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The polymerization of α-olefins catalyzed by zirconium metallocene catalyst was systematically studied through experiments and density functional theory (DFT) calculations. Having achieved an agreement between theory and experiment, it was found that the effect of the catalyst ligand on the C[double bond, length as m-dash]C insertion reaction was significantly greater than that on the β-H elimination reaction. Therefore, the molecular weight of polymers can be increased by improving the activity of the C[double bond, length as m-dash]C insertion. In addition, in comparison with propylene, the chain length of α-olefins can directly affect the stereotacticity of polymerization products, owing to steric hindrance between the polymer chain and monomer.
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http://dx.doi.org/10.1039/d2ra03180a | DOI Listing |
Nat Commun
August 2025
State Key Laboratory of Heavy Oil Processing, Key Laboratory of Optical Detection Technology for Oil and Gas, China University of Petroleum, Beijing, China.
Simultaneous oxidation of soot and CH emitted from natural gas-diesel dual fuel engine is a new challenge. Herein, a robust catalyst of binary Ru-Pd components supported on three-dimensional ordered macro-mesoporous cerium-zirconium oxide (RuPd/3DOMM-CZO) is elaborately constructed. Ordered macro-mesopore structure in novel hierarchical porous cerium-zirconium oxide can respectively enhance mass transfer of soot and gaseous reactants, and binary Ru-Pd active components can improve activation for NO and CH.
View Article and Find Full Text PDFACS Catal
May 2025
Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, United States.
The direct catalytic reductive amination of amides remains a challenging transformation, particularly when using weakly nucleophilic amines. However, this strategy offers several synthetic advantages, particularly due to the wide availability of amides, as well as -sulfonyl and -sulfinyl amines. We present a mild catalytic approach for the monoalkylation of sulfonamides, sulfamates, sulfamides, and sulfinamides using amides.
View Article and Find Full Text PDFMikrochim Acta
July 2025
School of Food Science and Engineering, Yangzhou University, Yangzhou, 225127, Jiangsu, China.
Staphylococcus aureus, a prevalent foodborne pathogenic bacterium, poses a significant threat to human health. Herein, a dual-mode sensing method is proposed for detecting S. aureus in food using aptamer-modified Fe/Zr metal organic framework (Apt@Fe/Zr MOF).
View Article and Find Full Text PDFACS Mater Au
July 2025
Department of Chemistry, University of Basel, Mattenstrasse 22, 4058 Basel, Switzerland.
Kinetic control is a powerful tool for traversing the chemical landscape toward the intended product. For group 4 metal oxide nanocrystals, the development of complex multimetallic heterostructures is still a challenge, partly due to the lack of kinetic and mechanistic understanding. Here, we study the reaction kinetics of the nonaqueous synthesis of titanium, zirconium, and hafnium oxide nanocrystals, from the decomposition of metal isopropoxide and metal halide, in the presence of tri--octylphosphine oxide (TOPO).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
August 2025
Department of Applied Chemistry, Graduate School of Engineering, The University of Osaka, Suita, Osaka, Japan.
Decarboxylative hydrazination of carboxylic acids was achieved using a 1:5:2 ratio of three metal salts, Ce(OBu), Zr(OBu), and Mn(OAc), as a catalyst under visible light irradiation. The catalytic activity, compared with our previously developed Ce cluster photo-catalysts, was enhanced by the formation of single cerium-incorporated hexanuclear mixed-metal clusters containing a [CeZrO(OH)] core. The manganese salts further accelerated the overall reaction rate (10 times faster reaction rate with the manganese salt than that of the manganese-free conditions).
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