Synthesis, spectrophotometric and DFT studies of new Triazole Schiff bases as selective naked-eye sensors for acetate anion


Balakit A. A. , Makki S. Q. , SERT Y., UCUN F. , Alshammari M. B. , Thordarson P., ...Daha Fazla

SUPRAMOLECULAR CHEMISTRY, 2020 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

Selective anion sensors can be used in the colourimetric detection of certain anions. In the present study, two new 1,2,4-triazole derivatives containing thiol group and azo moiety3a(nitrile derivative) and3b(methoxy derivative) were synthesised by condensation of 4-(4-amino-5-mercapto-4 H-1,2,4-triazol-3-yl)phenol (1) and aromatic aldehydes containing azo groups2aand2bunder acidic conditions. The nitrile derivative3aacted as a selective naked-eye sensor for acetate anions in a mixture of dimethyl sulphoxide and water (9:1 by volume). It interacted with the acetate anions in a 1:2 stoichiometry with strong positive cooperativity and an overall association constant (beta(12)) exceeding 2 x 10(8)M(-2). The detection limit of3atowards the acetate anion was found to be 0.66 x 10(-5)M. The DFT studies showed that both3aand3bwere similar in their electronic properties, but the internal charge transfer for3awas responsible for the positive response to acetate anions.