Visible light promoted chemo-selective metal free hydrogenation of activated double bond has been achieved via photoredox catalysis. Eosin Y has proved to an efficient catalyst for the effective reduction of C-C double bonds of isatins, oxindoles and maleimides under visible light. The method worked efficiently without the aid of any external reductants. Commercially viable DIPEA has been employed as a sacrificial electron donor and it’s in-situ generated cationic radical acts as reductant in this transformation. The method proved to be practical as a broad range of substrates containing activated double bond were easily reduced. The method proved to be scalable on a gram scale and the reduced product has been utilized successfully for the further synthetic application. The systematic and detailed mechanistic studies reveal the reductive quenching of the photocatalyst by the activated double bond.
Here we report a
visible-light-promoted metal-free regioselective C3-H trifluoromehtylation
reaction that proceeds via radical mechanism and which supported by control
experiments. The combination of photoredox catalysis and hypervalent iodine
reagent provides a practical approach for the present trifluoromethylation
reaction and synthesis of a library of trifluoromethylated indazoles.
Here, we provide an operationally simple protocol for the highly chemoselective deoxygenation of various functionalized N-heterocyclic N-oxides under visible light-mediated photoredox conditions with Na2-eosin Y as an organophotocatalyst.
A metal-free and visible-light-induced strategy has been established for the construction of α-ketoesters via aerobic oxidation of α-diazoesters with dioxygen in air at room temperature.
The surge of photocatalytic transformation not only provides unprecedented synthetical methods, but also triggers the enthusiasm for more sustainable photocatalysts. On the other hand, oxygen is an ideal oxidant in...
A new visible-light-mediated protocol has been proposed for the synthesis of thiosulfonates via metal-free sulfonylation of thiols with aryldiazonium and sodium metabisulphite at room temperature. This mild three-component reaction, simply...
Metal-free, visible-light-mediated, decarboxylative alkylation of biomass-derived compounds