Article
Chemistry, Multidisciplinary
Iris Berg, Einav Amit, Lillian Hale, F. Dean Toste, Elad Gross
Summary: In this study, a N-heterocyclic carbene (NHC) nanolayer was successfully anchored on the surface of a copper electrode using an electrochemical method, resulting in improved oxidation resistance of copper.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Eloise Angove, Federico Grillo, Herbert A. Fruchtl, Alex J. Veinot, Ishwar Singh, J. Hugh Horton, Cathleen M. Crudden, Christopher J. Baddeley
Summary: The benzannulated N-heterocyclic carbene forms a highly ordered structure on the Cu(111) surface, with vertical benzannulated NHC moieties coordinating to Cu adatoms and three surface-bound benzyl substituents controlling the formation of a highly ordered lattice.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Einav Amit, Iris Berg, Wenhao Zhang, Rajarshi Mondal, Hadar Shema, Vitaly Gutkin, Tatyana Kravchuk, F. Dean Toste, Zackaria Nairoukh, Elad Gross
Summary: In this study, precise spatial control over the self-assembly process of organic self-assembled monolayers (SAMs) in microelectronic devices is achieved by selectively depositing N-heterocyclic carbenes (NHCs) on specific electrodes within a two-microelectrode array using pulsed electrodeposition. Spectroscopic analysis confirms the selective coating of each electrode with a designated NHC. Kelvin probe force microscopy measurements quantitatively demonstrate the impact of NHC monolayers on the electrodes' work function, showing that the work function values of each electrode can be independently tuned by the adsorption of a specific NHC. The presented deposition method allows for the selective coating of designated microelectrodes in an electrode array with chosen NHC monolayers for tuning their chemical and electronic functionality.
Article
Chemistry, Multidisciplinary
Mowpriya Das, Conor Hogan, Robert Zielinski, Milan Kubicki, Maximilian Koy, Canan Kosbab, Simone Brozzesi, Ankita Das, Mike Thomas Nehring, Viktoria Balfanz, Juls Bruehne, Mario Daehne, Martin Franz, Norbert Esser, Frank Glorius
Summary: In this study, we investigated the adsorption properties of N-heterocyclic olefins (NHOs) on silicon and found that the adsorption geometry strongly depends on the N-substituents. Different N-substituents result in different adsorption geometries, with larger N-substituents favoring upright adsorption and smaller N-substituents favoring flat-lying geometry. These different geometries have a significant impact on the properties of the obtained monolayers, such as their work function.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Arne Merschel, Dennis Rottschaefer, Beate Neumann, Hans-Georg Stammler, Mark Ringenberg, Maurice Van Gastel, T. Ilgin Demirer, Diego M. M. Andrada, Rajendra S. S. Ghadwal
Summary: In this study, we have successfully synthesized and isolated two stable anions K[SIPrBp] (4 a-K) and K[IPrBp] (4 b-K). These anions, derived from classical N-heterocyclic carbenes (NHCs), exist as violet crystalline solids.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Nanoscience & Nanotechnology
Yunsoo Choi, Chul Soon Park, Hung-Vu Tran, Chien-Hung Li, Cathleen M. Crudden, Randall Lee
Summary: This study reports the development and use of bench-stable NHC adsorbates for the direct formation of NHC films on gold surfaces under ambient conditions. The generated NHC SAMs were fully characterized and compared to analogous SAMs generated from a different adsorbate. Furthermore, the potential utility of these NHC films as surface-initiated polymerization platforms was demonstrated.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Multidisciplinary Sciences
Alex Inayeh, Ryan R. K. Groome, Ishwar Singh, Alex J. Veinot, Felipe Crasto de Lima, Roberto H. Miwa, Cathleen M. Crudden, Alastair B. McLean
Summary: N-heterocyclic carbenes (NHCs) have emerged as a promising alternative to sulfur-based ligands for self-assembly on gold surfaces, but there are still many unanswered questions about their behavior on surfaces. This study examines fundamental questions such as NHC orientation, mobility, and self-assembly by analyzing NHC overlayers on Au(111).
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Jindong Ren, Maximilian Koy, Helena Osthues, Bertram Schulze Lammers, Christian Gutheil, Marvin Nyenhuis, Qi Zheng, Yao Xiao, Li Huang, Arne Nalop, Qing Dai, Hong-Jun Gao, Harry Moenig, Nikos L. Doltsinis, Harald Fuchs, Frank Glorius
Summary: In this study, NHC polymers consisting of ballbot-type repeating units bound to single Au adatoms were synthesized on gold surfaces. The conformational, electronic, and charge transport properties of these polymers were assessed, and their high surface mobility and potential applications in nanoelectronics, surface functionalization, and catalysis were demonstrated.
Article
Chemistry, Multidisciplinary
Zi-Jing Zhang, Yu-Hua Wen, Jin Song, Liu-Zhu Gong
Summary: The study developed an efficient KR and DyKAT method using N-heterocyclic carbene (NHC)/copper cooperative catalysis, resulting in highly enantioenriched derivatives and products with high structural diversity. Mechanistic studies indicated that NHC can regulate the catalytic activity of the copper catalyst, enabling the switch of chemical selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Zhonggao Zhou, Jing Li, Yangyang Yuan, Liangliang Gao, Peng He, Guotian Luo, Yongrong Xie, Jun Zhang, Guohai Xu, Xiaofei Liao, Shiyong Zhang
Summary: A series of glucopyranoside-based benzimidazolium bromide salts were successfully synthesized and used to stabilize ultra-small and stable gold nanoparticles through one-pot reduction methods. These nanoparticles exhibited excellent stability, strong antibacterial activity, and catalytic activity towards the reduction of nitroarenes.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Multidisciplinary
Bastiaan Kooij, Zhaowen Dong, Paul Varava, Farzaneh Fadaei-Tirani, Rosario Scopelliti, Laura Piveteau, Kay Severin
Summary: This study reports the preparation and structural characterization of vanadium complexes with N-heterocyclic vinylidene ligands, enabled by utilizing diazoolefins as ligand precursors. Structural and theoretical analysis show that N-heterocyclic vinylidenes can act as strong 6e(-) donor ligands, forming strong metal-carbon interactions.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Leonard Karl, Jan Meisner, Christian Ganter
Summary: Attempts were made to synthesize two novel four-membered 1,3-diazetidine based N-heterocyclic carbenes (NHCs) with an organic backbone and a carbonyl functionality. Although the isolated carbenes were not achieved, their respective carbene dimers were obtained in quantitative yield and underwent degradation and rearrangement upon thermal exposure. Some of the thermal reaction species were isolated and characterized, while others were observed using mass spectrometry. Ab initio and density functional theory (DFT) calculations provided a mechanistic explanation for the experimental observations. Classic carbene trapping reactions are still a goal to be achieved due to the strong preference for dimerization.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Runxia Nan, Yiwen Li, Zhouli Zhu, Fan Qi, Xu-Qiong Xiao
Summary: This study focused on the synthesis and transformation of functional groups in metallacarboranes, and investigated their impact on the structure and properties of the metallacarborane framework.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Carmela De Risi, Arianna Brandolese, Graziano Di Carmine, Daniele Ragno, Alessandro Massi, Olga Bortolini
Summary: Oxidative N-heterocyclic carbene (NHC) catalysis has the potential to achieve oxidative and oxygenative transformations, generating various NHC-bound intermediates and enabling non-umpolung processes through the activation of carbon atoms and heteroatoms. This review aims to discuss the recent developments in the field of oxidative NHC catalysis since 2014, with a focus on pivotal intermediates and their mechanistic involvement. More details can be found in the review article by C. De Risi and co-workers.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Review
Chemistry, Multidisciplinary
Carmela De Risi, Arianna Brandolese, Graziano Di Carmine, Daniele Ragno, Alessandro Massi, Olga Bortolini
Summary: Oxidative N-heterocyclic carbene (NHC) catalysis enables oxidative and oxygenative transformations, producing various NHC-bound intermediates and facilitating non-umpolung processes by activating carbon atoms and heteroatoms. This review discusses the developments in the literature on oxidative NHC catalysis since 2014, with a specific focus on pivotal intermediates and their mechanistic involvement.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Editorial Material
Chemistry, Multidisciplinary
Guangying Tan, Frank Glorius
Summary: Stereochemical editing, a recently prominent method, enables direct manipulation of organic molecules with stereocenters to adjust their relative stereochemistry. Various light-driven reactions, such as deracemization and epimerization, have been successfully developed. Wendlandt and colleagues have recently reported a versatile photochemical epimerization of unactivated tertiary stereogenic centers, providing rapid access to challenging stereoisomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Armin Meier, Sabuhi V. Badalov, Timur Biktagirov, Wolf Gero Schmidt, Rene Wilhelm
Summary: A series of new organic dyes incorporating diquat as an electron acceptor unit were synthesized and characterized. DFT calculations supported the analytical data. These dyes exhibited high photocatalytic activity under visible light, achieving isolated yields of up to 97% in the aerobic thiocyanation of indoles and pyrroles. Additionally, the photocatalytic activity of diquat and methyl viologen through formation of an electron donor acceptor complex was demonstrated.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Lukas Meier, Wolf Gero Schmidt
Summary: The adsorption of cyclic (alkyl) (amino) carbenes on the Si(001) surface was studied using density-functional theory. Two adsorption mechanisms, carbene insertion in Si-H bonds and binding to a surface defect, were investigated. The stability of these configurations depended on the hydrogen chemical potential and the molecular side groups. Molecular diffusion was also influenced by the side groups. Adsorption configurations resulted in electronic states within the silicon band gap and a reduction in the work function.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Physics, Condensed Matter
Agnieszka L. Kozub, Uwe Gerstmann, Wolf Gero Schmidt
Summary: The third-order susceptibility Chi(3) of lithium niobate (LiNbO3) is calculated using a Berry-phase formulation of the dynamical polarization based on the electronic structure obtained within density-functional theory (DFT). Maximum |Chi zzzz(3)| values of the order of 10-19 m2 V-2 are calculated for photon energies between 1.2 and 2 eV, which are in the lower half of the optical bandgap of lithium niobate. Both free and bound electron (bi)polarons are found to significantly enhance the third-order susceptibility for photon energies below 1 eV.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Akash Kaithal, Himadri Sekhar Sasmal, Subhabrata Dutta, Felix Schafer, Lisa Schlichter, Frank Glorius
Summary: This study reports a catalytic approach to synthesizing cis-selective saturated carbo-and heterocyclic germanium compounds with a 3D framework through the hydrogenation of readily accessible aromatic germanes with a 2D framework. Nishimura's catalyst exhibited the best hydrogenation reactivity, achieving an isolated yield of up to 96%. The synthesized products showed versatile applications in coupling reactions and demonstrated orthogonal reactivity with boranes or silanes, acquiring a three-dimensional structure with high stability.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Roman Kleinmans, Subhabrata Dutta, Kristers Ozols, Huiling Shao, Felix Schafer, Rebecca E. Thielemann, Hok Tsun Chan, Constantin G. Daniliuc, Kendall N. Houk, Frank Glorius
Summary: The ortho-selective intermolecular photocycloaddition of bicyclic aza-arenes is reported, utilizing a strain-release approach. This reaction enables the construction of C-(sp(3))-rich bicyclo-[2.1.1]-hexanes directly connected to N-heteroarenes. Photophysical experiments and DFT calculations reveal the mechanism of this selective intermolecular photocycloaddition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Yuquan Tong, Yeongju Lee, Xiaohui Liu, Jessica L. Childs-Disney, Blessy M. Suresh, Raphael I. Benhamou, Chunying Yang, Weimin Li, Matthew G. Costales, Hafeez S. Haniff, Sonja Sievers, Daniel Abegg, Tristan Wegner, Tiffany O. Paulisch, Elizabeth Lekah, Maison Grefe, Gogce Crynen, Montina Van Meter, Tenghui Wang, Quentin M. R. Gibaut, John L. Cleveland, Alexander Adibekian, Frank Glorius, Herbert Waldmann, Matthew D. Disney
Summary: Insufficient occupancy of the target, especially for RNA, leads to a lack of biological activity and the difficulty in recognizing RNA structures with small molecules adds to this challenge. By studying the molecular recognition patterns between a small-molecule collection and folded RNA structures, we can map the interaction landscapes across the human transcriptome and define structure-activity relationships. In cases where RNA-binding compounds bind elsewhere and are predicted to be biologically inert, an alternative strategy is to cleave the target through a ribonuclease-targeting chimera, using an RNA-binding molecule appended to a heterocycle that locally activates RNase L-1. Overlaying the substrate specificity of RNase L with the binding landscape of small molecules identifies potential bioactive binders that can be converted into degraders. Proof of concept is provided through the design of selective degraders for pre-miR-155, JUN mRNA, and MYC mRNA, demonstrating the potential of small-molecule RNA-targeted degradation as potent and specific modulators of RNA function.
Article
Materials Science, Multidisciplinary
S. Badalov, A. Bocchini, R. Wilhelm, A. L. Kozub, U. Gerstmann, W. G. Schmidt
Summary: In this study, the structural, electronic, and optical properties of TiO2 crystals were calculated using Hubbard U correction and hybrid functional methods in density-functional theory. The results were compared with experimental observations, and it was found that the modified hybrid functionals and DFT + U method can provide accurate atomic structures and electronic structure data. The methods were also applied to study TiO2 amorphous ultra-thin films, and the agreement between the two methods was confirmed even for small details of the optical spectra.
MATERIALS RESEARCH EXPRESS
(2023)
Article
Chemistry, Multidisciplinary
Mowpriya Das, Conor Hogan, Robert Zielinski, Milan Kubicki, Maximilian Koy, Canan Kosbab, Simone Brozzesi, Ankita Das, Mike Thomas Nehring, Viktoria Balfanz, Juls Bruehne, Mario Daehne, Martin Franz, Norbert Esser, Frank Glorius
Summary: In this study, we investigated the adsorption properties of N-heterocyclic olefins (NHOs) on silicon and found that the adsorption geometry strongly depends on the N-substituents. Different N-substituents result in different adsorption geometries, with larger N-substituents favoring upright adsorption and smaller N-substituents favoring flat-lying geometry. These different geometries have a significant impact on the properties of the obtained monolayers, such as their work function.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Physics, Applied
F. F. Murzakhanov, M. A. Sadovnikova, G. V. Mamin, S. S. Nagalyuk, H. J. von Bardeleben, W. G. Schmidt, T. Biktagirov, U. Gerstmann, V. A. Soltamov
Summary: In this study, the interaction parameters of nitrogen-vacancy (NV) centers in 4H silicon carbide were investigated using high-frequency electron-nuclear double resonance spectroscopy and first-principles density functional theory. It was found that different NV configurations have different electron-nuclear interaction parameters, suggesting that each NV center can act as a separate optically addressable qubit.
JOURNAL OF APPLIED PHYSICS
(2023)
Review
Chemistry, Multidisciplinary
Peter Bellotti, Frank Glorius
Summary: The concept of strain in organic compounds is essential for understanding the synthesis and properties of organic compounds. Recent advancements in strain-release reactions and photocatalysis have opened up new possibilities for creating unique chemical architectures and expanding the field of strain research.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Huamin Wang, Johannes E. Erchinger, Madina Lenz, Subhabrata Dutta, Constantin G. Daniliuc, Frank Glorius
Summary: This study presents a photoredox strategy that enables the high regio- and syn-selective difunctionalization of bicyclo[1.1.0]-butanes (BCBs). By cleaving C-S sigma bonds, sulfur-alkynylation, -alkenylation, and -allylation of BCBs can be achieved under mild conditions, demonstrating the generality of this approach.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Crystallography
Sergej Neufeld, Uwe Gerstmann, Laura Padberg, Christof Eigner, Gerhard Berth, Christine Silberhorn, Lukas M. Eng, Wolf Gero Schmidt, Michael Ruesing
Summary: This study calculated the phonon spectra of potassium titanyl phosphate and related compounds using density functional theory and compared them with experimental data, providing a more detailed assignment of spectral features. The findings improve the foundation for understanding the vibrational properties of the KTiOPO4 material family.
Review
Chemistry, Multidisciplinary
Lukas Lueckemeier, Marco Pierau, Frank Glorius
Summary: This review aims to present the state-of-the-art in transition-metal catalysed asymmetric hydrogenation of (hetero)arenes, highlighting recent advances and important trends, and providing a broad overview for the reader.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Organic
Tristan Wegner, Anna L. L. Matos, Karine Porte, Kira Mehring, Marco Pierau, Hendrik Horstmeier, Volker Gerke, Frank Glorius
Summary: Cholesterol is a vital lipid in cellular membranes and plays a role in various cellular processes. Diseases like immunological disorders and cancer have been associated with abnormalities in cholesterol homeostasis. Thus, there is a need for molecular tools to study cholesterol distribution and interactions. In this study, a novel bifunctional imidazolium-based cholesterol analog (X-CHIM) was synthesized, which can serve as a versatile tool for investigating cellular cholesterol distributions and cholesterol-protein interactions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)