Azo dyes containing 2-amino-3-cyano-5-formylthiophene derivatives as diazo components and substituted aniline compounds as coupling components

摘要

The compounds of the formula I (I) where R is unsubstituted or substituted phenyl or naphthyl, R1 and R2 are each unsubstituted or substituted alkyl, alkenyl or cycloalkyl, and one of the radicals may furthermore be hydrogen, R3 is hydrogen, methyl, methoxy, ethoxy or chlorine, and R4 is acylamino, are particularly useful for dyeing polyesters.