Patent GB-816308-A (GB)
Title: Improvements in or relating to water-insoluble monoazo dyestuffs of the benzene-azo-benzene series
IPC: C09B43/18
Filed: 1957-04-25
Abstract: The invention comprises dyestuffs of formula <FORM:0816308/IV (c)/1> where R1 is an alkyl, aralkyl or mononuclear aryl radicle which may be further substituted but which is free from sulphonic or carboxylic acid groups, R2 is an alkyl group of 1-4 C atoms or a carboxylic acid acyl radicle which may be further substituted but which is free from sulphonic or carboxylic acid groups, X is H, OH, alkyl, alkoxy, alkanoylamino or alkylsulphonylamino and it may contain methyl, ethyl, methoxy, ethoxy and alkyl-, alkylamino-, hydroxyalkyl-amino- and alkoxyalkylmino-sulphonyl groups.  They may be made by treating compounds of formula <FORM:0816308/IV (c)/2> <FORM:0816308/IV (c)/3> with appropriate acylating or alkylating reagents.  Especially indicated for R1 are alkyl groups of 1-6 C atoms which may contain hydroxy, ether and/or secondary amino groups, an alkyl radicle substituted by aryl, aryloxy or a hetero-ring and having a total of not more than 11 C atoms, or a phenyl residue which may contain halogen atoms and/or methyl, methoxy, ethoxy and dimethyl- and diethyl-amino groups.  Specified for R2 are acetyl, propionyl, butyryl, isobutyryl, methoxy- and ethoxy-acetyl, 2-methoxy- and ethoxy-propionyl, 3-methoxy-and ethoxy-butyryl, benzoyl, methyl, ethyl, propyl, isopropyl, butyl, isobutyl and 2-cyanoethyl.  The second of the starting dyestuffs may be made by reducing the corresponding nitro dyestuff or from appropriate diazo and coupling components.  The products dye cellulose ester, polyvinyl, polyamide and polyester fibres in yellow to orange shades and mixtures of the dyestuffs may be used. Spinning solutions of cellulose acetate, polyvinyls and polyacrylonitriles may be coloured by certain of the dyestuffs. Some of the products may be used to colour lacquers, oils and synthetic resins and some dye wool, silk and polyacrylonitrile fibres.  Preferred for dyeing cellulose acetate are dyes of formula <FORM:0816308/IV (c)/4> where R3 is H or an alkyl radicle of 1-4 C atoms, R4 is H, OH, alkoxy, dialkylamino or an alkyl radicle of 1-4 C atoms, R5 is an alkyl radicle of 1-4 C atoms, R6 is an alkanoyl radicle of 2-4 C atoms or Me, Et or hydroxyethyl and n is 1-6.  In examples illustrative of the preparation of the dyestuffs and their use in dyeing and colouring processes to provide yellow shades dyestuffs are made corresponding to the last formula in which R3 is Me, R4 is MeO, R5 is Me and R6 is Me and MeCO and dyestuffs of formula <FORM:0816308/IV (c)/5> where y is H and 2-methyl, R1 is ethyl, n-propyl, isopropyl, n-butyl, 2-ethoxyethyl and 3-methoxy-propyl and -butyl and R7 is 31-methyl-, 21-hydroxy-, -ethoxy-, -n-butoxy-, -methyl-, -ethyl-, -methyl- and -n-butyl-sulphonylamino- and -acetyl-, -propionyl-, -butyryl-, -isovaleryl- and chloroacetyl-amino-41-methoxyphenyl, 41-methoxy- and -ethoxyphenyl, 21-methoxy-, -propionyl-, n-butyryl-and -isobutyryl-amino-41-acetoxyphenyl and 21-propionylamino - 41 - propionoxy - phenyl and 21,41-dimethoxyphenyl, and of formula <FORM:0816308/IV (c)/6> where y is H, 2-methyl, ethyl, -methoxy, -ethoxy, -methylsulphonyl, -aminosulphonyl, -methyl-, -ethyl-, 2-(21-hydroxy)-ethyl- and 2-(31-methoxy)-propyl-aminosulphonyl, R1 is methyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, 2-ethyl-butyl, n-hexyl, n-octyl, 1-ethylpentyl, 2-ethylhexyl, 2-methoxy and -ethoxy-ethyl, 2- and 3-methoxypropyl, 2-ethoxypropyl, 3- and 4-methoxybutyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-dimethyl- and -diethyl-aminoethyl, phenyl, 3-methoxy-, 4-ethoxy-, -methyl- and -dimethyl- and -diethylamino-phenyl, 2-phenyl-, -phenoxy- and -morpholyl-ethyl and benzyl and R2 is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 2-cyanoethyl, propionyl, butyryl, isobutyryl, benzoyl, 2-methoxy- and -ethoxy-propionyl, 3-methoxy- and ethoxybutyryl, methoxy- and ethoxy-acetyl and 4-methyl- and -chlorobenzoyl, are also prepared.