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An intermolecular synergistic catalytic combination of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and a DBU-derived bromide ionic liquid has been developed for the conversion of CO₂, epoxides, and amines under metal- and solvent-free conditions. Various 3-aryl-2-oxazolidinones are produced in moderate to excellent yields within a short reaction time. NMR spectroscopy and DFT calculations demonstrate that DBU as a hydrogen bond acceptor and the ionic liquid as a hydrogen bond donor activate the substrates cooperatively by inducing hydrogen bonds to promote the reaction effectively. Based on these results, a possible reaction mechanism on the synergistic catalysis of DBU and the ionic liquid is proposed. In addition, the reaction of CS₂, ethylene oxide, and aniline catalyzed by the combination of DBU and the DBU-derived ionic liquid also proceeds smoothly, which opens a hitherto unreported route to [1,3]dithiolan-2-ylidenephenylamine in a straightforward way.

Simply synergy: The combination of the organic superbase 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and the superbase-derived bromide ionic liquid HDBUBr exhibits intermolecular synergistic catalysis for the reaction of CO₂, epoxides, and amines. Various 3-aryl-2-oxazolidinones are synthesized in moderate to excellent yields. NMR spectroscopy and DFT calculations are used to demonstrate that the synergistic catalysts activate the substrates by inducing hydrogen bonds cooperatively.

Amorphous carbon nitride (ACN) with a bandgap of 1.90 eV shows an order of magnitude higher photocatalytic activity in hydrogen evolution under visible light than partially crystalline graphitic carbon nitride with a bandgap of 2.82 eV. ACN is photocatalytically active under visible light at a wavelength beyond 600 nm.

Chemical doping has been recognized as a promising route to achieve novel physicochemical functions of porous carbons as metal-free catalysts in renewable energy-related technologies, such as electrochemical oxygen reduction reaction (ORR). However, it remains challenging to exploit an effective method for the synthesis of metal-free carbonaceous electrocatalysts. Herein, we report the direct synthesis of phosphorus-doped mesoporous carbonaceous electrocatalysts for the first time through soft-templating method, in which organophosphonic acid serves as the phosphorus source. The resulting mesoporous carbon material possesses high doping level, large surface area, and an interconnected mesopore system, ensuring the sufficient exposure and availability of catalytic sites to realize considerable catalytic activity for ORR in alkaline media. More importantly, much better tolerance for methanol oxidation, higher durability, and comparable Tafel slopes as compared with the commercial Pt/carbon (Pt/C) catalyst are valuable for developing alternative fuel cells and metal–air batteries.

Novel carbon: P-doped metal-free mesostructured carbocatalysts with high surface area are synthesized through a soft-templating strategy with organophosphonic acid as the P source. The catalysts are efficient for the oxygen reduction reaction (ORR) with favorable kinetics, strong durability, and excellent methanol tolerance.