GB692372A - New chromiferous monoazo-dyestuffs and process for their manufacture - Google Patents

Abstract

Compounds of the formula <FORM:0692372/IV (b)/1> where A1 and A2 are alkyl or cycloalkyl, X is alkyl, aralkyl or -NR1R2, R1 is hydrogen, alkyl or aralkyl and R2 is hydrogen or alkyl (or -NR1R2 is a morpholino residue) are made as follows: aminohydroquinone dialkyl ether is acylated (e.g. with acetic anhydride) and treated with chlorosulphonic acid to introduce a sulphonyl chloride group; the product is either (1) reacted with HNR1R2 or (2) converted into a sulphinic acid (salt) with alkali bisulphite and condensed with an alkyl or aralkyl halide; finally, in each case the acylamino group is hydrolysed to amino. In specified products A1 and A2 are methyl and -SO2X is sulphonamide, sulphonmethylamide, sulphonethylamide, sulphondiethylamide, sulphonisopropylamide, sulphomorpholide, ethylsulphone and benzylsulphone.ALSO:The invention comprises complex chromium compounds of <FORM:0692372/IV (c)/1> where A2 is alkyl, X is alkyl, aralkyl or -NR1R2, R1 is hydrogen, alkyl or aralkyl, R2 is hydrogen or alkyl (or -NR1R2 is a morpholino group), one Y and one Z are sulphonic acid and the other Y and the other Z are hydrogen. These are made by diazotizing a 2 : 5-dialkoxyaniline having a group -SO2X in the 4-position, coupling with the appropriate naphtholdisulphonic acid and chroming the product under dealkylating conditions. The metal-free dyestuff need not be isolated, the coupling mixture merely being rendered weakly acid before chroming. The alkoxy groups in the nucleus may be substituted and may be cycloalkoxy; groups of 1-4 carbon atoms are preferred. The products are suitable for dyeing and printing wool, silk, leather, superpolyamides and superpolyurethanes. In the examples, the following dyestuffs are made and chromed: (1) 2 : 5-dimethoxyaniline-4-sulphonamide --> 1 - naphthol - 3 : 6 - disulphonic acid; (2) 2 : 5-dimethoxyaniline - 4 - sulphonethylamide --> 1-naphthol-3 : 8-disulphonic acid; and (3) 2 : 5-dimethoxyaniline-4-sulphonethylamide --> 1-naphthol - 4 : 8 - disulphonic acid. A further example shows the dyeing of wool (blue) with the product of (1). Other suitable components are mentioned. Specification 408,590 is referred to.