The catalytic resolution of racemic cyclic amines has been achieved by an enantioselective amidation reaction featuring an achiral N-heterocyclic carbene catalyst and a new chiral hydroxamic acid cocatalyst working in concert. The reactions proceed at room temperature, do not generate nonvolatile byproducts, and provide enantioenriched amines by aqueous extraction.
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http://dx.doi.org/10.1021/ja209472h | DOI Listing |
Nat Commun
January 2025
State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, P.R. China.
In this study, we introduce a highly effective non-metallic iodine single-atom catalyst (SAC), referred to as I-NC, which is strategically confined within a nitrogen-doped carbon (NC) scaffold. This configuration features a distinctive C-I coordination that optimizes the electronic structure of the nitrogen-adjacent carbon sites. As a result, this arrangement enhances electron transfer from peroxymonosulfate (PMS) to the active sites, particularly the electron-deficient carbon.
View Article and Find Full Text PDFACS Nano
January 2025
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University, Jinan 250061, P. R. China.
To achieve a long cycle life and high-capacity performance for Li-O batteries, it is critical to rationally modulate the formation and decomposition pathway of the discharge product LiO. Herein, we designed a highly efficient catalyst containing dual catalytic active sites of Pt single atoms (Pt) paired with high-entropy alloy (HEA) nanoparticles for oxygen reduction reaction (ORR) in Li-O batteries. HEA is designed with a moderate d-band center to enhance the surface adsorbed LiO intermediate (LiO(ads)), while Pt active sites exhibit weak adsorption energy and promote the soluble LiO pathway (LiO(sol)).
View Article and Find Full Text PDFEnzyme Microb Technol
January 2025
Protein Chemistry and Enzyme Technology, Department of Biotechnology and Biomedicine, Building 221, Technical University of Denmark, Lyngby DK-2800 Kgs, Denmark. Electronic address:
Aspergillus spp. and Rhizopus spp., used in solid-state plant food fermentations, encode cobalamin-independent methionine synthase activity (MetE, EC 2.
View Article and Find Full Text PDFMetal oxides are promising catalysts for small molecule hydrogen chemistries, mediated by interfacial proton-coupled electron transfer (PCET) processes. Engineering the mechanism of PCET has been shown to control the selectivity of reduced products, providing an additional route for improving reductive catalysis with metal oxides. In this work, we present kinetic resolution of the rate determining proton-transfer step of PCET to a titanium-doped POV, TiVO(OCH) with 9,10-dihydrophenazine by monitoring the loss of the cationic radical intermediate using stopped-flow analysis.
View Article and Find Full Text PDFChem Sci
January 2025
Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong Wollongong New South Wales 2522 Australia
Although electrostatic catalysis can enhance the kinetics and selectivity of reactions to produce greener synthetic processes, the highly directional nature of electrostatic interactions has limited widespread application. In this study, the influence of oriented electric fields (OEF) on radical addition and atom abstraction reactions are systematically explored with ion-trap mass spectrometry using structurally diverse distonic radical ions that maintain spatially separated charge and radical moieties. When installed on rigid molecular scaffolds, charged functional groups lock the magnitude and orientation of the internal electric field with respect to the radical site, creating an OEF which tunes the reactivity across the set of gas-phase carbon-centred radical reactions.
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