Ratiometric fluorescent scaffold giving discrete response towards iodide ion: a combined experimental and DFT study

Two donor–acceptor (D–A) type Zn(ii) complexes as fluorescent probes for highly selective detection of iodide

Two noval donor-acceptor (D–A) type Zn(ii) complexes ([Zn₂(L¹)₂(MeCN)(MeOH)]·(MeCN) (1) and [ZnL²(H₂O)] (2)) were obtained and selectively detected iodide as fluorescent probes.

Theoretical investigation on the interaction of benzazaborole derivatives with iodide ion: Structural, binding and fluorescence properties analysis

The structural, fluorescence properties and binding interaction of benzazaborole derivatives 1-hydroxy-2-(α-methyl) benzyl-1,2-benzo boron nitrogen heterocyclic-3-phosphate diethyl ester (PADE) and 1-hydroxy-2-(2-chloro) benzyl-1,2-benzo boron nitrogen heterocyclic-3-phosphate diethyl ester (PADC) with iodide ion have been investigated utilizing density functional theory (DFT) and Time-dependent density functional theory (TD-DFT) method, in which the PADE and PADC showed strong emission in aqueous solution and fluorescence quenching was observed upon addition of iodide ion. The theoretical study indicates that the strong hydrogen-bond (O-H…I) between benzazaborole derivatives and iodide ion leads to the formation of the benzazaborole-iodide ion complexes. The excited state properties have been explored by theoretical calculation to understand the fluorescent quenching upon introduction of iodide ion. The strong fluorescent emission is originated by the electron transfer from benzyl and phosphate moieties to benzo boron nitrogen fused heterocycle moiety, while the fluorescence quenching is attributed to the electron transfer between the PADE (PADC) and iodide ion. The density difference (EDD) maps and the frontier molecular orbitals diagrams during excitation and de-excitation process demonstrate that the photoinduced electron transfer process between PADE (PADC) and iodide ion leads to fluorescence quenching after a significant internal conversion.

Novel fluorescent chemosensing of CN− anions with nanomolar detection using the Zn2+–isonicotinohydrazide metal complex

A novel chemosensor based on the Zn²⁺–isonicotinohydrazide complex ‘(ZnL)’ was developed for the selective detection of cyanide (CN⁻) over other tested anions, such as HSO₄⁻, F⁻, Cl⁻, Br⁻, I⁻, NO₃⁻, PO₄³⁻, SO₄²⁻, SCN⁻, S²⁻, CH₃COO⁻ and H₂PO₄⁻ in 100% aqueous medium.