Physicochemical properties of novel methyl 2-{(E)-[(2-hydroxynaphthalen-1-yl)methylidene] amino}-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate as turn-off fluorometric chemosensor for detection Fe3Â + ion

Schiff base (HATC) was synthesized by the reaction of 2-hydroxy-1-naphthaldehyde with methyl 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate. Structure of HATC was confirmed by the EI-MA, IR, 1H NMR, 13C NMR and elemental analysis. Photophysical and physicochemical studies of the HATC such as oscillator strength, extinction coefficient, transition dipole moment, fluorescence quantum yield and stokes shift was investigated in different solvents on the basis of polarities. The observed bathochromic absorbance, emission band and different parameter's on changing the polarity of the solvents. HATC interact with the various metal ions were also studied by spectrofluorophotometer. Schiff base used as on- off type fluorescent chemosensor for sensitive and selective detection of Fe3 + ion. Complexation stoichiometry and mechanism of quenching were determined from Benesi-Hildebrand and Stern-Volmer plot.