Development of Novel Hypervalent Iodine Compounds Bearing Intramolecular Halogen Bonding

In recent years, halogen bonding (XB) interaction has attracted much attention in organic synthesis, especially for the activation of substrates. On the other hand, the use of XB interaction for the “stabilization” of molecules has been less explored. In this manuscript, the authors described our recent work on the development of new class of N-acyliminoiodinanes and iodonium ylides, which can be used as nitrene and carbene equivalents, respectively. The intramolecular XB interactions were confirmed by X-ray structure and natural bond orbital (NBO) analyses. The synthesized N-acyliminoiodinanes were found to be activated by photo-irradiation to react with silyl enol ethers, glycals, alkynes, and(hetero)aromatic compounds to afford the corresponding aminated adducts. In addition, the iodonium ylides baring intramolecular XB interaction underwent additive-free chemoselective coupling reaction of thioamides, even in protic polar solvents. The intramolecular XB could also control the coordination mode of the nucleophile via σ-holes, suppressing undesired side reactions. These findings would pave new avenues chemoselective coupling reactions using hypervalent iodine compounds.