Article
Chemistry, Medicinal
Tao Jia, Oumar Diane, Deepanjan Ghosh, Myriem Skander, Gaelle Fontaine, Pascal Retailleau, Joel Poupon, Jerome Bignon, Ytabelle Maga Moulai Siasia, Vincent Servajean, Nathalie Hue, Jean-Francois Betzer, Angela Marinetti, Sophie Bombard
Summary: This article introduces a new series of bimetallic platinum-(II) complexes with NHC-type bridging ligands, which exhibit cytotoxicity, cell accumulation, and DNA binding properties in cancerous cells. These complexes demonstrate significant radiosensitizing effects by inhibiting DNA repair mechanisms, leading to persistent accumulation of irradiation-induced DNA damages. This study provides the first in vitro evidence for the radiosensitizing properties of NHC-platinum complexes, suggesting their potential use in combined chemo-radiotherapy protocols.
JOURNAL OF MEDICINAL CHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Pui-Ki Wan, Ka-Chung Tong, Chun-Nam Lok, Chunlei Zhang, Xiao-Yong Chang, Kong-Hung Sze, Alice Sze Tsai Wong, Chi-Ming Che
Summary: A metal complex, Pt1a, has been found to interact with vimentin and inhibit tumor growth and metastasis, showing promise as an effective targeted chemotherapy for combating metastatic cancers.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Chemistry, Multidisciplinary
Rajendra S. Ghadwal
Summary: This review article aims to highlight recent advances in accessing stable iMICs, quantifying their properties, and exploring their applications in synthesis and catalysis. The synthetic viability and use of vicinal C4,C5-anionic dicarbenes (ADCs) based on a 1,3-imidazole framework are also presented. iMICs and ADCs have the potential to push the limit of classical NHCs by enabling access to conceptually new main-group heterocycles, radicals, molecular catalysts, ligand sets, and more.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Niklas F. Both, Anke Spannenberg, Haijun Jiao, Kathrin Junge, Matthias Beller
Summary: The use of bis(NHC) manganese(I) complexes 3 as catalysts for the hydrogenation of esters was investigated. Various aromatic and aliphatic esters were successfully hydrogenated at mild temperatures and low catalyst loadings using complexes 3 with KHBEt3 as additive, highlighting the efficiency of the novel catalytic system. Additionally, the versatility of the developed catalytic system was demonstrated by the hydrogenation of other substrate classes like ketones, nitriles, N-heteroarenes, and alkenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Jing Sun, Xiongkai Tang, Jiaqi Tang, Yuhao Zhang, Zilin Li, Hui Chaolumen, Shuo Guo, Hui Shen
Summary: Little progress has been made in developing alternative bottom-up synthetic strategies for N-heterocyclic carbene (NHC)-stabilized gold nanoclusters, but this study presents a simple and straightforward approach using imidazolium salts instead of free carbenes or NHC-coordinated gold complexes as precursors. The researchers successfully synthesized an NHC-stabilized Au13Br4 cluster using a one-pot and one-step process involving chemical reduction. This work not only expands the Au13 library with a new NHC-ligated superatom, but also provides a facile and reasonable method to explore similar analogues.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Hui Shen, Zhen Xu, Maryam Sabooni Asre Hazer, Qingyuan Wu, Jian Peng, Ruixuan Qin, Sami Malola, Boon K. Teo, Hannu Hakkinen, Nanfeng Zheng
Summary: Deciphering the atomic arrangement of hybrid surface ligands on metal nanoparticles is a key step towards understanding their complex geometrical and electronic structures, which can have potential bio-applications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Inorganic & Nuclear
Lingyu Kong, Yajie Chou, Muriel Albalat, Marion Jean, Nicolas Vanthuyne, Stephane Humbel, Paola Nava, Herve Clavier
Summary: The concept of atropisomeric N-heterocyclic carbene (NHC)-metal complexes with C-2-symmetry was extended to palladium-based complexes. Through a comprehensive study of NHC precursors and screening of various NHC ligands, the formation of meso complexes was successfully circumvented. Eight atropisomeric NHC-palladium complexes were prepared and obtained with high enantiopurities through efficient chiral HPLC resolution. These complexes demonstrated good activity in the intramolecular alpha-arylation of amides, leading to the isolation of cyclic products with excellent enantioselectivities (up to 98% ee).
DALTON TRANSACTIONS
(2023)
Review
Chemistry, Inorganic & Nuclear
Sai Zhao, Zhibing Yang, Guizhi Jiang, Sheng Huang, Mianli Bian, Yunlong Lu, Wukun Liu
Summary: NHCs have been introduced as a new platform for the development of anticancer metal complexes, with platinum NHC complexes showing comparable activities to cisplatin and exhibiting different mechanisms of action, including the induction of biochemical hallmarks of immunogenic cell death (ICD) as a type II ICD inducer. These features make them promising candidates in the field of anticancer research.
COORDINATION CHEMISTRY REVIEWS
(2021)
Review
Chemistry, Multidisciplinary
Sha Bai, Ying-Feng Han
Summary: N-heterocyclic carbenes (NHCs) have led to breakthroughs in transition-metal catalysis, main group chemistry, and organocatalysis. However, the chemistry of NHC-based metallosupramolecular assemblies is underdeveloped. This Account summarizes the development and applications of M-NHC chemistry toward supramolecular synthesis, including structural design, postassembly modification (PAM), and functional applications. The M-NHC-templated approaches have proven to be powerful methods for constructing diverse architectures with functional applications. Rating: 9/10
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Ichraf Slimani, Serap Sahin-Bolukbasi, Mustafa Ulu, Enes Evren, Nevin Gurbuz, Ilknur Ozdemir, Naceur Hamdi, Ismail Ozdemir
Summary: A series of rhodium(i) complexes with N-heterocyclic carbene ligands showed high in vitro cytotoxic activity against human cancer cells, with complex 2b exhibiting the most selective cytotoxic activity. These complexes demonstrated greater cytotoxicity against cancer cells compared to established anticancer agents cisplatin and 5-fluorouracil.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Louis Monsigny, Anna Kajetanowicz, Karol Grela
Summary: This review discusses a distinct class of ruthenium olefin metathesis catalysts with unsymmetrical N-heterocyclic carbene (uNHC) ligands, highlighting their advantages such as thermodynamic stability, chemical latency, selectivity, and compatibility with green solvents in specialized metathesis transformations. Despite being niche, uNHC complexes have the potential to be implemented in various industrial processes like valorization of Fischer-Tropsch olefin fractions, ethenolysis of renewable products, and modern pharmaceutical production.
Article
Chemistry, Multidisciplinary
Nedra Touj, Jerwin Jay Taping, Nikolay Tumanov, Johan Wouters, Lionel Delaude
Summary: The hydrolysis of imidazolinium chlorides occurs readily in a basic water/dichloromethane biphasic mixture at room temperature. Substrates with alkyl or aryl substituents on their nitrogen atoms led to high yields of gamma-aminoformamides. Bulky alkyl or aryl groups on the formamide moiety resulted in high stereoisomeric purity of the (E)-isomer. The presence of bulky aromatic substituents on the nitrogen atoms slowed down the hydrolysis of certain imidazolinium chlorides. The counteranion was found to have a critical influence on the reactivity of imidazolinium cations.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Jiaming Wang, Changgui Zhao, Jian Wang
Summary: Axial chirality is widely present in natural products and pharmaceutical compounds, and recent advances in using NHC organocatalysts have opened up new opportunities for the synthesis of enantioenriched axially chiral molecules. This perspective highlights the importance of NHCs in catalyzing the synthesis of axially chiral scaffolds and serves as a stepping stone for future investigations in this area.
Article
Chemistry, Multidisciplinary
Arpan Das, Soumi Chakraborty, Swadhin K. Mandal
Summary: Abnormal N-heterocyclic carbene (aNHC) based Ni(II) pi-allyl complexes (3 and 4) were synthesized from a Ni(0) precursor and characterized. The mechanism for the formation of Ni(II) eta(3)-allyl complexes from a Ni(0) precursor using a free abnormal N-heterocyclic carbene was elucidated. Exposure of complex 3 to O-2 gas under ambient pressure resulted in the activation of molecular oxygen to form a mu-hydroxo bridged Ni(II) dimer.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Liang Du, Neda Arabzadeh Nosratabad, Zhicheng Jin, Chengqi Zhang, Sisi Wang, Banghao Chen, Hedi Mattoussi
Summary: N-heterocyclic carbene (NHC)-modified ligands were tested for coordinating and stabilizing luminescent CdSe-ZnS core-shell quantum dots (QDs) in hydrophilic media. The coordination of NHC ligands onto QDs was found to be rapid and effective, leading to enhanced long-term colloidal stability and changes in optical and spectroscopic properties of the nanocrystals, including red-shift in absorption and fluorescence spectra and intensity changes under different storage conditions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
Yannick Geiger, Stephane Bellemin-Laponnaz
Summary: Non-linear effects between enantiomeric excesses of ligand and product are common in asymmetric catalysis, and they are useful tools for mechanistic investigations. This study shows that catalyst precipitation affects the shape and amplitude of non-linear effects curves, and it also observes several peculiar features. Overall, this research provides a better understanding of chiral catalytic systems.
Article
Chemistry, Physical
Anna Bonfiglio, Pei-Wan Hsiao, Yin Chen, Christophe Gourlaouen, Quentin Marchand, Vincent Cesar, Stephane Bellemin-Laponnaz, Yun-Xin Wang, Chin-Wei Lu, Chantal Daniel, Federico Polo, Hai-Ching Su, Matteo Mauro
Summary: This study presents a class of bright heterobimetallic emitters with enhanced fluorescence efficiency and radiative rate constant. The application of these bimetallic complexes in light-emitting electrochemical cells achieves high external quantum efficiency.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Julien Egly, Weighang Chen, Aline Maisse-Francois, Stephane Bellemin-Laponnaz, Thierry Achard
Summary: Amide synthesis is a crucial transformation in chemistry and biology. N-heterocyclic carbene-based ruthenium catalyst systems have been proven to be active for direct synthesis of amides. In this study, a series of Ru complexes with thioether-functionalized N-heterocyclic carbene ligands were prepared and applied to the amidation reaction, resulting in high conversions but moderate yields.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Damien Bissessar, Julien Egly, Thierry Achard, Pascal Steffanut, Matteo Mauro, Stephane Bellemin-Laponnaz
Summary: A tetranuclear copper-iodide cluster has been identified as a stable precursor for further post-functionalization, allowing the direct functionalization of alkenes and providing access to a wide range of luminescent copper cubane complexes, including the first example of water-soluble luminescent cubane copper iodide.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Yaidel Toledo-Gonzalez, Jean-Marc Sotiropoulos, Diane Becart, Gilles Guichard, Philippe Carbonniere
Summary: Peptides and foldamers have shown high reactivity and selectivity as chiral catalysts for transformations. Using density functional theory, this study analyzed the interaction between substrates and catalysts, and found that electrostatic interactions play a major role in molecular recognition and catalytic properties.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Thibault Thierry, Yannick Geiger, Stephane Bellemin-Laponnaz
Summary: Phenomena related to asymmetric amplification are crucial for understanding the emergence of homochirality in life. This study focuses on asymmetric catalysis and investigates non-linear effects in chiral amplification. The authors provide experimental evidence of a new nonlinear hyperpositive effect in enantioselective zinc-catalyzed alkylation. Their research also reveals a mechanism involving both monomeric and dimeric complexes that contribute to different enantioselectivities.
Article
Polymer Science
Mohamed Samir Zaky, Anne-Laure Wirotius, Olivier Coulembier, Gilles Guichard, Daniel Taton
Summary: Stereochemical control is a key strategy in polymer chemistry for achieving semicrystalline engineering plastics. However, the study of stereoselective ring-opening polymerization using chiral organocatalysts is relatively under-explored. This research demonstrates that a commercially available chiral thiourea or its urea homologue, when used in conjunction with an appropriately selected N-heterocyclic carbene, can trigger the stereoselective ring-opening polymerization of lactide at room temperature in toluene, achieving high stereoselectivity and catalytic activity.
Article
Engineering, Biomedical
Conor McCartin, Juliette Blumberger, Candice Dussouillez, Patricia Fernandez de Larrinoa, Monique Dontenwill, Christel Herold-Mende, Philippe Lavalle, Beatrice Heurtault, Stephane Bellemin-Laponnaz, Sylvie Fournel, Antoine Kichler
Summary: Cationic polymers like polyethylenimine (PEI) have been widely used as gene delivery agents and drug delivery agents. Recent studies have shown that certain polycations have higher toxicity towards cancer stem cells (CSCs) than differentiated tumor cells. Since CSCs play a critical role in cancer drug resistance, tumor recurrence, and poor clinical prognosis, it is important to investigate compounds that can target and eliminate these cells.
JOURNAL OF FUNCTIONAL BIOMATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Nagendar Pendem, Yella-Reddy Nelli, Leonie Cussol, Claude Didierjean, Brice Kauffmann, Christel Dolain, Gilles Guichard
Summary: Oligomers with a helix-turn-helix super-secondary structure were prepared by covalently bridging aliphatic oligourea foldamer helices with either rigid aromatic or flexible aliphatic spacers. The relative orientation of the helices in these dimers was studied using high-resolution X-ray diffraction analysis. Racemic crystallography was employed in some cases to facilitate crystallization and structure determination. All structures were solved using direct methods. Well-defined parallel helical hairpin motifs were observed in all cases when 4,4'-methylene diphenyl diisocyanate was used as a dimerizing agent, regardless of the primary sequence and chain length.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Polymer Science
Mohamed Samir Zaky, Gilles Guichard, Daniel Taton
Summary: This study investigates the stereoselective ring-opening polymerization (ROP) of racemic lactide (rac-LA) using a series of chiral amino(thio)ureas and phosphazene organic bases. The chiral binary organocatalytic pairs showed fast and highly selective ROP of rac-LA, resulting in semicrystalline and metal-free stereoblock-like materials based on polylactide (PLA). The reaction rates and stereocontrol were found to be influenced by the components of the pairs and the phosphazene bases used.
Article
Chemistry, Physical
Jordi Vila, Miquel Sola, Thierry Achard, Stephane Bellemin-Laponnaz, Anna Pla-Quintana, Anna Roglans
Summary: This article describes the [2 + 2 + 2] cycloaddition of 1,5-bisallenes and alkynes under the catalysis of Rh(I) with hemilabile thioether-functionalized N-heterocyclic carbene ligands. This method effectively provides access to different trans-5,6-fused bicyclic systems with two exocyclic double bonds in the cyclohexene ring. The complete mechanism of this transformation as well as the preference for the trans-fusion over the cis-fusion has been rationalized by density functional theory calculations.
Article
Multidisciplinary Sciences
Damien Bissessar, Thibault Thierry, Julien Egly, Valerio Giuso, Thierry Achard, Pascal Steffanut, Matteo Mauro, Stephane Bellemin-Laponnaz
Summary: We synthesized and studied three new copper halide derivatives 2a-c, which are tetranuclear copper-iodide clusters consisting of a cubane-like {Cu4I4} motif and phosphine ligands P. They differ in the type of phosphines used as ligands: a monophosphine with a single pendant ester unit (2a), two pendant ester units (2b), and a diphosphine containing two esters in the linker (2c). The complexes displayed intense and long-lived photoluminescence in the orange region with PLQY values of 0.43-0.84 at room temperature, mainly associated with a (CC)-C-3 excited state with mixed (XMCT)-X-3 character.
Article
Chemistry, Applied
Luc Schuler, Danny Zust, Georges Dahm, Fabienne Clabots
Summary: The aim of this study was to analyze the presence of nickel in non-animal origin food and beverages sold in Luxembourg, in order to determine the population's exposure to this contaminant. The results showed high concentrations of nickel in cashew nuts, walnuts, hemp and sunflower seeds, dried peas, oregano, and cocoa powder. Monitoring contaminants in food helps identify contributors to nickel exposure, potentially leading to the establishment of official maximum levels in European legislation and enhancing consumer protection.
FOOD ADDITIVES & CONTAMINANTS PART B-SURVEILLANCE
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
T. Thibault, M. Gurung, C. Leuvrey, A. Boos, P. Ronot, I. El Masoudi, P. Hoerner, S. Bellemin-Laponnaz
Summary: This study found that lead-containing gloves may present a risk of metal leaching when in contact with sweat, and the level of lead leaching depends on the acidity of the sweat and the duration of contact. Gloves with a protective lining reduce the transfer of lead into sweat, but significant levels of lead are still present.
Article
Chemistry, Multidisciplinary
Aline Delamare, Guillaume Naulet, Brice Kauffmann, Gilles Guichard, Guillaume Compain
Summary: The hexafluoroisobutyl group is a commonly found hydrophobic group in drugs, and its introduction can provide new advantages to compounds. However, the lack of a general and practical synthetic methodology has hindered the exploration of this modification. In this study, the first general method for introducing the hexafluoroisobutyl group into various compounds was reported. This method overcomes the usual fluoride beta-elimination observed with other CF3-vinyl groups, and it has been successfully applied to the multigram-scale synthesis of enantiopure (S)-5,5,5,5',5',5'-hexafluoroleucine.
