A chiral composite material, derived from the deposition of a chiral nickel-diamine complex via wet impregnation to MCM-41, was shown to be an efficient heterogeneous catalyst for asymmetric 1,4-addition reactions of 1,3-dicarbonyl compounds with nitroalkenes, and of nitromethane with alkylidenemalonates. It was discovered that MCM-41 enhanced the reactivity and improved the stability of the chiral nickel complex that resides within the mesoporous material.
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http://dx.doi.org/10.1002/anie.201906349 | DOI Listing |
Nat Commun
January 2025
Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, Chemical Biology Research Center, School of Pharmaceutical Sciences, Chongqing University, Chongqing, China.
Helicene-shaped molecules are compelling chemical structures with unique twisted helical chirality and remarkable properties. Although progress occurs in the catalytic asymmetric synthesis of helicene (-like) molecules, the enantioselective synthesis of multiple helicenes, especially four or higher helicity, is still challenging and has yet to be achieved. Herein, we report an organocatalytic [4 + 2] cycloadditions to achieve double S-shaped quadruple helicene-like molecules with high enantioselectivity (up to 96% e.
View Article and Find Full Text PDFACS Nano
January 2025
Key Laboratory of Photoelectronic Conversion and Utilization of Solar Energy, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 260101, China.
Engineering the local coordination environment of single metal atoms is an effective strategy to improve their catalytic activity, selectivity, and stability. In this study, we develop an asymmetric Pd-Ag diatomic site on the surface of g-CN for the selective electrocatalytic semihydrogenation of alkynes. The single Pd atom catalyst, which has a locally symmetric Pd coordination, was inactive for the semihydrogenation of phenylacetylene in a 1 M KOH and 1,4-dioxane solution at an applied potential of -1.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Tsinghua University, Department of Chemistry, 1 Tsinghua Yuan, 100084, Beijing, CHINA.
Enantioselective hydrogenation of tetrasubstituted alkenes to form 1,2-contiguous stereocenters is a particularly appealing but highly challenging transformation in asymmetric catalysis. Despite the notable progress achieved in enantioselective hydrogenation over the past decades, enantioselective hydrogenation of all-carbon tetrasubstituted alkenes containing multiple alkyl groups remains an unsolved challenge. Here, we report a rhodium-catalyzed highly diastereo- and enantioselective hydrogenation of diverse acyclic multisubstituted alkenes under mild conditions.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Science and Technology of China, National Synchrotron Radiation Laboratory, 42#, South Road of HeZuoHua, 230029, Hefei, CHINA.
Fe-N-C catalysts, with a planar D4h symmetric FeN4 structure, show promising as noble metal-free oxygen reduction reaction catalysts. Nonetheless, the highly symmetric structure restricts the effective manipulation of its geometric and electronic structures, impeding further enhancements in oxygen reduction reaction performance. Here, a high proportion of asymmetric edge-carbon was successfully introduced into Fe-N-C catalysts through morphology engineering, enabling the precise modulation of the FeN4 active site.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
College of Chemistry, Central China Normal University, Wuhan 430079, Hubei, China.
With the rapid advancements in asymmetric catalysis, there is a growing need for the asymmetric selective synthesis of complex and diverse molecules with chiral axes. Axially chiral molecules are not only present in natural products and drugs but also in specialized chiral ligands and catalysts. The catalytic asymmetric synthesis of axially chiral molecules has garnered significant attention within the chemical community.
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