Interplay between the intramolecular hydrogen bonds and cation–π interactions in various complexes of salicylaldehyde, thiosalicylaldehyde and selenosalicylaldehyde with Li+, Na+, K+, Mg2+ and Ca2+ cations

Design and synthesis of a new tripod-chromogenic sensor based on a s-triazine and thiazolidine-2,4-dione ring (TCST) for naked-eye detection of Li+

A novel tripod-chromogenic sensor based on a s-triazine and thiazolidine-2,4-dione ring (TCST) was designed, synthesized, and applied as a colorimetric probe in aqueous solutions of dimethyl sulfoxide (DMSO). The probe showed a highly sensitive and selective colorimetric sensor for naked-eye detection of Li+, changing from colourless to yellow. The probe’s detection limit toward Li+ was found to be 1.2 μM. The result of the Job plot analysis showed 1:1 stoichiometry for the interaction between the tripod chemosensor and Li+ and this result was confirmed by 1H NMR titration experiments. The probe can also be used for biological activities depending on the results of microbial tests.