Flash Communication: Intramolecular Chalcogen Bonding as a Driver of Diaryltelluride Oxidation by o-Chloranil

Abstract

Given potential ramifications in catalysis, exploring redox cycling at heavy main group centers is attracting renewed interest. In this context, this study explores how chalcogen bonding interactions can influence the oxidative addition of o-chloranil to the Te(II) center of diaryltellurides. Using a series of diaryltellurides functionalized by ortho-methylene-dimethylamino or -methyl ether functionalities, we show that the formation of a chalcogen bond between the donor atom and the tellurium center drives the oxidation reaction, as confirmed by the isolation and structural characterization of the corresponding Te(IV) monocatecholates. Furthermore, this study also shows that these tetravalent tellurium derivatives react with an additional equivalent of o-chloranil to afford hexachloro-dibenzo[1,4]dioxine-2,3-dione, a known compound, and the corresponding Te(IV) dichlorides. Lastly, this work also documents the facile reductions of the Te(IV) dichlorides into their Te(II) diaryl precursors using dithiothreitol or DTT.