A Benzothiadiazole‐Based Thiourea Receptor for Selective Chloride Extraction and Reversible Fluoride Sensing
Year: 2025
Type: article
Abstract: In supramolecular chemistry, thiourea binding sites have gained paramount attention due to their ability to bind anions employing directional hydrogen bonding (HB) interactions. In this work, we report a new thiourea‐based anion receptor, BDTU, incorporating electron‐deficient benzothiadiazole (BTD) as a signaling unit. The binding affinity and signaling ability of BDTU toward various anions of different geometry and basicity are investigated by 1 H NMR, UV–vis, and fluorescence techniques in CH 3 CN. As determined by NMR spectroscopic analyses, BDTU shows moderate selectivity toward chloride (Cl − ) over other halides and oxyanions, forming relatively stable 1:2 host–guest stoichiometric complex that is stabilized by thiourea NH HBs. In this regard, the single crystal X‐ray structure of the Cl − complex of BDTU has revealed short and directional intermolecular N─H⋯Cl − HB with chloride. Importantly, this strong HB with Cl − is successfully utilized in the solid‐liquid extraction of chloride. Furthermore, the photophysical studies reveal a reversible anion sensing behavior of BDTU toward fluoride (F − ) in CH 3 CN. Thus, BDTU is demonstrated for dual applications in extraction as well as sensing of anions.
Source: Chemistry - An Asian Journal
DOI: 10.1002/asia.70183
Authors: Iti Ghosh, Sourav Pramanik, Abu S. M. Islam, Abhishek Dutta, Pradyut Ghosh
Institution: Indian Association for the Cultivation of Science
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4413094809