Verfahren zur Herstellung wasserunloeslicher Styrylfarbstoffe

摘要

Water-insoluble styryl dyes of the formula in which R2 is a pyridylalkyl, a pyridylalkylaminoalkyl or a pyridylalkoxyalkyl residue, R2 is an alkyl group which may be substituted, X is a cyano, carboxylic acid ester, alkyl, aralkyl or arylsulphonyl group or a group of the formula CONR4R5 in which R4 and R5 are hydrogen or an alkyl or aralkyl group and Y1 and Y2 are each hydrogen or halogen atoms or an alkyl or alkoxy group are prepared by (a) condensing an aldehyde of formula the symbols being as above with malodinitrile, a cyanoacetic acid alkyl ester, an alkyl, aralkyl, or arylsulphonylacetonitrile or with a cyanoacetic acid amide, or (b) a styryl derivative of formula in which R2,X,Y1 and Y2 are as above and Z is hydrogen or an hydroxyalkyl group is reacted with a vinylpyridine. Preferably the condensation process (a) is effected by heating in a solvent in presence of a basic catalyst and process (b) is effected in presence of basic or acid catalysts. The dyes give yellow shades on polyacrylonitrile material.ALSO:In Examples 1, 2 and 3, 2-(21-N-methylanilinoethyl) - pyridine, 3 - (21 - N - methylanilinoethyl) - 6 - methylpyridine and the benzoyl ester of N-(21-hydroxyethyl)-N-211-2111 -pyridylethyl-1-3-toluidine are heated with phosphorus oxychloride in dimethylformamide at 60 DEG C., followed by dilution to give the p-aldehydes. In Example 3, N-(21-hydroxyethyl) - N - 211 - 2111 - pyridylethyl - 1,3 - toluidine is prepared from 2-vinylpyridine and N-(21 - hydroxyethyl) - 1 - 3 - toluidine, the product being esterified with benzoyl chloride.