Article
Chemistry, Inorganic & Nuclear
Om Prakash, Linnea Lindh, Nidhi Kaul, Nils W. Rosemann, Iria Bolano Losada, Catherine Johnson, Pavel Chabera, Aleksandra Ilic, Jesper Schwarz, Arvind Kumar Gupta, Jens Uhlig, Tore Ericsson, Lennart Haggstrom, Ping Huang, Jesper Bendix, Daniel Strand, Arkady Yartsev, Reiner Lomoth, Petter Persson, Kenneth Warnmark
Summary: Fe(III) complexes with N-heterocyclic carbene (NHC) ligands, which have long-lived luminescent charge-transfer excited states, can be used as photosensitizers for charge separation reactions. Three new hexa-NHC complexes were synthesized and characterized, showing favorable properties in their excited states even with modifications in the ligand framework, demonstrating the robustness of the scorpionate motif.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yu-Yang Zhou, Yang-Ming Ding, Wei Zhao, Jian-Hua Dong, Liang-Zhi Li, Hong-Yuan Chen, Jing-Juan Xu
Summary: Three new ruthenium(ii) complexes with N-heterocyclic carbene ligands have been synthesized and shown to be efficient near-infrared ECL luminophores. These complexes demonstrate higher or comparable ECL efficiency compared to traditional Ru(bpy)(3)(2+), indicating great potential for future applications in NIR ECL imaging.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Weiyang Bi, Yunhui Yang, Song Ye, Congyang Wang
Summary: The umpolung cross-coupling reaction of pyridine-2-carboxaldehydes and propargylic carbonates was successfully achieved for the first time through N-heterocyclic carbene/palladium cooperative catalysis. The judicious selection of the palladium catalyst, ligand, and N-heterocyclic carbene resulted in regioselective formation of propargylic ketones.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Liang Yang, Shiyao Deng, Yong Pei
Summary: The structure and bonding properties of N-heterocyclic carbene (NHC) protected silver nanoclusters were investigated using Density Functional Theory (DFT) calculations. The calculations revealed that NHC-VI exhibited the best substituent effect in these silver clusters. These theoretical results provide new insights into the stabilization mechanism of NHC-stabilized atomically precise silver clusters and could assist in the experimental construction of such clusters.
CHEMICAL PHYSICS LETTERS
(2023)
Review
Chemistry, Inorganic & Nuclear
Moushakhi Ghosh, Shabana Khan
Summary: This article highlights the recent developments in silylene-coinage metal chemistry, focusing on synthetic approaches, unusual properties, and catalytic efficiency of these complexes. Further research is needed to explore the potential of silylene-coinage metal complexes in various chemical reactions.
DALTON TRANSACTIONS
(2021)
Article
Biochemical Research Methods
Fady Nahra, Nikolaos Tzouras, Alba Collado, Steven P. Nolan
Summary: N-heterocyclic carbene gold(I) chloride and hydroxide complexes are commonly used as synthetic reagents and efficient catalysts. This study describes a straightforward and practical method for synthesizing mononuclear gold complexes with high yields, as well as the synthesis of a mononuclear gold(I) hydroxide complex and an improved synthesis method for a dinuclear gold(I) hydroxide complex. This methodology offers advantages such as the use of sustainable reaction solvents and commercially available starting materials.
Article
Biochemistry & Molecular Biology
Oscar A. Lenis-Rojas, Sandra Cordeiro, Marta Horta-Meireles, Jhonathan Angel Araujo Fernandez, Sabela Fernandez Vila, Juan Andres Rubiolo, Pablo Cabezas-Sainz, Laura Sanchez, Alexandra R. Fernandes, Beatriz Royo
Summary: The study evaluated the antiproliferative activity of Fe(II) cyclopentadienyl complexes with n-heterocyclic carbene ligands in tumor cells, showing that Fe1 displayed high cytotoxic activity in both human colorectal carcinoma cells and ovarian carcinoma cells, with lower in vivo toxicity compared to cisplatin. In vivo analyses using colorectal HCT116 zebrafish xenograft showed that both Fe1 and Fe2 compounds reduced the proliferation of human HCT116 colorectal cancer cells.
Review
Chemistry, Inorganic & Nuclear
Pavel Chabera, Linnea Lindh, Nils W. Rosemann, Om Prakash, Jens Uhlig, Arkady Yartsev, Kenneth Warnmark, Villy Sundstrom, Petter Persson
Summary: Recent investigations have shown promising photophysical and photochemical properties of iron(III) NHC complexes, including nanosecond photoluminescence and capabilities to drive both photo-oxidation and photo-reduction reactions. These results are important for understanding the unorthodox photophysical and photochemical properties associated with this open-shell electronic configuration.
COORDINATION CHEMISTRY REVIEWS
(2021)
Article
Chemistry, Inorganic & Nuclear
Amy L. Speelman, Kazimer L. Skubi, Brandon Q. Mercado, Patrick L. Holland
Summary: Recent experimental evidence indicates that during N-2 reduction, the FeMoco of nitrogenase undergoes structural rearrangement, leading to the generation of coordinatively unsaturated iron sites. New designed ligands have shown the potential flexibility in structural arrangement of metal complexes, mimicking the resting state of nitrogenase.
INORGANIC CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Taoufik Rohand, Hicham Ben El Ayouchia, Hafid Achtak, Adib Ghaleb, Yavuz Derin, Ahmet Tutar, Kiyoshi Tanemura
Summary: This study focuses on the synthesis of Schiff base and its coordination with metal ions, investigating their structures, properties, reactivity in organic reactions, and antibacterial activity. The results indicate the potential application of these complexes in medicinal chemistry.
JOURNAL OF BIOMOLECULAR STRUCTURE & DYNAMICS
(2022)
Article
Biochemistry & Molecular Biology
Taoufik Rohand, Hicham Ben EL Ayouchia, Hafid Achtak, Adib Ghaleb, Yavuz Derin, Ahmet Tutar, Kiyoshi Tanemura
Summary: A bidentate Schiff base and its 1,3,4-oxadiazole complexes were synthesized and characterized, showing strong electrophilic or nucleophilic tendencies in polar organic reactions, and enhanced antibacterial activity. The metal ions formed stable complexes with the Schiff base, exhibiting higher affinity towards chromium ions and improved biological activity, suggesting potential applications in antimicrobial therapy.
JOURNAL OF BIOMOLECULAR STRUCTURE & DYNAMICS
(2021)
Review
Chemistry, Inorganic & Nuclear
Qiuming Liang, Datong Song
Summary: This article highlights the recent development of mesoionic N-heterocyclic olefins (mNHOs), which possess unquenched basicity and nucleophilicity, leading to unique reactivity patterns.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Yanhong Dong, Shangqing Xie, Peng Zhang, Qingqing Fan, Xinyu Du, Hongjian Sun, Xiaoyan Li, Olaf Fuhr, Dieter Fenske
Summary: Six silyl cobalt(III) hydrides were synthesized with different substituents at the P and Si atoms, among which complex 3 exhibited excellent anti-Markovnikov regioselectivity as the best catalyst for alkene hydrosilylation. Addition of pyridine N-oxide reversed the selectivity of the reaction from anti-Markovnikov to Markovnikov addition, while maintaining high yield and excellent selectivity at a lower temperature. The proposed reaction mechanisms were based on experimental information, and the molecular structures of the complexes were determined by single crystal X-ray diffraction analysis.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Aya Eizawa, Kazuya Arashiba, Hiromasa Tanaka, Asuka Konomi, Kazunari Yoshizawa, Yoshiaki Nishibayashi
Summary: In this study, dimolybdenum complexes with quaterphenylene-bridged PNP-type pincer ligands were designed and synthesized based on DFT calculations. The results showed that these complexes exhibited excellent catalytic activity for the synthesis of ammonia from dinitrogen under ambient conditions using samarium diiodide as a reductant and water as a proton source.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Aya Eizawa, Kazuya Arashiba, Hiromasa Tanaka, Asuka Konomi, Kazunari Yoshizawa, Yoshiaki Nishibayashi
Summary: Dimolybdenum complexes bearing 3,3'''-(1,1':3',1'':3'',1'''-quaterphenylene)-bridged pyridine-based PNP-type pincer ligand were designed and prepared based on DFT calculations. These complexes serve as effective catalysts for the conversion of dinitrogen to ammonia under ambient reaction conditions, using samarium diiodide as a reductant and water as a proton source.
DALTON TRANSACTIONS
(2023)
Article
Electrochemistry
Natalia Levin, Carla Casadevall, George E. Cutsail, Julio Lloret-Fillol, Serena DeBeer, Olaf Ruediger
Summary: In this study, a molecular Ru-based water oxidation catalyst bearing a polypyridinic backbone was investigated using in situ spectroelectrochemistry coupled with EPR and XAS techniques. The study proposed a water nucleophilic attack mechanism for O-O bond formation, and observed intermediates supporting this mechanism, including a Ru(V) oxo intermediate based on the Py(2)Metacn ligand for the first time.
Article
Chemistry, Multidisciplinary
Charafa Souilah, Sergio A. Jannuzzi, Derya Demirbas, Sergei Ivlev, Marcel Swart, Serena DeBeer, Alicia Casitas
Summary: This study discloses a new reactivity mode for electrophilic cyano lambda(3)-iodanes as group transfer one-electron oxidants, which can be used to synthesize Fe-III and Fe-IV cyanide complexes. The synthesis of these complexes was achieved through consecutive single electron transfer processes or oxidation reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Casey Van Stappen, Bardi Benediktsson, Atanu Rana, Aleksandr Chumakov, Yoshitaka Yoda, Dimitrios Bessas, Laure Decamps, Ragnar Bjornsson, Serena DeBeer
Summary: In this study, the electronic structure and dynamics of the catalytic components of three unique M N(2)ase enzymes (M = Mo, V, Fe) were investigated using synchrotron-based Fe-57 nuclear resonance vibrational spectroscopy and DFT-based QM/MM calculations. The results provide vibrational mode assignments for the FeMco clusters and demonstrate the sensitivity of the calculated partial vibrational density of states to the geometric and electronic structures of these clusters. The study also discusses the challenges faced when using NRVS to investigate large, multi-component metalloenzymatic systems and outlines the scope and limitations of current theory in reproducing complex spectra.
FARADAY DISCUSSIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Sivathmeehan Yogendra, Daniel W. N. Wilson, Anselm W. Hahn, Thomas Weyhermuller, Casey Van Stappen, Patrick Holland, Serena DeBeer
Summary: This article reports a series of di-iron clusters supported by dianionic yldiide ligands, in which the Fe sites are bridged by two mu 2-C atoms and four pendant S donors. The mixed-valence cluster displays two peaks in the Moessbauer spectra, indicating slow electron transfer between the two sites.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Martin Keilwerth, Weiqing Mao, Sergio A. V. Jannuzzi, Liam Grunwald, Frank W. Heinemann, Andreas Scheurer, Joerg Sutter, Serena DeBeer, Dominik Munz, Karsten Meyer
Summary: Terminal imido complexes of iron have been widely studied in metal-catalyzed nitrogen-transfer chemistry. In this study, a new tris-NHC chelating ligand (TIMMNMes) was used to synthesize and compare two series of iron alkyl imido complexes, including a reactive Fe(V) adamantyl imido intermediate. The stability and reactivity of these complexes were investigated using various characterization techniques and quantum chemical calculations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Carli B. Kovel, Jonathan M. Darmon, S. Chantal E. Stieber, Gisselle Pombar, Tyler P. Pabst, Bastian Theis, Zoe R. Turner, Okten Ungor, Michael Shatruk, Serena DeBeer, Paul J. Chirik
Summary: This article describes the application of bimolecular reductive elimination in the activation of iron catalysts for alkene-diene cycloaddition. The synthesis, characterization, electronic structure determination, and solution stability of a family of pyridine(diimine) iron methyl complexes with diverse steric properties and electronic ground states were key to this approach. These complexes exhibited distorted molecular structures and S = 3/2 ground states. The addition of butadiene to these complexes induced ethane formation and activated the iron catalysts for the cycloaddition reaction.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Weiqing Mao, Zihan Zhang, Dominik Fehn, Sergio A. V. Jannuzzi, Frank W. Heinemann, Andreas Scheurer, Maurice van Gastel, Serena DeBeer, Dominik Munz, Karsten Meyer
Summary: This study describes the synthesis, characterization, and reactivity of a series of cobalt terminal imido complexes supported by an N-anchored tripodal tris(carbene) chelate. The complexes were fully characterized using various spectroscopic and crystallographic techniques. Quantum chemical calculations provided insight into the electronic structures of the compounds. The findings highlight the reactivity of these cobalt imido complexes, including their ability to undergo intramolecular C-H bond amination and nucleophilic addition reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yuyan Zhang, Sami El Sayed, Liqun Kang, Matthew Sanger, Thomas Wiegand, Philip G. Jessop, Serena Debeer, Alexis Bordet, Walter Leitner
Summary: Ruthenium nanoparticles immobilized on an amine-functionalized polymer-grafted silica support can selectively catalyze the hydrogenation of bicyclic heteroaromatics. The addition of CO2 to the hydrogen gas phase can effectively shut down the arene hydrogenation reaction while maintaining activity for heteroaromatic hydrogenation. This selectivity switch is achieved through the catalytic generation of ammonium formate species on the material's surface by hydrogenation of CO2. By altering the composition of the feed gas, a variety of benzofuran and quinoline derivatives can be selectively hydrogenated to fully or partially saturated products using a single catalyst.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Aleksandra Wandzilak, Katarzyna Grubel, Kazimer L. Skubi, Sean F. Mcwilliams, Dimitrios Bessas, Atanu Rana, Stefan Hugenbruch, Abhishek Dey, Patrick L. Holland, Serena Debeer
Summary: This study successfully elucidated the characteristics and mechanism of the intermediate species during the cleavage of the strong triple bond of N2 by Diketiminate-supported iron complexes, using a range of spectroscopic techniques and computational models.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Alexandre Genoux, Magnus Pauly, Conor L. Rooney, Chungseok Choi, Bo Shang, Scott McGuigan, Majed S. Fataftah, Yves Kayser, Simon C. B. Suhr, Serena Debeer, Hailiang Wang, Paul A. Maggard, Patrick L. Holland
Summary: Carbon nitride materials with stoichiometric iron sites having the same environment were synthesized and characterized. The material showed tetrahedral high-spin iron(II) sites throughout and exhibited excellent electrocatalytic activity for nitrate reduction to ammonia.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yang Liu, Sayanti Chatterjee, George E. Cutsail III, Sergey Peredkov, Sandeep K. Gupta, Sebastian Dechert, Serena DeBeer, Franc Meyer
Summary: This study reports the synthesis and characterization of [Cu-4(& mu;(4)-S)](n+) (n = 2, 2; n = 3, 3) clusters, which mimic the two active states of the Cu-Z* site during enzymatic N2O reduction. The structural and electronic properties of these clusters are elucidated using multiple methods. Preliminary reactivity studies demonstrate the nucleophilic character of the central & mu;(4)-S in the fully reduced 0-hole state.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Maria Alessandra Martini, Konstantin Bikbaev, Yunjie Pang, Christian Lorent, Charlotte Wiemann, Nina Breuer, Ingo Zebger, Serena DeBeer, Ingrid Span, Ragnar Bjornsson, James A. Birrell, Patricia Rodriguez-Macia
Summary: [FeFe] hydrogenase variants with a mutation in the proton transfer pathway can form two new active site states with a CN- ligand bound to the apical position of [2Fe](H). These states can be generated by either cannibalization from damaged [2Fe](H) subclusters or addition of exogenous CN-. This study provides the first detailed characterization of the interaction between exogenous CN- and [FeFe] hydrogenases.
Review
Chemistry, Physical
Andreas Erbe, Marc Frederic Tesch, Olaf Ruediger, Bernhard Kaiser, Serena DeBeer, Martin Rabe
Summary: Inspired by photosystem II, Mn oxide based electrocatalysts have been studied as catalysts for the electrochemical oxygen evolution reaction (OER). However, there are fundamental differences between biological OER catalyzed by CaMn4Ox and the requirements for an electrocatalyst in industrial applications. In this paper, the challenges and recent insights gained from in situ and operando methods, such as vibrational spectroscopy, absorption techniques, and operando X-ray spectroelectrochemistry, are discussed. Despite technical and Mn specific challenges, three key features, including structural disorder, Mn oxidation states between III and IV, and the appearance of layered birnessite phases, are common to most systems with significant OER activity.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Carli B. Kovel, Jonathan M. Darmon, S. Chantal E. Stieber, Gisselle Pombar, Tyler P. Pabst, Bastian Theis, Zoe R. Turner, Okten Ungor, Michael Shatruk, Serena DeBeer, Paul J. Chirik
Summary: This study describes the application of bimolecular reductive elimination to activate iron catalysts for alkene-diene cycloaddition. The synthesis, characterization, electronic structure determination, and solution stability of a family of pyridine(diimine) iron methyl complexes with different steric properties and electronic ground states are crucial to this approach. The investigations elucidate the electronic and steric features of the iron complexes that enable the unusual reductive elimination and precatalyst activation pathway.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Maria Chrysina, Maria Drosou, Rebeca G. Castillo, Michael Reus, Frank Neese, Vera Krewald, Dimitrios A. Pantazis, Serena Debeer
Summary: This research investigates the water splitting enzyme in Photosystem II using high-energy resolution fluorescence detected X-ray absorption spectroscopy. By combining quantum chemical calculations and experimental data analysis, the geometric and electronic structures of different catalytic intermediates are determined, ruling out the presence of peroxo or oxyl radicals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
