Patent GB-819667-A (GB)
Title: Diazo-oxide compounds of the naphthalene series
IPC: C09B43/06
Filed: 1956-08-16
Abstract: The invention comprises diazo-oxide compounds of the general formula <FORM:0819667/IV (b)/1> wherein X is an aryl azo group which may be substituted by one or more sulphonic acid groups and which is attached to nucleus b in the 4-position, or X is an aryl sulphonyl-oxy group attached to the nucleus a in the 5- or 8-position, wherein the -O--> and N=N-radicals are attached to adjacent carbon atoms, and wherein the nuclei a and b may be further substituted by sulphonic acid groups.  The invention further comprises compounds of the above general formula in which X is a benzene-sulphonyl-oxy group and the -O--> and N = N-radicals are attached to adjacent carbon atoms and which are further substituted by one or more sulphonic acid groups.  Diazo-oxide compounds of the naphthalene series are produced by treating a naphthalene diazonium salt with the diazonium group and a sulphonic acid group attached to adjacent carbon atoms in one nucleus and which is substituted by an aryl azo group in the same nucleus or by an arylsulphonyloxy group in the other nucleus and which may be further substituted by one or more sulphonic acid groups, with an oxidizing agent such as chlorine water, hydrogen peroxide or sodium peroxide in an alkaline medium. Diazo oxides are obtained in examples by oxidizing diazotized amino - azo dyestuffs obtained, diazotizing the products obtained by coupling diazotized 1 - amino - benzene - 4 - sulphonic acid with 1-amino-naphthalene-2-sulphonic acid (1); diazotized 2-amino-naphthalene - 4,8 - disulphonic acid with 1 - aminonaphthalene - 2 - sulphonic acid (2); diazotized 2 - amino - naphthalene - 6,8 - disulphonic acid and 1-amino-naphthalene-2-sulphonic acid (3); and diazotized 2-amino-naphthalene-5,7-disulphonic acid and 1-amino-naphthalene-2-sulphonic acid (4), or by oxidizing diazotized benzene sulphonic esters obtained by diazotizing the products obtained by esterifying 2 - amino - 5 - hydroxy - naphthalene - 1,7-disulphonic acid (5), and 1-amino-8-hydroxynaphthalene - 2,4 - disulphonic acid with benzene sulphochloride in the presence of sodium hydroxide (6). The product (6) is converted to the copper complex of an azo dyestuff (see Group IV (c)).ALSO:The invention comprises diazo oxide compounds of the general formula <FORM:0819667/IV (c)/1> wherein X is an aryl azo group which may be substituted by one or more sulphonic acid groups and which is attached to the nucleus b in the 4-position wherein the -O- and N=N-groups are attached to adjacent carbon atoms and wherein the nuclei a and b may be further substituted by sulphonic groups. Diazo-oxide compounds of the naphthalene series are produced by treating a naphthalene diazonium salt, with the diazonium group and a sulphonic group attached to adjacent carbon atoms in one nucleus and which are substituted by an arylazo group in the same nucleus and which may be further substituted by one or more sulphonic acid groups, with an oxidizing agent such as chlorine water, hydrogen peroxide or sodium peroxide in an alkaline medium.  In examples: Diazo oxides are obtained by treating the monoazo dyestuff obtainable by coupling in acetic acid diazotized 1-amino-benzene-4-sulphonic acid with 1-amino-naphthalene-2-sulphonic acid in water with sodium nitrite and sulphuric acid and oxidizing the product in aqueous sodium carbonate solution with chlorine water (1) and by similarly treating the monoazo dyestuffs obtainable by coupling diazotized 2-aminonaphthalene - 4,8 - disulphonic acid with 1-amino - naphthalene - 2 - sulphonic acid (2); diazotized 2 - amino - naphthalene - 6,8 - disulphonic acid with 1 - amino - naphthalene - 2 - sulphonic acid (4), and diazotized 2-amino-naphthalene-5,7-disulphonic acid with 1-amino-naphthalene-2-sulphonic acid.  The products may be coupled with phenols to form azo dyes.  A copper complex of the sodium salt of 1,11-dihydroxy - 5,51 - di - (benzenesulphonyloxy) 2,21 - azo - naphthalene 7,71 - disulphonic acid is obtained by treating the diazo oxide obtained from the benzene-sulphonic ester of 2-amino-5-hydroxy - naphthalene - 1,7 - disulphonic acid (see Group IV (b)) with ammonia and a solution containing copper sulphate, ammonia and hydroxylamine.