A catalytic asymmetric double (1,3)-dipolar cycloaddition reaction has been developed. Using a chiral silver catalyst, enantioenriched pyrrolizidines can be prepared in one flask from inexpensive, commercially available starting materials. The pyrrolizidine products contain a variety of substitution patterns and as many as six stereogenic centers.
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http://dx.doi.org/10.1039/C2SC21617E | DOI Listing |
JACS Au
January 2025
Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay, Guangzhou University, Guangzhou 510006, China.
Slow mass transfer processes between inert emerging contaminants (ECs) and dissolved oxygen (DO) limit natural water self-purification; thus, excessive energy consumption is necessary to achieve ECs removal, which has become a longstanding global challenge. Here, we propose an innovative water self-purification expansion strategy by constructing asymmetric surfaces that could modulate trace HO as trigger rather than oxidant to bridge a channel between inert ECs and natural dissolved oxygen, achieved through a dual-reaction-center (DRC) catalyst consisting of Cu/Co lattice-substituted ZnO nanorods (CCZO-NRs). During water purification, the bond lengths of emerging contaminants (ECs) adsorbed on the asymmetric surface were stretched, and this stretching was further enhanced by HO mediation, resulting in a significant reduction of bond-breaking energy barriers.
View Article and Find Full Text PDFRSC Adv
January 2025
Shaanxi Province Key Laboratory of Catalytic, School of Chemical and Environmental Science, Shaanxi University of Technology Hanzhong 723001 P. R. China
Asymmetric catalytic reactions are essential for synthesizing chiral drugs and fine chemicals, with their stereoselectivity influenced significantly by interactions between catalysts and substrates. Ketone catalysts have garnered considerable attention in the realm of asymmetric photoreactions because of their highly controllable structures, ease of availability, and environmental friendliness. This review highlights the application of various reported ketone catalysts in a range of asymmetric photoreactions, including [2 + 2] photocycloaddition, photoderacemization, photochemical rearrangement, asymmetric electrophilic amination, and asymmetric alkylation of aldehydes.
View Article and Find Full Text PDFNat Commun
January 2025
School of Mechatronical Engineering, Beijing Institute of Technology, Beijing, 100081, China.
Designing asymmetrical structures is an effective strategy to optimize metallic catalysts for electrochemical carbon dioxide reduction reactions. Herein, we demonstrate a transient pulsed discharge method for instantaneously constructing graphene-aerogel supports asymmetric copper nanocluster catalysts. This process induces the convergence of copper atoms decomposed by copper chloride onto graphene originating from the intense current pulse and high temperature.
View Article and Find Full Text PDFNat Commun
January 2025
Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai, P. R. China.
Metal-centered chirality has been recognized for over one century, and stereogenic-at-metal complexes where chirality is exclusively attributed to the metal center due to the specific coordination pattern of achiral ligands around the metal ion, has been broadly utilized in diverse areas of natural science. However, synthesis of these molecules remains constrained. Notably, while asymmetric catalysis has played a crucial role in the production of optically active organic molecules, its application to stereogenic-at-metal complexes is less straightforward.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Transition-metal-catalyzed enantioselective C-H activation has transformed the landscape of asymmetric synthesis, enabling the efficient conversion of C-H bonds into C-C and carbon-heteroatom (C-X) bonds. However, the formation of C-S bonds through enantioselective C-H thiolation remains underdeveloped due to challenges such as catalyst deactivation and competitive coordination of sulfur-containing compounds with chiral ligands. Herein, we report an unprecedented approach to constructing sulfur-substituted planar chiral ferrocenes (PCFs) through copper-mediated enantioselective C-H thiolation enabled by only a 2.
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