Xanthene dyes prepd. from 9-phenyl xanthene cpds. - by reaction with amines using Lewis acid catalysts (BE060876)

摘要

Xanthene dyes are prepd. by reaction of 9-phenyl xanthene cpds. of formula (in which R3 and R4 are H, halogen alkyl or alkoxy, or together form a heterocyclic or carbocyclic ring; R5 is H or alkyl; Y is halogen or alkoxy; Z is hydroxy or alkoxy or the gp. of an organic or inorganic acid) with prim. or sec. aromatic or heterocyclic amines, in presence of a Lewis acid, in which the amine is used as solvent. Used for spin-dyeing of polyacrylonitrile fibres, and after sulphonation as water-soluble dyes for wool, silk or synthetic fibres suitable for acid dyes. The dyes have high purity and colour strength, and can be readily isolated from the reaction mixt. by a variety of methods e.g. filtering off as the cryst. salt, conversion to the dye base by reaction with aq. alkali and removal of excess amine by filtration or steam-distn. etc.