Syntheses of (E)-4-(2-(4-methoxyphenyl)diazenyl)benzene 1,3-diol and (E)-1-(2-(4-hydroxyphenyl)diazenyl)-2-naphthol and their application as acid base indicator and in jute dyeing

Depertment of Chemistry, Jadavpur University, Kolkata-700 032, India E-mail : skbhatt7@yahoo.co.in Department of Textile Technology, GCETTS, Hooghly, West Bengal, India Manuscript received 22 January 2014, accepted 31 July 2014 Two novel azo-dyes namely (E)-4-(2-(4-methoxyphenyl)diazenyl)benzene 1,3-diol (L1 ) and (E)-1-(2-(4- hydroxyphenyl)diazenyl)-2-naphthol (L2 ) have been synthesized by the usual method of diazotisation followed by coupling reaction at pH 7.5. The synthesized dyes are characterized by elemental analysis and UV-Vis, IR, 1H NMR, mass spectrophotometry. These synthesised compounds are found to exhibit significant dyeing property on bleached jute substrate under neutral and particularly basic pH condition with good colour yield and wash fastness. Moreover the acid base indicator property of L2 being more prominent than that of L1 , the parameters measuring the performance of the former as an indicator have also been evaluated spectrophotometrically and condutometrically in this paper. The study shows better performance of L2 than methyl orange, particularly for titration of dilute solutions. The antibacterial activity of both L1 and L2 has also been studied, where L2 showed more significant effect than L 1