Photocatalytic Reductive Defluorination of Fluorinated Compounds in Aqueous Alcohol Suspensions of a Metal‐loaded Titanium(IV) Oxide

Use of Biomass Glycerol as a Reducing Agent for Photocatalytic Deprotection of Pyridine N-Oxides in an Aqueous Suspension of Titanium(IV) Oxide

Deprotection of pyridine N-oxides under mild conditions with an inexpensive and environmentally friendly reducing reagent is an important chemical procedure. The use of biomass waste as the reducing reagent, water as the solvent and solar light as the energy source is one of the most promising approaches with minimal impact on the environment. Therefore, a TiO2 photocatalyst and glycerol are suitable components of this type of reaction. Stoichiometric deprotection of pyridine N-oxide (PyNO) with a minimal amount of glycerol (PyNO:glycerol= 7 : 1) was achieved, with only CO2 being produced as the final oxidation product of glycerol. The deprotection of PyNO was thermally accelerated. Under solar light, the temperature of the reaction system increased to 40-50 °C and PyNO was also quantitatively deprotected, indicating that solar energy, i. e., UV light and thermal energy, can be effectively used. The results provide a new approach in the fields of organic chemistry and medical chemistry using biomass waste and solar light.

An S-scheme α-Fe2O3/Cu2O photocatalyst for an enhanced primary amine oxidative coupling reaction under visible light

Photoredox catalysis under visible light has been recorded as a potential and reassuring recipe for organic synthesis. More and more heterojunction catalysts have appeared in people's fields of vision, especially those with S-scheme heterojunction structures. The S-scheme heterojunction structure of a photocatalyst can remarkably improve its photocatalytic efficiency. Here, an S-scheme α-Fe₂O₃/Cu₂O heterojunction photocatalyst was designed and fabricated for the primary amine oxidative coupling reaction. On account of that, the S-scheme structure effectively separated the photogenerated electron-hole pairs and enhanced the photoredox ability of the photocatalytic system. The α-Fe₂O₃/Cu₂O composite could also enhance the reactivity to a large extent. This work will provide new insight into the design of photocatalysts with a more reasonable structure and higher performance.

Recent Advances in Transition-metal-catalyzed C-C Bond Formation via C(sp2 )-F Bond Cleavage

The activation of a carbon-fluorine bond is one of the most challenging topics in modern synthetic organic chemistry due to their low reactivity compared to other carbon-halogen bonds. In this review, we present the recent developments since 2015 on cross-coupling reactions that form C-C bonds via cleavage of C(sp² )-F bonds. Not only the conventional activation of C(sp² )-F bonds, but also decarbonylative or carbonyl-retentive cleavage of C(acyl)-F bonds will be introduced. This paper mainly describes new protocols for the formation of C(sp² )-C(sp³ ), C(sp² )-C(sp² ), and C(sp² )-C(sp) bonds via transition-metal-catalyzed cleavage of C(sp² )-F bonds.