Benzil-tethered precipitons for controlling solubility: a round-trip energy-transfer mechanism in the isomerization of extended stilbene analogues

Visible Light-Emitting Diode Light-Driven Cu0.9Fe0.1@RCAC-Catalyzed Highly Selective Aerobic Oxidation of Alcohols and Oxidative Azo-Coupling of Anilines: Tandem One Pot Oxidation-Condensation to Imidazoles and Imines

Here, we have demonstrated visible light-emitting diode light-driven selective and efficient aerobic oxidation of primary/secondary alcohols to aldehydes/ketones and oxidative azo-coupling of anilines using biomass rice husk-derived chemically activated carbon sheet-supported copper-iron bimetallic hybrid nanomaterials (Cu _x Fe_1-x @RCAC) under oxidant and additive-free conditions. The catalytic activity of the Cu _x Fe_1-x @RCAC materials has been investigated for the oxidation of alcohols and anilines, and Cu_0.9Fe_0.1@RCAC was established as the best catalyst. Moreover, a tandem one-pot protocol has been developed for the sequential oxidation of alcohols followed by condensation to functionalized imidazole and imine derivatives in high isolated yields. The hybrid materials were highly robust and stable under the reaction conditions and were recovered simply by filtration and recycled up to 12th run without considerable loss in catalytic activity.

Photocatalytic regeneration of brominating agent in the visible light-mediated synthesis of imidazo[1,2-a]pyridines

Regenerating the brominating agent by erythrosine B closes a catalytic cycle for the construction of the imidazo[1,2-a]pyridine framework.

Organic Dye-Catalyzed, Visible-Light Photoredox Bromination of Arenes and Heteroarenes Using N-Bromosuccinimide

A variety of arenes and heteroarenes are brominated in good to excellent yields using N-bromosuccinimide (NBS) under mild and practical conditions. According to mechanistic investigations described within, the reaction is speculated to proceed via activation of NBS through a visible-light photoredox pathway utilizing erythrosine B as a photocatalyst. A photo-oxidative approach effectively amplifies the positive polarization on the bromine atom of the NBS reagent. This increase in the electrophilic nature of NBS results in drastically reduced reaction times and diversion from competing light-promoted reactive pathways.

Blue-light-promoted carbon-carbon double bond isomerization and its application in the syntheses of quinolines

A blue-light-promoted carbon-carbon double bond isomerization in the absence of any photoredox catalyst is reported. It provides rapid access to a series of quinolines in good to excellent yields under simple aerobic conditions. The protocol is direct, catalyst-free and operationally convenient.

Synthesis of smart bimetallic nano-Cu/Ag@SiO2for clean oxidation of alcohols

Silica (SiO₂) supported bimetallic copper/silver nanoparticles (Cu/Ag@SiO₂NPs) were synthesized for clean oxidation of benzoins/benzyl alcohols. All the reactions were fast, clean and high yielding (95–99%) and the Cu/Ag@SiO₂nano-catalyst was reused eight times without loss of its catalytic performance.

One-pot, two-step desymmetrization of symmetrical benzils catalyzed by the methylsulfinyl (dimsyl) anion

Symmetrical-to-unsymmetrical benzil conversion is realized by a one-pot two-step procedure involving a chemoselective cross-benzoin reaction followed by microwave-assisted oxidation of the benzoylated benzoin intermediate.