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The electrocatalytic reduction of NO 2 - (NO 2 RR) holds promise as a sustainable pathway to both promoting the development of emerging NH 3 economies and allowing the closing of the NO x loop. Highly efficient electrocatalysts that could facilitate this complex six-electron transfer process are urgently desired. Herein, tremella-like CoNi-LDH intercalated by cyclic polyoxometalate (POM) anion P 8 W 48 (P 8 W 48 /CoNi-LDH) prepared by a simple two-step hydrothermal-exfoliation assembly method is proposed as an effective electrocatalyst for NO 2 - to NH 3 conversion. The introduction of POM with excellent redox ability tremendously increased the electrocatalytic performance of CoNi-LDH in the NO 2 RR process, causing P 8 W 48 /CoNi-LDH to exhibit large NH 3 yield of 0.369 mmol h -1 mg cat -1 and exceptionally high Faradic efficiency of 97.0% at -1.3 V vs the Ag/AgCl reference electrode in 0.1 M phosphate buffer saline (PBS, pH = 7) containing 0.1 M NO 2 - . Furthermore, P 8 W 48 /CoNi-LDH demonstrated excellent durability during cyclic electrolysis. This work provides a new reference for the application of POM-based nanocomposites in the electrochemical reduction of NO 2 - to obtain value-added NH 3 .

Fatty acids (FAs) are transported by serum albumin in plasma. Studies have been undertaken to address the binding of MCFAs or LCFAs to human plasma albumin (HPA) and bovine serum albumin (BSA) by characterizing the binding affinities. Previous research on FA binding to serum albumin was usually performed in dilute solutions that are not sufficiently concentrated for the interpretation of the significance of the results under normal physiological conditions. How macromolecular crowded media affect fatty acids and bovine serum albumin (BSA) binding remains unknown. In this article, we investigated the mechanism of FA-BSA binding in a polyethylene glycol crowding environment by using thermodynamic and spectroscopic methods. Molecular crowding increased the binding constant for saturated medium-chain fatty acids (MCFAs) but significantly decreased the binding constant for unsaturated long-chain FAs. The binding sites tended to increase in all the cases. Further investigation revealed that crowding media might loosen the structure of BSA, facilitating MCFA-BSA binding. This research is useful for understanding the transportation of FAs by BSA under physiological conditions and may also help to control digestion by the eventual incorporation of macromolecular crowding agents into food formulations.

Highly diastereoselective and enantioselective desymmetrization of α-substituted cyclohexadienones via NHC-catalyzed intramolecular Stetter reaction was realized. Amino-indanol derived triazolium salt bearing a C(6)F(5) group was found to be the optimal catalyst precursor in the intramolecular Stetter reaction furnishing tricyclic products bearing multi-stereocenters in up to 96% yield and >99% ee.

Enantioselective N-heterocyclic carbene-catalyzed Michael addition reactions to α,β-unsaturated aldehydes by redox oxidation were realized. With 10 mol % of camphor-derived triazolium salt D, 15 mol % of DBU, 5 mol % of NaBF(4), and 100 mol % of quinone oxidant, the reactions of various dicarbonyl compounds with α,β-unsaturated aldehydes led to 3,4-dihydro-α-pyrones in good yields and excellent ee's., (© 2011 American Chemical Society)