Abstract
Reaction of 2,3-dichloro-5,6-dicyanopyrazine with various Fisher's base type enamines gave the corresponed 2-chloro-5,6-dicyanopyrazine derivatives. The reactive-disperse dye showed large differences in ${\lambda}_{max}$ from solution to solid state resulting from strong intermolecular π-π interactions. These dyes have rather small molecular size but have a strong intermolecular charge-transfer chromophoric system. The absorption maxima of these compounds were observed at 463∼560 nm. The electronic character of the substituents in dyes strongly after their absorption spectra, producing bathochromic shifts depending on both the basicity of the heterocyclic moiety and the enlargement of the π-conjugated system. The dyeability of the two dyes toward polyester and nylon fiber were generally good. Wash, perpiration and rubbing fastness were excellent, while light fastness was poor probably due to the oxidation of the enamine moity.