Patent GB-491493-A (GB)
Title: New anthraquinone compounds
IPC: C09B1/26
Filed: 1937-02-01
Abstract: A leuco derivative of a compound of the formula <FORM:0491493/IV/1> (in which R1 stands for amino or hydroxy, R2 stands for R1 or alkylamino, cycloalkylamino or arylamino, and n = O, 1, or 2) is reacted with an amine or amines of either the formula <FORM:0491493/IV/2> or the formula <FORM:0491493/IV/3> oxidizing the resulting leuco derivative, and sulphonating. Starting materials specified are on the one hand, leuco-quinizarin, leuco-1.4.5-tri- and 1.4.5.6- and 1.4.5.8-tetra-hydroxyanthraquinones, leuco - 1 - anilino - 4 - hydroxyanthraquinone, leuco - 1.4 - diaminoanthraquinone and leuco-1-amino-4-anilinoanthraquinone, and on the other a -phenyl-b -aminopropane, a -phenyl-b -aminobutane, a g -diphenyl - b  - aminopropane, a  - phenyl - g -aminobutane and a e -diphenyl-y-aminopentane.  The reaction is effected by heating in a diluent or in excess of the amine.  One or two groups in the anthraquinone body may be replaced, if desired by different amines, and the preparation of the leuco starting material by reduction may be combined with the reaction.  One or more sulphonic acid groups may be introduced.  The products dye wool blue, greenish-blue, or violet shades fast to washing, milling and light.  In examples: (1) leuco-quinizarin is reacted in pyridine with a g  - diphenyl - b  - aminopropane, followed by oxidation using a current of air and sulphonation to give 1.4-bis-(dibenzyl-methylamino) - anthraquinone sulphonic acid; the a y - diphenyl - b  - aminopropane may be replaced by a -phenyl-b -aminobutane; (2) leucoquinizarin is reacted with a e -diphenyl-g -aminopentane, followed by oxidation and sulphonation to give 1.4-bis-(b .b 1-dibenzyl-isopropylamino) - anthraquinone sulphonic acid; (3) leuco-quinizarin is reacted with a -phenyl-b -aminopropane in pyridine, followed by oxidation and sulphonation to give 1.4-bis - (b  - phenyl - isopropylamino) - anthraquinonesulphonic acid; the a -phenyl-b -aminopropane may be replaced by a -phenyl-g -aminobutane; (4) leuco-1.4.5-trihydroxyanthraquinone is reacted with a g -diphenyl-b -aminopropane in cresylic acid, followed by oxidation and sulphonation to give 1.4-bis-(b .b 1 - dibenzylmethylamino) - 5 - hydroxyanthraquinonesulphonic acid; a e -diphenyl-g -aminopentane may also be used as amine; (5) 1 - p - toluidino - 4 - hydroxyanthraquinone is reacted with a g -diphenyl-b -aminopropane in cresylic acid in presence of zinc dust, followed by oxidation and sulphonation to give 1-dibenzylmethylamino - 4 - p - toluidinoanthraquinonesulphonic acid; 1-hydroxy-4-p-n-butylanilinoanthraquinone may be used instead of 1 - p -toluidino - 4 - hydroxyanthraquinone; (6) leuco-quinizarin is reacted with a e -diphenyl-g -aminopentane in cresylic acid as in (5) to give 1-b b 1-dibenzylisopropylamino-4 -hydroxyanthraquinonesulphonic acid; (7) leuco -1.4-diaminoanthraquinone is reacted with a q -diphenyl-b -aminopropane and worked up as in (1) to give the same product as in (1).  a g  - Diphenyl - b  - aminopropane is made by reacting dibenzyl ketone with ammonium formate or formamide and hydrolysing the resulting formyldiphenylisopropylamine. a .e -Diphenyl-g -aminopentane is made from dibenzylacetone similarly and b -phenyl-a -aminopropane from benzyl methyl ketone.