Arvind K. Yadav

Visible-light-mediated difunctionalization of styrenes: an unprecedented approach to 5-aryl-2-imino-1,3-oxathiolanes

The visible-light-induced straightforward synthesis of 5-aryl-2-imino-1,3-oxathiolanes from styrenes and ammonium thiocyanate is reported. The protocol utilizes air (O2) and visible light as green reagents and eosin Y as an organophotoredox catalyst. The reaction involves the formation of C–S bonds followed by intramolecular C–O heterocyclization in a one-pot procedure at room temperature.

Visible-light-mediated eosin Y catalyzed aerobic desulfurization of thioamides into amides

A novel method for the metal-free efficient synthesis of amides from thioamides using visible light and in an air atmosphere in the presence of eosin Y as an organophotoredox catalyst is reported. The protocol involves aerobic desulfurization–oxygenation of thioamides into amides in good to excellent yields at r.t. in a one-pot operation under mild conditions with the formation of nontoxic elemental sulfur as the only by-product. On the basis of several relevant experiments performed, it has been shown that the present photooxidation does not involve a singlet oxygen and accordingly a plausible organocatalytic photoredox mechanism is proposed.

Visible-light-mediated efficient conversion of aldoximes and primary amides into nitriles

A photosensitization-based approach for a convenient and efficient conversion of aldoximes and primary amides into nitriles is reported. The protocol involves eosin Y catalysed, visible-light-mediated in situ formation of the Vilsmeier–Haack reagent from CBr4 and a catalytic amount of DMF, which brings about the desired transformation to afford nitriles at r.t.

An easy access to fluoroalkanes by deoxygenative hydrofluorination of carbonyl compounds via their tosylhydrazones

An efficient and operationally simple synthesis of fluoroalkanes by deoxygenative hydrofluorination of carbonyl compounds via their tosylhydrazone surrogates is reported. The reaction can be carried out in a one-pot procedure directly from carbonyl compounds.

Eosin Y catalyzed difunctionalization of styrenes using O2 and CS2: a direct access to 1,3-oxathiolane-2-thiones

Visible light promoted straightforward highly regioselective synthesis of 1,3-oxathiolane-2-thiones (cyclic dithiocarbonates) starting directly from styrenes, CS2 and air (O2) is reported. The protocol utilizes eosin Y as an organophotoredox catalyst and clean resources like visible light and air (O2) as sustainable reagents at room temperature in a one-pot procedure. Additionally, the approach is advantageous in terms of step economy as it skips the prefunctionalization of styrenes to oxiranes, which has been inevitable in commonly used syntheses of 1,3-oxathiolane-2-thiones.

An easy access to unsymmetrical ureas: a photocatalytic approach to the Lossen rearrangement

An efficient and operationally simple method for the synthesis of unsymmetrical ureas from various hydroxamic acids and amines has been developed. Plausibly, the protocol involves visible-light-initiated in situ formation of Vilsmeier–Haack reagent and COBr2 with CBr4 and a catalytic amount of DMF in the presence of Ru(bpy)3Cl2 as a photocatalyst to bring about the Lossen rearrangement at room temperature.

Metal-Free, One-Pot Oxidative Conversion of Aldehydes to Primary Thioamides in Aqueous Media

Abstract One-pot tandem reactions of a variety of aldehydes with aqueous ammonia, molecular iodine, and O,O-diethyl dithiophosphoric acid readily afford the corresponding primary thioamides. This is an inexpensive, practical, and metal-free way of accessing various thioamides from aldehydes in aqueous media. The pure products are obtained simply by filtration followed by successive washing with aqueous sodium thiosulfate and water. [Supplementary materials are available for this article. Go to the publishers online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] GRAPHICAL ABSTRACT

An unprecedented approach to the Gabriel amine synthesis utilizing tosylhydrazones as alkylating agents

A new and one-pot version of the Gabriel phthalimide amine synthesis utilizing carbonyl compounds as alkylating agents via their tosylhydrazone surrogates is disclosed. The alkylation involves copper catalysed carbene insertion into the N–H bond of phthalimide. Basically, the protocol also offers a powerful tool for deoxygenative hydroamination of carbonyl compounds.