AbstractA novel, metal-free cross-dehydrogenative coupling (CDC) reaction of C(sp2)–H bonds of enamines and α-oxo ketene dithioacetals with C(sp3)–H bonds of 1,3-diarylpropenes mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) is reported. The α-alkylation products are obtained with moderate to good yields. The method provides an efficient and alternative strategy for the synthesis of the corresponding products.

The advantage of visible-light photocatalysis lies in its use of clean, renewable, cheap visible light as a driving force. Recently heterogeneous visible light photocatalysts have drawn much attention due to their nature of easy recycling and simple chemical work-up. Immense effort has been devoted to the application of solar energy in the field of energy regeneration such as hydrogen production and the reduction of carbon dioxide. Recently, solar energy has also captured much attention in organic synthesis due to its unique advantages. This paper will review the state-of-the-art progresses in the application of heterogeneous visible-light photocatalysis in organic synthesis through four sections: oxidation of alcohols, oxidation of amines, carbon–carbon bond formation reactions, and carbon–hetero bond formation reactions.

The regioselective addition of α-aminoalkyl radicals to 2,3-allenoates by visible-light-mediated electron transfer using 1 mol% of Ru(bpy)3(BF4)2 as a photocatalyst was successfully established. This photoredox protocol is a simple and effective method for the synthesis of unsaturated γ-aminobutyric ester derivatives.

Mediated by visible light-induced photoredox catalysis and free of other catalysts, a new and efficient synthesis of methylene-bridged bis-1,3-dicarbonyl derivatives has been developed. A variety of N-methyl tertiaryamines and 1,3-dicarbonyl compounds were investigated in this reaction.Under catalyst free conditions in aqueous media, methylene-bridged bis-1,3-dicarbonyl derivatives were successfully prepared by a novel and efficient method using visible-light photocatalytic oxidation of N-methyl tertiaryamines.

Catalyzed by Ru(bpy)3(BF4)2, the photoredox coupling of tertiary amines with acrylate derivatives including Baylis–Hillman adducts under visible light irradiation was successfully established. The scope of the substrates was broad, and thus an array of γ-aminobutyric ester derivatives was obtained in moderate to good yields.

Promoted by diethyl azodicarboxylate, a novel and highly stereoselective synthesis of cis-β-enaminones via oxidative dehydrogenation and hydration of the substituted propargylamines was realized. The possible mechanism was also proposed.

The advantage of visible-light photocatalysis lies in its use of clean, renewable, cheap visible light as a driving force. Recently heterogeneous visible light photocatalysts have drawn much attention due to their nature of easy recycling and simple chemical work-up. Immense effort has been devoted to the application of solar energy in the field of energy regeneration such as hydrogen production and the reduction of carbon dioxide. Recently, solar energy has also captured much attention in organic synthesis due to its unique advantages. This paper will review the state-of-the-art progresses in the application of heterogeneous visible-light photocatalysis in organic synthesis through four sections: oxidation of alcohols, oxidation of amines, carbon–carbon bond formation reactions, and carbon–hetero bond formation reactions.

Promoted by diethyl azodicarboxylate, a novel and highly stereoselective synthesis of cis-β-enaminones via oxidative dehydrogenation and hydration of the substituted propargylamines was realized. The possible mechanism was also proposed.