2‐(4‐alkylamido‐2‐hydroxyphenyl)benz‐X‐azoles as intermediates for the synthesis of dyes

Nineteen substituted 2‐phenylbenz‐X‐azoles, which are intermediates for the synthesis of dyes, were prepared from p ‐aminosalicylic acid (PAS). Substituents in the phenyl ring are 2′‐hydroxy and/or 4′‐amino and 4′‐alkylamido with alkyl chains ranging from C 1 to C 15 . The preferred route of the synthesis is discussed. The melting points and the R f values are correlated with the structure. An extensive discussion of the electronic absorption spectra, involving other compounds with the same general structure, is reported.