In this report, the highly efficient Rose Bengal-catalysed C(sp)-H selenylation of indoles, imidazoles and arenes was achieved using a half molar equiv. of diorganoyl diselenides. This metal-free, photo-induced protocol resulted in selenylated products in good to excellent yields. The reaction features are high yields, an atom-economic, gram-scalable and metal-free approach, and applicability to different biologically relevant (hetero)arenes.

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Highly efficient molecular-iodine-catalyzed chalcogenations (S and Se) of imidazo[1,2-a]pyridines were achieved by using diorganoyl dichalcogenides under solvent-free conditions. This approach afforded the desired products that had been chalcogenated regioselectively at the C3 position in up to 96 % yield by using DMSO as an oxidant, in the absence of a metal catalyst, and under an inert atmosphere. This mild, green approach allowed the preparation of different types of chalcogenated imidazo[1,2-a]pyridines with structural diversity. Furthermore, the current protocol was also extended to other N-heterocyclic cores.

Herein, we report ag reener iodine-catalyzed protocoltoa ccess different typesofu nsymmetrical diorganyl chalcogenides.T his newa pproach works in the absenceo fs olvent and metal. Thed esired productsw ere obtained in good to excellent yields using one equivalento fa rylboronic acids,h alf an equivalento fv arious diorganyl dichalcogenides, iodine (10 mol%) as ac atalyst and 2equivalents of dimethyls ulfoxide (DMSO;a so xidant), with ar eaction time of 10 min under microwavei rradiation.

Iodine oxidation of bis[2-(hydroxyiminomethyl)phenyl] dichalcogenides yields benzo-1,2-chalcogenazole 2-oxides. Annulated derivatives of iso-tellurazole N-oxides spontaneously aggregate into cyclic tetra- and hexamers through TeO chalcogen bonding; the structures of the co-crystals with benzene and CHCl illustrate the ability of these macrocycles to interact with small guest molecules. The selenium congener crystallizes forming a supramolecular polymer. VT NMR indicates that both compounds aggregate in solution but only at low temperature in the selenium case. The different abilities of these molecules to engage in supramolecular interactions are interpreted on the basis of their electronic properties evaluated with DFT-D3 calculations.

Herein, we report a greener protocol for the synthesis of 3-Se/S-indoles and imidazo[1,2-a]pyridines through direct C(sp )-H bond chalcogenation of heteroarenes with half molar equivalents of different dichalcogenides, using KIO as a non-toxic, easy-to-handle catalyst and a stoichiometric amount of glycerol. The reaction features are high yields, based on atom economy, easy performance on gram-scale, metal- and solvent-free conditions as well as applicability to different types of N-heteroarenes.

We have developed a green and efficient protocol for the chalcogenation of bicyclic arenes by using I2/DMSO as catalytic system under solvent‐ and metal‐free conditions. This protocol allows access to several chalcogenated bicyclic arenes through C(sp2)–H bond functionalization, in good to excellent yields by using microwave irradiation or conventional heating.

Highly efficient KIO 3 -catalyzed chalcogenations (S and Se) of (hetero)arenes, with easily accessible and odorless dichalcogenides, were obtained through direct C(sp 2 )-H bond chalcogenation. Using this benign, atom-economic protocol, the desired products were obtained regioselectively in good to excellent yields in the presence of ethylene glycol (4 equiv.) and KIO 3 (20 mol %) as a non-toxic and easily handled catalyst. This metal-and solvent-free approach is scalable, and it is applicable to different types of (hetero)arenes. Furthermore, several of these chalcogenated (hetero)arenes exhibited a significantly high percentage of AChE inhibition, revealing their potential anti-Alzheimer activity.