Cationic (1,4)-diamino anthraquinone dyes prepn. - by amination, halogenation, amination and quaternisation in one-pot process

摘要

Anthraquinone dyes of formula (I):- (in which R1-3 are H, (cyclo)alkyl, aryl, NO2, halogen alkoxy or OH; R4 is H, (cyclo)alkyl, aryl or aralkyl; R5 and R6 are alkyl or H; R7 is (cyclo)alkylene or arylene; R8-10 are (ar)alkyl or aryl, and An is an anion) are prepd. from anthraquinone alpha-sulphonic acid or alpha-bromo anthraquinone (opt. substd. with R1-3) by (A) successive reaction with NH3 or amine R4R5NH to replace the SO3H or NO2 gp., (B) halogenation in 4-posn., (C) condensn with diamine R6NH-R7-NR8R9 and (D) quaternisation, in a one-pot process without intermediate isolation of the prods. The labour-intensive pptn. filtration, washing and drying of the intermediate prods. is eliminated, with ecological advantages and increased yields of =14%. Colour properties of the prods. are at least equal to those from the conventional process.