A new coumarin based dual functional chemosensor for colorimetric detection of Fe3+ and fluorescence turn-on response of Zn2

A new coumarin based Schiff-base dual chemosensor-(E)-2-(((8-hydroxyquinolin-2-yl)methylene)amino)-6H-benzo[c]chromen-one (H10L) was synthesized and evaluated as a colorimetric sensor for Fe3+ and fluorescence turn-on response for Zn2+. Upon treatment with Fe3+ and Zn2+, the absorption intensity as well as the fluorescence emission intensity increases drastically with a distinct color change which provide naked eye detection. However, other common alkali, alkaline earth and transition metal ions failed to induce response or minimal spectral changes. The complex solution of H10L with Zn2+ ion exhibited reversibility with EDTA and regenerate free ligand for further Zn2+ sensing. H10L exhibits two INHIBIT logic gates with two different chemical inputs and the emission as an output. Again, an IMPLICATION logic gate is obtained with Cu2+ and EDTA as chemical inputs and emission as output mode. DFT calculation evaluates the corresponding energy difference between HOMO and LUMO of H10L, Zn-complex and Cu-complex to be 3.67, 1.63 and 2.01eV, respectively. The Cu-complex is found to be more stable than Zn-complex as Cu-complex has higher hardness value than Zn-complex. [Display omitted] •A new coumarin based Schiff-base dual chemosensor has been synthesized and characterized.•H10L was evaluated as a colorimetric sensor for Fe3+ and fluorescence turn-on response for Zn2+.•H10L was able to distinguish Zn2+ from Cd2+ commonly having similar properties.•The stoichiometric ratio evaluated using both BH relation and Job’s plot gives 1:1 stoichiometry.•Free ligand can be regenerated by treating the complex (H10L-Zn2+) with EDTA. A new coumarin based Schiff-base dual chemosensor-(E)-2-(((8-hydroxyquinolin-2-yl)methylene)amino)-6H-benzo[c]chromen-one (H10L) was synthesized and characterized. This chemosensor was evaluated as a colorimetric sensor for Fe3+ and fluorescence turn-on response for Zn2+ among the various survey metal ions. The stoichiometric ratio and association constant were evaluated using Benesi-Hildebrand relation giving 1:1 stoichiometry. This further corroborated 1:1 complex formation based on Job’s plot analyses. The complex solution of H10L with Zn2+ ion exhibited reversibility with EDTA and regenerate free ligand for further Zn2+ sensing. H10L exhibits two INHIBIT logic gates with two different chemical inputs (i) Zn2+ (IN1) and Cu2+ (IN2) and (ii) Zn2+ (IN1) and EDTA (IN2) and the emission as an output. Again, an IMPLICATION logic gate is obtained with