Article
Energy & Fuels
Xiaoye Wang, Xiangxin Han, Yulong You, Xiumin Jiang
Summary: Solid-state nuclear magnetic resonance (SSNMR) techniques were used to characterize Dachengzi oil shale kerogen, revealing that protonated aromatic signals account for 24% of total aromatic signals and oxygen atoms play a crucial role in connectivities between different groups. Additionally, the presence of long methylene chain structures was indicated in the study.
Review
Chemistry, Physical
Joanna Szymczak, Michal Kryjewski
Summary: The review highlights the use of heterogenic catalysts based on porphyrins and phthalocyanines loaded on mesoporous materials for oxidation reactions, with a focus on alkane, alkene, and arene substrates. Mesoporous silica is a promising candidate for anchoring macrocycles and obtaining new catalysts. The catalytic reactions studied are primarily aimed at producing epoxides, alcohols, ketones, aldehydes, or acids, with a particular interest in the oxidation of cyclohexane and cyclohexene. Some reactions exhibit biomimetic processes resembling those catalyzed by the cytochrome P450 enzyme family.
Article
Environmental Sciences
Jingzhao Wang, Chao Ren, Zhen Li, Wei Li
Summary: The interaction between phosphate and soil minerals is crucial for understanding phosphorus cycling in natural and agricultural systems. This study utilized solid-state NMR spectroscopy to investigate the kinetics of phosphate uptake onto calcite. The results showed the formation of amorphous calcium phosphate (ACP) initially, which transformed into carbonated hydroxyapatite (CHAP) over time for both low and high phosphate concentrations.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Chemistry, Physical
Takeshi Kobayashi, Marek Pruski
Summary: Recent studies have shown the potential of using dynamic nuclear polarization (DNP) to detect O-17 solid-state NMR spectra of naturally abundant samples within a reasonable experimental time. This study successfully demonstrated the detection of signals from non-protonated O-17 in materials containing silicon, utilizing a Si-29-detected scheme to achieve 2D O-17-Si-29 heteronuclear correlation spectroscopy in mesoporous silica and silica-alumina surfaces at natural abundance. The sensitivity boost in this experiment came from indirect DNP excitation of Si-29 via protons, indirect detection of O-17 through Si-29 nuclei using two-dimensional Si-29{O-17} D-HMQC, and Carr-Purcell-Meiboom-Gill refocusing of Si-29 magnetization during acquisition.
Article
Chemistry, Inorganic & Nuclear
Alexandros Mortis, Cacilia Maichle-Mossmer, Reiner Anwander
Summary: A series of new yttrium donor adduct complexes were successfully synthesized and fully characterized, with two chosen for surface organometallic chemistry research. Mesoporous nanoparticles were used as a support material, with various characterization techniques employed to analyze the parent and hybrid materials, showing that surface silylation promoted by HN(SiHMe2)(2) is superior to titration with lithium alkyl LiCH2SiMe3.
DALTON TRANSACTIONS
(2022)
Article
Nanoscience & Nanotechnology
Neil Robinson, Eric F. May, Michael L. Johns
Summary: Solid-fluid interactions are crucial for porous materials in various chemical processes, but the opaque nature of these systems hinders detailed characterization of interfacial phenomena. A low-magnetic-field two-dimensional H-1 nuclear spin relaxation measurement provides insights into adsorbate identity and interfacial dynamics, showcasing distinct relaxation responses correlated with adsorbate acidity. This approach offers a molecular-level perspective on interactions within optically opaque porous media.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Ramaraj Ayyappan, Yannick Coppel, Laure Vendier, Sundargopal Ghosh, Sylviane Sabo-Etienne, Sebastien Bontemps
Summary: Four lithium phosphine borohydride compounds with phenyl and naphthyl linkers were synthesized. NMR analysis revealed non-bonded through space P-B coupling. Reactivity towards CO2 resulted in LiH transfer and quantitative formation of ambiphilic phosphine-borane products.
CHEMICAL COMMUNICATIONS
(2021)
Article
Nanoscience & Nanotechnology
Liliana N. Trevani, Cristian M. O. Lepori, Yamila Garro Linck, Gustavo A. Monti, Graciela C. Abuin, Fabian Vaca Chavez, Horacio R. Corti
Summary: The coordination of Si and P in mesoporous silica is affected by temperature and pore size, with high pore size leading to higher electrical conductivity and release rate of PA when exposed to water.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Huan Yan, Selim Alayoglu, Weiqiang Wu, Yongbo Zhang, Eric Weitz, Peter C. Stair, Justin M. Notestein
Summary: The study discovered that depositing differently sized boronic acids into the micropores of silica supports results in different distributions of surface borate species after calcination. These materials exhibit a wide range of rates in ODHP but similar selectivity, indicating they differ only in the numbers of active sites. The correlation between identified features and catalyst activity confirms hydroxylated nonring boron as the likely active site, providing a target for future catalyst syntheses.
Article
Chemistry, Multidisciplinary
Margarita Escudero-Casao, Giulia Licini, Manuel Orlandi
Summary: A novel catalytic system based on copper(I) and chiral bis(phosphine) dioxides has been developed for the arylation of silyl enol ethers, yielding enolizable alpha-arylated ketones with high yields and enantiomeric excess up to 95%. This method is applicable to noncyclic ketones and complements other palladium-catalyzed approaches. Optimization of ligand structure was achieved through rational design driven by correlation analysis, and preliminary mechanistic hypotheses were evaluated to understand the role of chiral bis(phosphine) dioxides.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Applied
Jing Hu, Ruoyi Xu, Jing Hu, Weijun Deng
Summary: In this paper, a dual stabilization method for Pickering emulsions, which can stabilize both the oil phase and the antioxidant, is introduced. The use of mesoporous silica nanospheres (MSN) loaded with an antioxidant called epigallocatechin gallate (EGCG) improves the physical and chemical stabilization of the emulsion. Olfactory evaluation and chemical analysis demonstrate that the Pickering emulsion effectively preserves the odor and chemical compounds of the essential oil.
Article
Chemistry, Multidisciplinary
Giulia Quaglia, Valeria Ambrogi, Donatella Pietrella, Morena Nocchetti, Loredana Latterini
Summary: A solid-state ultraviolet photoreduction process was used to produce Ag-0 nanostructures on mesoporous silica for environmental anti-fouling purposes. The detailed characterization of the materials revealed silica-assisted photo-reduction, leading to the formation of Ag-0 through surface plasmon resonance and morphology changes. The activated silver-silica nanocomposites showed enhanced antimicrobial properties when dispersed in silicon, improving anti-fouling capacity.
Article
Chemistry, Inorganic & Nuclear
Simon G. Rachor, Robert Mueller, Philipp Wittwer, Martin Kaupp, Thomas Braun
Summary: Gold(I) fluoride complexes with phosphine ligands were synthesized from their iodide precursors. Quantum-chemical comparisons between phosphine and N-heterocyclic carbene complexes yielded similar bonding situations. Experimental and calculated F-19 NMR chemical shifts showed good agreement, with phosphine complexes displaying approximately 40 ppm low-field shifts compared to NHC complexes. Reactivity studies of water-sensitive gold(I) fluoride complexes demonstrated metal substitution using trimethylsilyl reagents. The compounds were characterized using NMR and X-ray diffraction methods.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Gao-Liang Zheng, Chenxi Lu, Jin-Pei Cheng, Xin Li
Summary: Efficient kinetic resolution of sulfinamides was achieved via an asymmetric N-allylic alkylation using hydroquinine as a catalyst under mild conditions. The method showed high effectiveness in resolving a range of Morita-Baylis-Hillman adducts and N-aryl tert-butylsulfinamides, with the synthetic utility of the protocol demonstrated through scaled-up reactions. Density functional theory calculations provided convincing evidence for the interpretation of stereoselection.
Article
Biochemical Research Methods
Dan Wang, Xueguo Chen, Juanjuan Feng, Min Sun
Summary: This review focuses on the recent development and application of ordered mesoporous silica materials for solid-phase extraction. Various types of mesoporous silica, including functionalized ones, are discussed in terms of their applications in different solid-phase extraction techniques. The effectiveness of these materials in extracting and determining various target analytes using different detection methods is highlighted, and their successful application in different matrix samples is demonstrated.
JOURNAL OF CHROMATOGRAPHY A
(2022)
