Article
Chemistry, Multidisciplinary
Robin Rothfelder, Verena Streitferdt, Ulrich Lennert, Jose Cammarata, Daniel J. Scott, Kirsten Zeitler, Ruth M. Gschwind, Robert Wolf
Summary: Detailed P-31{H-1} NMR spectroscopic investigations provide deeper insight into the mechanisms involved in the photocatalytic arylation of white phosphorus, revealing previously unrecognized side products and the unexpected behavior of the terminal reductant Et3N. The different rate of formation of these products explains the performance discrepancies of two effective catalysts, while the observation of PH3 as a minor intermediate led to the development of a new catalytic procedure for the arylation of white phosphorus. This method yields valuable triarylphosphines or tetraarylphosphonium salts depending on aryl substituents' steric profiles.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Jiaxin Gao, Rick W. Dorn, Guillaume P. Laurent, Frederic A. Perras, Aaron J. Rossini, Matthew P. Conley
Summary: The silylium-like surface species [(Pr3Si)-Pr-i]-[(O-F)(3)Al-OSi )] activates (N boolean AND N)Pd(CH3)Cl by chloride ion abstraction to form [(N boolean AND N)Pd-CH3][((RO)-O-F)(3)Al-OSi )]. This activation shows similar reactivity patterns as (N boolean AND N)Pd(CH3)Cl activated with Na[B(Ar-F)(4)]. In addition, this activated species can catalyze the polymerization of ethylene and copolymerize with methyl acrylate.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Physical
Ekaterina V. Pokochueva, Dudari B. Burueva, Oleg G. Salnikov, Igor V. Koptyug
Summary: HET-PHIP has attracted significant research attention in recent years, showing major prospects for applications in biomedical MRI and industrial catalytic studies, despite the current need for further improvement in NMR signal enhancements.
Review
Chemistry, Multidisciplinary
Majid Vafaeezadeh, Werner R. Thiel
Summary: This review systematically covers recent and significant achievements in the application of task-specific Janus nanomaterials as heterogeneous catalysts in various types of chemical reactions, and provides an outlook on possible future applications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Multidisciplinary
Lifei Lian, Huaiying Zhang, Sai An, Wei Chen, Yu-Fei Song
Summary: POMs, as a class of discrete anionic metal-oxygen clusters with tunable structure, exhibit super strong Bransted acidity, high proton mobility, and thermal stability, making them potential green alternatives to conventional homogeneous acid catalysts. Through design strategies such as functionalized cations, covalent interactions, non-precious metal support, and porous polymer framework, POMs-based heterogeneous catalysts have shown excellent catalytic performance in specific acid-catalyzed reactions.
SCIENCE CHINA-CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Tiancheng Pu, Wenhao Zhang, Minghui Zhu
Summary: Strong metal-support interactions (SMSI) is a classic yet fast-growing area in catalysis research. By regulating the interfacial interactions, SMSI phenomenon can encapsulate and stabilize metal nanoparticles, significantly impacting catalytic performance. Engineering SMSI provides a promising approach to steer catalytic performance and tackle energy and environmental challenges effectively.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Engineering, Chemical
Yani Guan, Donovan Chaffart, Guihua Liu, Zhaoyang Tan, Dongsheng Zhang, Yanji Wang, Jingde Li, Luis Ricardez-Sandoval
Summary: The recent application of machine learning in the development of new heterogeneous catalysts has shown significant progress in establishing relationships between material properties and catalytic performance, improving efficiency in design and screening guidelines. However, accurate prediction of high-performance catalysts still presents challenges.
CHEMICAL ENGINEERING SCIENCE
(2022)
Review
Chemistry, Multidisciplinary
Zhaohua Li, Rui Hu, Shuai Ye, Jun Song, Liwei Liu, Junle Qu, Weiguo Song, Changyan Cao
Summary: This article summarizes the recent advancements and classification of wettability-induced high-performance heterogeneous thermocatalysis, including the effects of different wettabilities on catalytic performance. Wettability regulation can enhance molecular diffusion, leading to high activity and high selectivity of reactants and products.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Review
Chemistry, Physical
Mi Xiong, Zhe Gao, Yong Qin
Summary: Spillover, a well-known phenomenon in heterogeneous catalysis, has opened up a new research field for understanding the dynamic behavior of migrated species on catalyst surfaces. Recent advances in characterization techniques and synthesis methodologies have provided valuable information about spillover. The review mainly focuses on recent progress in the characterization and mechanism of hydrogen spillover, as well as utilizing the spillover effect for enhanced catalytic performance, while discussing remaining challenges and possible future research directions.
Review
Materials Science, Paper & Wood
Zhengqiu Yuan, Wei Dai, Shenghong Zhang, Fengxin Wang, Jian Jian, Jianxian Zeng, Hu Zhou
Summary: This review provides an in-depth analysis and evaluation of the research achievements in the field of heterogeneous chemical catalysis technologies for the production of value-added chemicals from lignocellulosic polysaccharides. The possibilities and potential for further industrial implementation are discussed and critically evaluated.
Article
Chemistry, Multidisciplinary
Gang Yang, Jing-He Cen, Jian Lan, Meng-Yuan Li, Xuan Zhan, Gao-Qing Yuan, Hai-Yang Liu
Summary: A new phosphorus(V) complex [(TPFC)P-V(OH)(2)] was reported as an electrocatalyst for the hydrogen evolution reaction (HER), showing excellent activity and stability. It can serve as a sustainable alternative to precious metal catalysts.
Article
Chemistry, Physical
Weiyu Wang, Qiang Wang, Jun Xu, Feng Deng
Summary: Parahydrogen-induced polarization (PHIP) is a technique that can increase the NMR sensitivity by several orders. It is a powerful tool to characterize catalyst properties and elucidate reaction mechanisms. In this Perspective, the heterogeneous PHIP (HET-PHIP) technique and its application in catalytic hydrogenation are comprehensively reviewed. The fundamentals of HET-PHIP are introduced and its ability to provide information about catalyst morphology and electronic properties is discussed. The mechanistic understanding of catalytic hydrogenations using HET-PHIP is also discussed.
Article
Chemistry, Physical
Weiyu Wang, Qiang Wang, Jun Xu, Feng Deng
Summary: Parahydrogen-induced polarization (PHIP) is an NMR hyperpolarization technique that enhances NMR sensitivity. This technique generates hyperpolarization through pairwise addition behavior, making it useful for catalyst characterization and understanding reaction mechanisms. This Perspective provides a comprehensive overview of the heterogeneous PHIP (HET-PHIP) technique and its applications in catalytic hydrogenation. The fundamentals of HET-PHIP are introduced, along with its ability to provide information about catalyst morphology and electronic properties. The paper also discusses advancements in mechanistic understanding achieved using HET-PHIP and the limitations and prospects of this technique.
Article
Chemistry, Multidisciplinary
A. N. Korovin, I. S. Humonen, A. I. Samtsevich, R. A. Eremin, A. I. Vasilev, V. D. Lazarev, S. A. Budennyy
Summary: The discovery of new catalysts is important for computational chemistry and renewable energy. Recent advancements in deep learning approaches, such as graph neural networks, can greatly expand the modeling of high-performance catalysts. However, the graph representation of crystal structures is challenging due to their complex connectivity. In this study, we propose an improved graph neural network using Voronoi tessellation to predict the energy of catalytic systems. The proposed modifications enhance the accuracy of the original model, achieving a mean absolute error of 651 meV on the Open Catalyst Project dataset and 6 meV/atom on the intermetallics dataset. Additionally, considering an additional dataset, the error can be reduced below the physically-based threshold of 20 meV/atom.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Chemistry, Physical
Carlos Lizandara-Pueyo, Xinyuan Fan, Carles Ayats, Miquel A. Pericas
Summary: This study involved the controlled synthesis of calcium carbonate particles surface-functionalized with azido groups, followed by copper-catalyzed alkyne-azide cycloaddition reactions to prepare novel catalytic materials. The immobilized catalyst demonstrated high selectivity and efficiency in catalyzing Michael addition reactions of aldehydes, with the added advantage of being reusable and adaptable to continuous-flow operation for increased productivity.
JOURNAL OF CATALYSIS
(2021)
Editorial Material
Physics, Atomic, Molecular & Chemical
Daniel Abergel, Gerd Buntkowsky, Konstantin L. Ivanov, Perunthiruthy K. Madhu
APPLIED MAGNETIC RESONANCE
(2021)
Article
Biochemistry & Molecular Biology
Tomasz Ratajczyk, Gerd Buntkowsky, Torsten Gutmann, Bartlomiej Fedorczyk, Adam Mames, Mariusz Pietrzak, Zuzanna Puzio, Piotr Grzegorz Szkudlarek
Summary: The biorelevant PyFALGEA oligopeptide ligand has been successfully utilized in SABRE experiments for signal amplification, with its interaction with the iridium catalyst influencing the efficiency of hyperpolarization. Steric hindrance caused by the bulky phenylalanine in the PyFALGEA oligopeptide can hinder hyperpolarization, highlighting the importance of optimizing the molecular structures for efficient hyperpolarization. Additionally, a unique NMR pattern in the hydride region observed during SABRE experiments with PyFALGEA and IMesBn can serve as a fingerprint for this oligopeptide.
Article
Chemistry, Multidisciplinary
J. Eills, E. Cavallari, R. Kircher, G. Di Matteo, C. Carrera, L. Dagys, M. H. Levitt, K. L. Ivanov, S. Aime, F. Reineri, K. Muennemann, D. Budker, G. Buntkowsky, S. Knecht
Summary: This study introduces a novel H-1 imaging method in which hyperpolarized spin order is released for imaging through a specific biochemical reaction, while suppressing background signals from water. It allows for hyperpolarized imaging without the need for low-abundance, low-sensitivity heteronuclei.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Vytautas Klimavicius, Harald Hilbig, Torsten Gutmann, Gerd Buntkowsky
Summary: Solid-state NMR combined with dynamic nuclear polarization (DNP NMR) was used to study hydration processes in tricalcium silicate (C3S) samples. The appearance of Q(3) and Q(4) lines in the spectra indicated the formation of amorphous silica in partly hydrated C3S samples, which was corroborated by FTIR data. Significant DNP signal enhancements allowed for further investigation into the C3S carbonation process and direct observation of carbonate moieties formation in partly hydrated C3S samples using various techniques.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Mohamad Srour, Sara Hadjiali, Kai Brunnengraeber, Heiko Weidler, Yeping Xu, Hergen Breitzke, Torsten Gutmann, Gerd Buntkowsky
Summary: A novel immobilized Wilkinson's catalyst [SiO2 similar to PvPy-Wilk] was synthesized and confirmed through 1D and 2D multinuclear solid-state NMR techniques. The catalyst showed significant structural changes after reaction cycles, leading to activation, and exhibited about 200-fold enhancement in signals of the hydrogenation product ethylbenzene in PHIP experiments.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Laurynas Dagys, Vytautas Klimavicius, Martin Brodrecht, Gerd Buntkowsky, Vytautas Balevicius
Summary: The study investigated cross-polarization with magic-angle spinning (CP MAS) kinetics between remote spins in various selected materials, aiming to understand the thermal equilibration pathways and determine the fractal dimensions. The results suggest that different compounds exhibit distinct fractal dimensions, with thermal equilibration mediated primarily through strong interatomic/intramolecular vibrations and high proton mobility along H-bonds.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2021)
Article
Multidisciplinary Sciences
Stephan Knecht, John W. Blanchard, Danila Barskiy, Eleonora Cavallari, Laurynas Dagys, Erik Van Dyke, Maksim Tsukanov, Bea Bliemel, Kerstin Muennemann, Silvio Aime, Francesca Reineri, Malcolm H. Levitt, Gerd Buntkowsky, Alexander Pines, Peter Bluemler, Dmitry Budker, James Eills
Summary: This study discusses the techniques of hyperpolarizing fumarate using dissolution dynamic nuclear polarization and parahydrogen-induced polarization, as well as the method of purifying pure solid fumarate from impurities through acid precipitation.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Physics, Atomic, Molecular & Chemical
Laura Wienands, Franziska Theiss, James Eills, Lorenz Roesler, Stephan Knecht, Gerd Buntkowsky
Summary: Parahydrogen-induced polarization is a hyperpolarization method that enhances nuclear magnetic resonance signals through chemical reactions involving the para spin isomer of hydrogen gas. This method allows for biomolecules to be hyperpolarized for real-time in vivo metabolic imaging. Current research on the efficient hyperpolarization of fumarate has not been thoroughly investigated, leading to inconsistencies in chosen reaction conditions in previous work seeking higher reaction rates and yields.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Physical
Florian Venel, Hiroki Nagashima, Andrew G. M. Rankin, Christelle Anquetil, Vytautas Klimavicius, Torsten Gutmann, Gerd Buntkowsky, Sylvie Derenne, Olivier Lafon, Arnaud Huguet, Frederique Pourpoint
Summary: Estuaries are important ecosystems with unique biodiversity and economic importance. Variations in environmental parameters along estuaries can modify the characteristics of dissolved organic matter (DOM). Solid-state NMR spectroscopy, particularly with dynamic nuclear polarization, allows for enhanced sensitivity and faster acquisition of NMR spectra for studying the functional groups in DOM. This technology reveals insights into the nitrogen and carbon environments in DOM samples from the Seine estuary.
Article
Thermodynamics
Markus M. Hoffmann, Joseph D. Kealy, Torsten Gutmann, Gerd Buntkowsky
Summary: The study investigated the physical properties of polyethylene glycol (PEG) and its binary mixtures, finding a linear relationship between temperature and density, while viscosity and self-diffusion coefficients followed the Arrhenius law. Calculated molar volumes largely agreed with measured values, viscosities were mostly within a few percent, and self-diffusion coefficients were generally within 20% of measurement uncertainty.
JOURNAL OF CHEMICAL AND ENGINEERING DATA
(2022)
Article
Biochemistry & Molecular Biology
Nargiz B. Asanbaeva, Larisa Yu Gurskaya, Yuliya F. Polienko, Tatyana Rybalova, Maxim S. Kazantsev, Alexey A. Dmitriev, Nina P. Gritsan, Nadia Haro-Mares, Torsten Gutmann, Gerd Buntkowsky, Evgeny Tretyakov, Elena G. Bagryanskaya
Summary: This study investigates the feasibility of using ferrocene-substituted 1,3-diazetidine-2,4-diimine couplers as DNP agents. The results show that the spiro-substituted nitroxyl biradicals have a higher DNP gain compared to the methyl-substituted biradicals. The difference in temperature dependence of the EPR spectra is explained using DFT calculations. The effects of nucleophiles and substituents on the ring-opening reaction and the influence of ring opening on the exchange interaction are also examined.
Article
Chemistry, Physical
Markus M. Hoffmann, Matthew D. Too, Nathaniel A. Paddock, Robin Horstmann, Sebastian Kloth, Michael Vogel, Gerd Buntkowsky
Summary: In this study, molecular dynamics simulations were performed to investigate polyethylene glycol (PEG)200. Force fields for describing ethylene glycol oligomers were tested and adjusted to improve the agreement with experimental properties. The simulations revealed that PEG200 is a random mixture of its ethylene glycol oligomer components.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Physical
Sonja C. Doeller, Torsten Gutmann, Markus Hoffmann, Gerd Buntkowsky
Summary: This study investigates the behavior of four different commercially available polarizing agents using 1-octanol as the analyte. By establishing a relative method to compare the direct and indirect polarization transfer pathways, it is possible to directly compare the polarization efficacy for different radicals and different parts of the 1-octanol molecule. The results highlight the importance of hydrophilicity in the polarization transfer process.
SOLID STATE NUCLEAR MAGNETIC RESONANCE
(2022)
Article
Biochemistry & Molecular Biology
Nargiz B. B. Asanbaeva, Sergey A. A. Dobrynin, Denis A. A. Morozov, Nadia Haro-Mares, Torsten Gutmann, Gerd Buntkowsky, Elena G. G. Bagryanskaya
Summary: This paper reports on the DNP efficiency at a high magnetic field for two water-soluble biradicals resistant to reducing media. The radicals were obtained in the form of quaternary ammonium salts to achieve water solubility. The influence of hyperfine interaction and exchange interaction on the DNP effect was determined through EPR spectroscopy.
Article
Chemistry, Physical
Niels Rothermel, Hans-Heinrich Limbach, Iker del Rosal, Romuald Poteau, Gabriel Mencia, Bruno Chaudret, Gerd Buntkowsky, Torsten Gutmann
Summary: Ruthenium nanoparticles stabilized with dppb and hydrogen were exposed to (NH3)-N-15 gas, leading to the formation of surface-bound urea. The pressure of hydrogen gas affects the chemical shifts of RuNH2 on the surface.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)