Patent GB-852518-A (GB)
Title: Process for the manufacture of salts of sulphuric acid esters of leuco vat dyestuffsof the anthraquinone series
IPC: C09B9/02
Filed: 1956-10-25
Abstract: Water-soluble salts of sulphuric esters of leuco vat dyes which are difficult to esterify (as determined by the test given in Specification 719,621) are made by treating the dye in a mixture of pyridine or a homologue thereof (or a mixture of such) with one or more tertiary amines containing the grouping:  <FORM:0852518/IV (c)/1> in which (a) there are bound to the nitrogen atom either two saturated hydrocarbon radicals together containing at least three and at most eleven carbon atoms or a single saturated divalent hydrocarbon radical forming together with nitrogen atom a heterocyclic ring, each of said hydrocarbon radicals containing at most 7 carbon atoms, and in which there are bound to the carbon atom two saturated hydrocarbon radicals together containing at most eight carbon atoms, or, when the nitrogen atom forms part of a heterocyclic ring a single saturated divalent hydrocarbon radical forming together with the carbon atom a carbocylic ring, each of said hydrocarbon radicals containing at most 6 carbon atoms, or (b) in which there are bound to the carbon atom a methyl group and to the nitrogen atom a saturated hydrocarbon radical containing at most 7 carbon atoms and the carbon and nitrogen atoms are also jointly bound to a saturated divalent hydrocarbon radical forming with them a heterocyclic ring, said mixture containing 10-60% by weight of said tertiary amine, in presence of finely divided iron, cobalt, zinc, copper, or a copper alloy, with chlorsulphonic acid in the form of its addition products with said bases, the chlorsulphonic acid being present in at least two molecular proportions and the metal at least 1, 5 atomic proportions, for each anthraquinone nucleus in the vat dye, and at least 1, 4 mols of said tertiary amine or amines for every 2 mols chlorsulphonic acid, except that at least 2 mols are used if less than four mols chlorsulphonic acid are used.  The ester compound so obtained is finally converted to a water-soluble salt. Pyridine homologues specified are a -, b -, or g - picoline, 2 : 4-, or 2 : 6- butidine, or 2-methyl -5- ethylpyridine.  Four classes of tertiary amine are specified, viz. those of the formulae:  <FORM:0852518/IV (c)/2> in which R1, R3, and R4 represent methyl, ethyl, propyl, or butyl, and R2 is ethyl, propyl, isopropyl, or butyl; <FORM:0852518/IV (c)/3> in which X represents a pentamethylene or tetramethylene group which may be substituted by methyl, and R3 and R4 represent methyl, ethyl, propyl, or butyl; <FORM:0852518/IV (c)/4> in which R1 is methyl, ethyl, propyl, or butyl, R4 is methyl, and X is a tetramethylene group which may be substituted by methyl; <FORM:0852518/IV (c)/5> in which X and Y are pentamethylene or tetramethylene groups which may be substituted by methyl.  The metal may be etched as described in Specifications 745,088 and 745,368. Watersoluble salts comprise the lithium, sodium, potassium, ammonium, and hydroxy-alkylamine salts.  In examples, the following dyes are converted to leuco-sulphuric ester salts by the above process: 1, 4- or 1, 5- dibenzoylaminoanthraquinone, 1- (41- dimethylsulphonamidobenzoylamino) -4 -(411- chlorobenzoylamino or benzoylamino)- anthraquinone, carbazolized di- (51-benzoylamino -11- anthrquinonyl) -2, 8-diaminochrysene, carbazolized 81, 811- dibenzoylamino -1, 4, 11, 111- trianthrimide, the anthrimide from 1, 3- dichloro -2- methylanthraquinone and 1, 4- monobenzoyldiaminoanthraquinone, using as bases pyridine and homologues thereof specified above together with the tertiary amines listed below and grouped as under classes 1-4 above: (1) diethyl-isopropylamine, ethyldiisopropylamine, diethyl 3- amylamine, ethyl npropylisopropylamine, ethyl n-butyl isopropylamine, methyl ethyl isopropylamine, diethyl secbutylamine, diethyl -3-amylamine, diethyl -4- heptylamine, diethyl -5-nonylamine, (2) N-isopropyl -2- methylpiperidine, N-3-amylpiperidine, N-4-heptylpyrrolidine, N- isopropylpiperidine, N- secbutylpiperidine, (3) N- nbutyl -2, 6- dimethylpiperidine, N- methyl -2, 6- dimethylpiperidine, N- ethyl- 2, 6- dimethylpiperidine, N-ethyl -2-methylpiperidine, N- npropyl -2- methylpiperidine, N- nbutyl -2- methylpiperidine; (4) N- cyclopentylpiperidine, N- cyclopentyl -2-methylpiperidine, N- cyclohexylpiperidine, N-cyclohexylpyrrolidine, N- 4- methylcyclohexylpiperidine, N -3- methylcyclohexyl -2- methylpiperidine, N -4- methylcyclohexyl -2- methylpiperidine, N -3- methylcyclohexylpyrrolidine, N -4- methylcyclohexylpyrrolidine. Specification 745,365 also is referred to.