                               
117                                                                       
   &#34;          &#34;  &#34;      &#34;  &#34;    NH.sub.2                                  
                                     H    &#34;                               
118                                                                       
   &#34;          &#34;  &#34;      &#34;  &#34;    &#34;    CH.sub.3                             
                                          &#34;                               
119                                                                       
   &#34;          CH.sub.3                                                    
                 &#34;      &#34;  &#34;    &#34;    &#34;    &#34;                               
120                                                                       
   &#34;          &#34;  &#34;      &#34;  &#34;    &#34;    H    &#34;                               
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                                           TABLE 3                                 
__________________________________________________________________________
 ##STR26##                                                                
No.                                                                       
   A.sup.1     A.sup.2                                                    
                 A.sup.3       A.sup.4                                    
                                  R    R.sup.1                            
                                            Hue                           
__________________________________________________________________________
121                                                                       
   Cl          H H             H  C.sub.2 H.sub.5                         
                                       H    orange                        
122                                                                       
   &#34;           &#34; &#34;             &#34;  C.sub.3 H.sub.7 (n)                     
                                       &#34;    &#34;                             
123                                                                       
   &#34;           &#34; CH.sub.3      CH.sub.3                                   
                                  CH.sub.3                                
                                       C.sub.4 H.sub.9 (n)                
                                            reddish                       
                                            orange                        
124                                                                       
    ##STR27##  &#34; &#34;             &#34;  &#34;    &#34;    reddish orange                
125                                                                       
   CH.sub.3 O(CH.sub.2).sub.3 NHCO                                        
               &#34; &#34;             &#34;  &#34;    &#34;    reddish                       
                                            orange                        
126                                                                       
   Cl          Cl                                                         
                 H             H  &#34;    H    orange                        
127                                                                       
   &#34;           H CH.sub.3      Cl &#34;    C.sub.4 H.sub.9 (n)                
                                            &#34;                             
128                                                                       
   CH.sub.3 (CH.sub.2).sub.3 SO.sub.2                                     
               H H             H  CH.sub.3                                
                                       H    &#34;                             
129                                                                       
   C.sub.4 H.sub.9 (n)NHCO                                                
               &#34; &#34;             CH.sub.3                                   
                                  &#34;    &#34;    &#34;                             
130                                                                       
   &#34;           &#34; &#34;             &#34;  &#34;    CH.sub.3                           
                                            &#34;                             
131                                                                       
   &#34;           &#34; &#34;             &#34;  &#34;    C.sub.4 H.sub.9 (n)                
                                            &#34;                             
132                                                                       
   Cl          Cl                                                         
                 COOC.sub.4 H.sub.9 (n)                                   
                               H  &#34;    &#34;    &#34;                             
133                                                                       
   &#34;           &#34; COOC.sub.2 H.sub.4 OCH.sub.3                             
                               &#34;  &#34;    &#34;    &#34;                             
134                                                                       
   &#34;           H COOC.sub.2 H.sub.4 OC.sub.2 H.sub.4 OC.sub.4 H.sub.9     
                               &#34;n)                                        
                                  &#34;    &#34;    &#34;                             
135                                                                       
    ##STR28##  &#34; CN            &#34;  &#34;    &#34;    reddish orange                
136                                                                       
   &#34;           &#34; &#34;             &#34;  &#34;    C.sub.2 H.sub.5                    
                                            reddish                       
                                            orange                        
137                                                                       
   Cl          &#34; H             &#34;  NH.sub.2                                
                                       H    yellow                        
138                                                                       
   &#34;           &#34; &#34;             &#34;  &#34;    CH.sub.3                           
                                            &#34;                             
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                       Table 4                                                     
______________________________________                                    
 ##STR29##                                                                
                                         Hue on                           
No.  A.sup.1                                                              
            A.sup.3  R     R.sup.1                                        
                                 X       polyester                        
______________________________________                                    
139  H      H        CH.sub.3                                             
                           H     H       golden                           
                                         yellow                           
140  &#34;      &#34;        H     &#34;     &#34;       golden                           
                                         yellow                           
141  &#34;      OCH.sub.3                                                     
                     CH.sub.3                                             
                           &#34;     &#34;       red                              
142  &#34;      CH.sub.3 &#34;     &#34;     &#34;       orange                           
143  Cl     H        &#34;     &#34;     &#34;       &#34;                                
144  &#34;      &#34;        &#34;     &#34;     CONH.sub.2                               
                                         &#34;                                
145  H      &#34;        &#34;     &#34;     &#34;       &#34;                                
146  &#34;      &#34;        NH.sub.2                                             
                           CH.sub.3                                       
                                 CN      yellow                           
147  &#34;      OCH.sub.3                                                     
                     CH.sub.3                                             
                           &#34;     H       red                              
148  &#34;      &#34;        &#34;     C.sub.2 H.sub.5                                
                                 &#34;       &#34;                                
149  &#34;      &#34;        &#34;     C.sub.3 H.sub.7                                
                                 &#34;       &#34;                                
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