Electrochemical synthesis of selenyl-dihydrofurans via anodic selenofunctionalization of allyl-naphthol/phenol derivatives and their anti-Alzheimer activity.

Herein, we report an eco-friendly, electrosynthetic approach for the intramolecular oxyselenylation of allyl-naphthol/phenol derivatives. This reaction proceeds with 0.2 equiv. of nBu4NClO4 as an electrolyte and Pt working electrodes in an undivided cell, resulting in the selenyl-dihydrofurans in good to excellent yields. Furthermore, several of the synthesized products presented a high percentage of acetylcholinesterase (AChE) inhibition, highlighting their potential anti-Alzheimer activity.

Photoinduced, Direct C(sp2 )-H Bond Azo Coupling of Imidazoheteroarenes and Imidazoanilines with Aryl Diazonium Salts Catalyzed by Eosin†Y.

Herein, a greener approach to the eosin Y-Na2 catalyzed, C(sp2 )-H bond azo coupling of imidazoheteroarene with aryl diazonium salts is described, under acid free conditions. This direct photoredox process resulted in the corresponding azo products in good to excellent yields. Besides, this new approach could also be applicable to anilines, which is a poorly reactive substrate by other methods. The main features of this reaction are that it provides high yields and is gram-scalable and applicable to biologically relevant imidazoheteroarenes and -anilines.

Rose Bengal catalysed photo-induced selenylation of indoles, imidazoles and arenes: a metal free approach.

In this report, the highly efficient Rose Bengal-catalysed C(sp2)-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.

Direct, Metal-free C(sp2 )-H Chalcogenation of Indoles and Imidazopyridines with Dichalcogenides Catalysed by KIO3.

Herein, we report a greener protocol for the synthesis of 3-Se/S-indoles and imidazo[1,2-a]pyridines through direct C(sp2 )-H bond chalcogenation of heteroarenes with half molar equivalents of different dichalcogenides, using KIO3 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.

Metal- and Solvent-Free Approach to Access 3-Se/S-Chromones from the Cyclization of Enaminones in the Presence of Dichalcogenides Catalyzed by KIO3.

Herein, we describe a greener protocol for the one-pot synthesis of 3-Se/S-4H-chromen-4-ones. The desired products were obtained in good to excellent yields using 2-hydroxyphenyl enaminones and half equivalents of various odorless diorganyl dichalcogenides (S/Se) in the presence of glycerol (5 molar equiv) and KIO3 (15 mol %) as the catalyst under solvent-free conditions.