Patent GB-564859-A (GB)
Title: New anthraquinone dyes
IPC: C09B1/30
Filed: 1943-04-12
Abstract: Acid wool dyes are obtained by reaction of a C-aralkyl-cycloaliphatic amine of the general formula H2N-X-(CH2)n-Y, wherein X represents a cycloaliphatic residue, which may be substituted by alkyl, n represents 1, 2 or 3, and Y represents an aryl residue, with an anthraquinone derivative which carries in at least one a -position a substituent capable of reaction with a primary amine and which may carry other substituents other than sulphonic acid groups, and sulphonating the product, either by treatment with a sulphonating agent or, when suitable substituents are present, by reaction with an alkali sulphite.  Such anthraquinone derivative may be used wholly or partly in the leuco form.  Specified amines are the cis- and trans-2-benzyl-cyclohexylamines, 2-benzyl-cyclopentylamine, 6-methyl-2-benzylcyclohexylamine, 2 - p - methoxybenzyl - cyclo - hexylamine, 2-g -phenylpropyl-cyclohexylamine, 2 - o - chlorobenzyl - cyclohexylamine, 2-a -naphthylmethyl - cyclohexylamine and 2 - p - methyl - benzyl - 4 - methyl - cyclohexylamine.  Specified anthraquinone derivatives are quinizarin, the 4-bromo-1-methylamino, 1-chloro, 4-bromo-1-amino-2-methyl, 1 : 4 : 5-trihydroxy, 1 : 4 : 5 : 8-tetrahydroxy, 1 : 4 - diamino, 2 : 4 - dibromo - 1 - amino and 1 : 5-dinitro derivatives of anthraquinone and anthraquinone-1-sulphonic acid.  In examples, (1) trans-2-benzyl-cyclohexylamine is heated with leuco-quinizarin for 42 hours in boiling isobutanol and the product is oxidised by an addition of nitrobenzene and sulphonated with 96 per cent sulphuric acid at 20 DEG  C.; (2) 2-benzyl-cyclopentylamine is similarly heated with quinizarin and leucoquinizarin in butanol and the product similarly oxidised and sulphonated; (3) trans-2-benzylcyclohexylamine is heated with 4-bromo-1-methylamino - anthraquinone and sodium acetate for 6 hours at 190 DEG  C. and the product sulphonated with sulphuric acid monohydrate at 20 DEG  C.; (4) a mixture of cis- and trans-2-benzyl-cyclohexylamine is heated with leucoquinizarin in phenol for 17 hours at 125-130 DEG  C. and the product oxidised and sulphonated as in (1); (5) 6-methyl-2-benzyl-cyclohexylamine is heated with leuco-quinizarin in phenol for 17 hours at 125-130 DEG  C. and the product oxidised and sulphonated as in (1); (6) 2-(p-methoxybenzyl)-cyclohexylamine is heated with leuco-quinizarin in phenol at 125-130 DEG  C. and the product oxidised and sulphonated as in (1); (7) 2-(o-chlorobenzyl)-cyclohexylamine is heated with leuco-quinizarin in phenol at 125-130 DEG  C. and the product oxidised and sulphonated as in (1); (8) 2-benzyl-cyclohexylamine is heated with leuco-1 : 4 : 5-trihydroxyanthraquinone in phenol containing boric acid for 7 hours at 95-100 DEG  C. and the product is oxidised by heating with nitrobenzene and sulphonated as in (1).  Specification 434,429 is referred to. p  C-Aralkyl-cycloaliphatic amines, as above, are obtained (a) by hydrogenation in liquid ammonia, using a nickel catalyst, of the corresponding benzylidene cycloaliphatic ketone, or (b) by reduction, e.g. with sodium and amyl alcohol, of the oximes of the corresponding aralkyl-cycloaliphatic ketones. Aralkyl-cycloaliphatic ketones, as above, are obtained by hydrogenation of the corresponding benzylidene and a  - menaphthylidene - cyclo - hexanones or cyclopentanones, obtained by condensation of the corresponding benzaldehydes or a -naphthaldehydes with the cyclohexanones or cyclopentanones.  2-g -Phenylpropylcyclohexanone is obtained by hydrogenating the product of condensation of cinnamaldehyde with cyclohexanone.