Article
Chemistry, Multidisciplinary
Maria L. G. Sansores-Paredes, Storm van der Voort, Martin Lutz, Marc-Etienne Moret
Summary: Nickelacyclobutanes are reactive intermediates in the reaction of nickel carbenes and olefins, which can selectively decompose into cyclopropanes, metathesis, or beta-hydride elimination pathways depending on the coordination of different coligands. DFT calculations provide insight into the mechanisms of these pathways.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Jakob Lebon, Damir Barisic, Caecilia Maichle-Moessmer, Reiner Anwander
Summary: This article reports the synthesis of a novel yttrium gallabenzene complex from Y(GaMe4)(3) and K(2,4-dtbp) through a tandem salt metathesis/methane elimination reaction, as well as the reactivity of this complex with various Lewis bases.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Tobias Biberger, Nils Noethling, Markus Leutzsch, Christopher P. Gordon, Christophe Coperet, Alois Fuerstner
Summary: In the investigation of ruthenium precatalysts used for light-driven alkyne gem-hydrogenation reactions, a thermally robust anionic dinuclear sigma-dihydrogen complex was found. This complex, formed by the reaction of [(IPr)(eta(6)-cymene)RuCl2] with H-2 under UV-irradiation, is a rare example of anionic sigma-complexes lacking any structural attributes to counterbalance the negative charge and prevent metal center insertion into ligated H-2.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Maria Kourgiantaki, Vera P. Demertzidou, Alexandros L. Zografos
Summary: In this study, the oxy-Cope/ene reaction cascade was used to form a locked elemane conformer, enabling the short and scalable synthesis of versatile Apiaceae scaffolds. The divergent fate of the obtained macrocyclic germacrane was explored under different reaction conditions, leading to the diastereoselective synthesis of oxidized Apiaceae guaiane congeners and the total synthesis of 4-epi-epiguaidiol A. Additionally, the reduction of a hydrogen-bond-biased guaiane substrate allowed for the chemoselective synthesis of desoxo-jungiaguaiane.
Article
Chemistry, Multidisciplinary
Iran Rojas-Leon, Gelen Gomez-Jaimes, Pedro Montes-Tolentino, Wolf Hiller, Hazem Alnasr, Braulio Rodriguez-Molina, Iran F. Hernandez-Ahuactzi, Hiram Beltran, Klaus Jurkschat, Herbert Hopfl
Summary: Hydrolysis reactions of di- and trinuclear organotin halides resulted in large novel cage compounds containing Sn-O-Sn bridges, with octanuclear tetraorganodistannoxanes showing double-ladder motifs. Among them, the co-crystal 2.0.48 I-2 exhibited the largest spacing reported to date for distannoxane-based double ladders. DFT calculations were conducted for both hexanuclear cage compound and a related octanuclear congener alongside experimental work.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Lukas Englert, Uwe Schmidt, Michael Domling, Max Passargus, Tom E. Stennett, Alexander Hermann, Merle Arrowsmith, Marcel Harterich, Jonas Mussig, Alexandra Phillipps, Dominic Prieschl, Anna Rempel, Felix Rohm, Krzysztof Radacki, Fabian Schorr, Torsten Thiess, J. Oscar C. Jimenez-Halla, Holger Braunschweig
Summary: Reactions of terminal acetylenes with doubly Lewis base-stabilised diborenes exhibit distinct outcomes based on temperature and ligand properties, involving either cycloaddition or hydroalkynylation. Phosphine-stabilised diborenes undergo exclusively cycloaddition, leading to significant molecular rearrangement.
Article
Multidisciplinary Sciences
Yunzhou Wen, Cheng Liu, Rui Huang, Hui Zhang, Xiaobao Li, F. Pelayo Garcia de Arquer, Zhi Liu, Youyong Li, Bo Zhang
Summary: In this study, the authors enhance acidic oxygen evolution by introducing strong Bronsted acid sites into RuO2, improving the stability and activity of the catalyst. This strategy could serve as an important reference for the development of stable catalysts.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Sen Yang, Hao Hu, Ming Chen
Summary: A highly efficient visible-light-induced elimination method for alkyl halides is presented, which selectively yields unactivated terminal olefins vital in organic synthesis.
Article
Chemistry, Organic
Sen Yang, Hao Hu, Ming Chen
Summary: A highly efficient method for visible-light-induced regio- and chemoselective elimination of alkyl halides yielding unactivated terminal olefins vital in organic synthesis is presented. The reaction, achieved through ligand control, exhibits remarkable regioselectivity and suppresses undesired side reactions, particularly 1,5-hydrogen atom transfer (HAT). This method favors primary alkyl halides while preserving secondary and tertiary alkyl bromides, thereby enabling the incorporation of terminal olefins in complex molecules for late-stage functionalization.
Article
Chemistry, Multidisciplinary
Mathis J. Benedikter, Janis V. Musso, Wolfgang Frey, Roman Schowner, Michael R. Buchmeiser
Summary: Despite their excellent selectivities and activities, Mo- and W-based catalysts for olefin metathesis have not been widely used due to their air sensitivity. The synthesized cationic-at-metal molybdenum and tungsten imido alkylidene NHC nitrile complexes are stable in air and can catalyze olefin metathesis reactions without prior activation. The presence of a nitrile ligand is crucial for their stability, while variations in imido and anionic ligands affect reactivities and stability.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Tao-Yuan Yu, Qian Niu, Yifa Chen, Meng Lu, Mi Zhang, Jing-Wen Shi, Jiang Liu, Yong Yan, Shun-Li Li, Ya-Qian Lan
Summary: A sevenfold interpenetrating 3D covalent organic framework (TPDT-COF) was synthesized and applied for selective photoisomerization and photocyclization of stilbene under mild conditions. By changing the gas atmosphere, cis-stilbene or phenanthrene can be formed with >99% selectivity. The study provides insights into the application of porous crystalline materials in selective photoisomerization and photocyclization.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Somsuvra Banerjee, Takafumi Kobayashi, Kazuhiko Takai, Sobi Asako, Laurean Ilies
Summary: In the presence of triphenylphosphine as a mild reductant, the use of catalytic amounts of Mo(CO)6 and an ortho-quinone ligand enables the intermolecular reductive coupling of aromatic aldehydes and the intramolecular coupling of aromatic ketones to produce functionalized alkenes. Diaryl-and diheteroaryl alkenes are synthesized with high (E)-selectivity and a tolerance toward bromide, iodide, and steric hindrance. Intramolecular coupling of dicarbonyl compounds under similar conditions affords mono-and disubstituted phenanthrenes.
Review
Chemistry, Multidisciplinary
Dmitry S. Belov, Gabriela Tejeda, Konstantin V. Bukhryakov
Summary: Catalytic olefin metathesis using first-row transition metals, such as scandium to nickel, offers the potential for producing fine and commodity chemicals in a cost-effective and environmentally friendly manner. The unique electronic structure of these base metals allows for unusual reactivity, although the active species involved in olefin metathesis are still not fully understood.
Article
Chemistry, Multidisciplinary
Jessica Rodriguez, Maxime Boudjelel, Leonard J. Mueller, Richard R. Schrock, Matthew P. Conley
Summary: This passage describes the reaction of W(NAr) ((C4H8)-C-13) (OSiPh3)(2) (1) with partially dehydroxylated silica at 700 degrees C. The results show that the reaction outcome is highly influenced by the reaction conditions. Different compounds are formed as products, and their formation is affected by light and heating treatment.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Yang Wang, Biao Ma, Yingning Mao, Zhihui Wang, Jinsong Peng, Chunxia Chen, Zhanyu Li
Summary: This research reports the anti-Markovnikov hydroalkoxylation reaction for the synthesis of Z-enol ethers and provides a mechanistic explanation for their high Z-selectivity. Z-enol ethers can serve as important intermediates for late-stage transformations and gram-scale synthesis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Maximilian Krodel, Lorenz Abduly, Manouchehr Nadjafi, Agnieszka Kierzkowska, Alexander Yakimov, Alexander H. Bork, Felix Donat, Christophe Coperet, Paula M. Abdala, Christoph R. Mueller
Summary: Understanding the effects of different structural parameters of CaO-based CO2 sorbents on cyclic CO2 uptake is crucial for their advancement. Through mechanochemical activation, CaO-based sorbents with varying ratios of Na2CO3:CaCO3 were synthesized to investigate the impact of sodium species on the sorbents' structure, morphology, carbonation rate, and cyclic CO2 uptake. The addition of Na2CO3 in the range of 0.1-0.2 mol% significantly improved CO2 uptake by up to 80% after 10 cycles compared to untreated CaCO3, while higher Na2CO3 loadings (>0.3 mol%) led to a decrease of more than 40% in cyclic CO2 uptake due to accelerated deactivation caused by sintering and the presence of crystalline Na2Ca(CO3)(2) species with high mobility of Na.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Editorial Material
Chemistry, Multidisciplinary
Thomas R. Ward, Christophe Coperet
Article
Chemistry, Multidisciplinary
Paco Laveille, Pascal Mieville, Sourav Chatterjee, Elisa Clerc, Jean-Charles Cousty, Florian de Nanteuil, Erwin Lam, Edy Mariano, Adrian Ramirez, Urielle Randrianarisoa, Keyan Villat, Christophe Coperet, Nicolai Cramer
Summary: The Catalysis Hub - Swiss CAT+ is a funded infrastructure project jointly led by EPFL and ETHZ, which provides a unique integrated technology platform for automated and high-throughput experimentation in sustainable catalytic technologies. Divided into two hubs, EPFL focuses on homogeneous catalysis while ETHZ focuses on heterogeneous catalysis, the platform is open to both academic and private research groups. Through significant investment, both hubs have acquired high-end robotic platforms for synthesis, characterization, and testing of a large number of molecular and solid catalysts. The platforms are accompanied by a fully digitalized experimental workflow and a specific data management strategy to support closed-loop experimentation and advanced computational data analysis.
Article
Chemistry, Multidisciplinary
Seraphine B. X. Y. Zhang, Christophe Coperet
Summary: Non-oxidative coupling of methane (NOCM) is a highly researched reaction that is hindered by harsh reaction conditions and limited catalyst stability. Recent studies have highlighted the importance of catalyst nature and reaction conditions, with metal carbides playing a key role in the incorporation of carbidic carbon. This perspective provides an overview of proposed mechanistic pathways and considerations for experiment conditions, aiming to facilitate a rational catalyst design platform for NOCM.
Article
Chemistry, Multidisciplinary
Zachariah J. Berkson, Ran Zhu, Christian Ehinger, Lukas Latsch, Stefan P. Schmid, Darryl Nater, Stephan Pollitt, Olga V. Safonova, Snaedis Bjorgvinsdottir, Alexander B. Barnes, Yuriy Roman-Leshkov, Gregory A. Price, Glenn J. Sunley, Christophe Coperet
Summary: This article investigated the relationship between olefin metathesis activity of silica-supported molybdenum oxides and metal loading and preparation conditions. Results showed that similar catalysts with different compositions exhibit different reaction properties. The catalyst synthesized via surface organometallic chemistry showed better performance than a classical catalyst with similar metal loading. Solid-state Mo-95 NMR analysis revealed four distinct surface Mo dioxo sites with different distributions depending on the catalyst preparation methods. The intensity of a specific deshielded Mo-95 NMR signal was linked to reducibility and catalytic activity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Daniel F. Abbott, Yuan-Zi Xu, Denis A. Kuznetsov, Priyank Kumar, Christoph R. Mueller, Alexey Fedorov, Victor Mougel
Summary: In this study, the catalytic activity of a Fe-substituted two-dimensional molybdenum carbide in nitrate reduction reaction (NO3RR) was investigated. The results showed that the catalyst exhibited high efficiency in both acidic and neutral media. The formation of surface oxygen vacancies promoted by Fe sites was identified as the active sites for NO3RR, similar to the mechanism of natural Mo-based nitrate reductase enzymes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Seraphine B. X. Y. Zhang, Quentin Pessemesse, Zachariah J. Berkson, Alexander P. Van Bavel, Andrew D. Horton, Pierre-Adrien Payard, Christophe Coperet
Summary: Li/MgO is a prototypical material for oxidative coupling of methane (OCM) with high C-2 selectivity. This study demonstrates that Li/MgO is also an effective catalyst for non-oxidative coupling of methane (NOCM). The presence of Li favors the formation of magnesium acetylide (MgC2), which promotes C-C bond formation and enhances C-2 selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Zixuan Chen, Nora K. Zimmerli, Muhammad Zubair, Alexander V. Yakimov, Snaedis Bjorgvinsdottir, Nicholas Alaniva, Elena Willinger, Alexander B. Barnes, Nicholas M. Bedford, Christophe Coperet, Pierre Florian, Paula M. Abdala, Alexey Fedorov, Christoph R. Mueller
Summary: Gallia-based shells with varying thickness were prepared using atomic layer deposition (ALD) and their atomic-scale structure was studied. The abundance and strength of Lewis acid sites and Bronsted acid sites in the shells were found to correlate with the catalytic performance. This provides insights for the rational design of active Ga-based catalysts.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Moritz Bernhardt, Lukas Latsch, Boris Le Guennic, Christophe Coperet
Summary: This work models surface sites with ten neutral complexes and investigates their potential as single-molecule magnets. The results show that the spatial position of the anionic ligands significantly influences the magnetic properties, while the neutral ligands have a minor role.
HELVETICA CHIMICA ACTA
(2023)
Article
Engineering, Chemical
Quirin Grossmann, Valentina Stampi-Bombelli, Alexander Yakimov, Scott Docherty, Christophe Coperet, Marco Mazzotti
Summary: The optimization of the air-solid contactor is crucial for improving the efficiency of the direct air capture (DAC) process. Two forms of contactors, pellets and wash-coated honeycomb monoliths, are prepared for comparison and potential optimization. The results show that the wash-coated monoliths have similar CO2 uptake compared to the pellets, but exhibit better adsorption kinetics due to their hierarchical pore structure, making them promising candidates for enhancing the efficiency of DAC processes.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Lukas Rochlitz, Jorg W. A. Fischer, Quentin Pessemesse, Adam H. Clark, Anton Ashuiev, Daniel Klose, Pierre-Adrien Payard, Gunnar Jeschke, Christophe Coperet
Summary: This study investigates the effect of Ti doping on the catalytic performance of Pt and PtZn materials in propane dehydrogenation. The results show that Ti-doping significantly changes the electronic structure of nanoparticles and improves the stability of the materials.
Article
Chemistry, Multidisciplinary
Christian Ehinger, Xiaoyu Zhou, Max Candrian, Scott R. Docherty, Stephan Pollitt, Christophe Coperet
Summary: The synthesis of well-defined materials as model systems for catalysis and related fields plays a crucial role in understanding catalytic processes at a molecular level. Organometallic precursors have been developed to produce monodispersed supported nanoparticles, nanocrystals, and films. A new family of precursors based on group 10 metals has been discovered, which can generate small and monodispersed nanoparticles on metal oxides. These precursors show potential for synthesizing bimetallic catalyst materials and have been demonstrated for hydrogenation of CO2 to methanol.
Article
Chemistry, Multidisciplinary
Seraphine B. X. Y. Zhang, Quentin Pessemesse, Lukas Latsch, Konstantin M. Engel, Wendelin J. Stark, Alexander P. van Bavel, Andrew D. Horton, Pierre-Adrien Payard, Christophe Coperet
Summary: Transition metal carbides, such as Mo and W carbides, exhibit excellent properties in terms of hardness, thermal stability, and conductivity, making them popular in catalytic applications. This study reveals the active involvement of carbidic carbon in the formation of C-2 products during methane coupling at high temperature, highlighting the importance of carbon diffusivity and exchange capability on catalyst performance. Mo carbide (Mo2C) shows stable C-2 selectivity over time due to fast carbon diffusion dynamics, while W carbide (WC) exhibits loss of selectivity due to slow diffusion. Overall, this study provides evidence for a Mars-Van Krevelen type mechanism in the non-oxidative coupling of methane.
Article
Chemistry, Multidisciplinary
Wei Zhou, Scott R. Docherty, Christian Ehinger, Xiaoyu Zhou, Christophe Coperet
Summary: Rh-based catalysts modified by Mn were studied for CO2 hydrogenation. The addition of Mn shifts the products from pure CH4 to a mixture of methane and oxygenates. In situ XAS confirms the presence of atomically dispersed Mn-II in the vicinity of metallic Rh nanoparticles, which induces the oxidation of Rh to form the Mn-O-Rh interface under reaction conditions. The formed interface is proposed to be key to maintaining Rh+ sites and promoting the formation of CO and alcohols.
Article
Chemistry, Physical
Zixuan Chen, Alexander I. Serykh, Agnieszka Kierzkowska, David Gajan, Scott R. Docherty, Alexander V. Yakimov, Paula M. Abdala, Christophe Coperet, Pierre Florian, Alexey Fedorov, Christoph R. Mueller
Summary: In this study, we utilized atomic layer deposition to engineer a model PDH catalyst and found that the structural dynamics of surface sites vary with the degree of hydroxylation. The high-performance PDH catalyst possesses isolated tetracoordinate Ga-[4]((4Si)) sites.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
