Abstract
Fifteen new chromophoric chain ?-substituted butamethine asycyanine (CCBSBA) colorants have been synthesized by catalytic condensation of (i) 4- Dimethylaminostyrylphenyl ketone ; (ii) 4- Dimethylaminostyryl-3’- nitrophenyl ketone and (iii) 4-Dimetjylaminostyryl-3’-methylphenyl ketone with 2-methyl-3-(1-methylethyl)benzothiazolium iodide and 2-methyl-6-substituted-3-(1-methylethyl)benzothiazolium iodides using piperidine as basic catalyst and ethanolic DMF as solvent. These colorants were synthesized with the object to study the impact of various functional groups and chain enhancement and shortage of prime chain on visible electronic spectra. All the colorants showed increase in electronic spectra whether electron withdrawing or donating. These colorants led to red shifts of the electronic spectra w.r.t. the previously reported styryl chain asycyanino-colorants, and to blue shifts of electronic spectra w.r.t. previously reported asycyanine colorants having quinoline moiety.