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Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Visible-Light-Switchable Tellurium-Based Chalcogen Bonding: Photocontrolled Anion Binding and Anion Abstraction
Hong-Ying Duan1, Shi-Tao Han1, Tian-Guang Zhan1
1Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, P. R. China.
Abstract:
Exploring new noncovalent bonding motifs with reversibly tunable binding affinity is of fundamental importance in manipulating the properties and functions of supramolecular self-assembly systems and materials. Herein, for the first time, we demonstrate a unique visible-light-switchable telluro-triazole/triazolium-based chalcogen bonding (ChB) system in which the Te moieties are connected by azobenzene cores. The binding strengths between these azo-derived ChB receptors and the halide anions (Cl- , Br- ) could be reversibly regulated upon irradiation by visible light of different wavelengths. The cis-bidentate ChB receptors exhibit enhanced halide anion binding ability compared to the trans-monodentate receptors. In particular, the telluro-triazolium-based ChB receptor can achieve both high and significantly photoswitchable binding affinities for halide anions, which enable it to serve as an efficient photocontrolled organocatalyst for ChB-assisted halide abstraction in a Friedel-Crafts alkylation benchmark reaction.
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