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Updated: Nov 1, 2025

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Chalcogen-Bonding Catalysis with Telluronium Cations
Robin Weiss1, Emmanuel Aubert2, Patrick Pale1
1LASYROC, UMR 7177, University of Strasbourg, 1 Rue Blaise Pascal, 67000, Strasbourg, France.
Abstract:
Chalcogen bonding results from non-covalent interactions occurring between electrodeficient chalcogen atoms and Lewis bases. Among the chalcogens, tellurium is the strongest Lewis acid, but Te-based compounds are scarcely used as organocatalysts. For the first time, telluronium cations demonstrated impressive catalytic properties at low loadings in three benchmark reactions: the Friedel-Crafts bromination of anisole, the bromolactonization of ω-unsaturated carboxylic acids and the aza-Diels-Alder between Danishefsky's diene and imines. The ability of telluronium cations to interact with a Lewis base through chalcogen bonding was demonstrated on the basis of multi-nuclear (17 O, 31 P, and 125 Te) NMR analysis and DFT calculations.
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