Benzo‐γ‐pyrone‐based diorganotin (IV) chelates as fluorescent probes for the detection of picric acid from soil and aqueous samples

Abstract

Four chelates of diorganotin (IV) from benzo-γ-pyrone ligands have been derived and their structural features are investigated. Benzo-γ-pyrone ligands (L 1 -L 2 ) behave as bidentate chelating agents and form [L 2 SnR 2 ] type of chelates (1-4; where L = ligand, R = C 4 H 9 , CH 3 ) with "skew-trapezoidal bipyramidal" arrangement. The fluorescent nature, electron-rich sites, and photostability of the test diorganotin (IV) chelate 1 make it a suitable probe for the recognition of picric acid (PA). The optimized analytical protocol demonstrates the detection limit of 45.19 nM of PA with a linear range of 0.49-12.66 μM and a quick response time of 10 s. Moreover, soil and aqueous sample analysis along with fabrication of SiO 2 @Al strips for the visual response display the real-time application of the synthesized chelate. The high recovery rate of 92.5% to 100.4% with significant precision of 0.36%-3.63% in real samples makes the probe a good chemosensor for the PA. Further stability of the synthesized compounds in water explored the tendency of the probe to detect PA in real aqueous samples.