Article
Chemistry, Inorganic & Nuclear
Nathaniel L. Dominique, Ran Chen, Alyssa V. B. Santos, Shelby L. Strausser, Theodore Rauch, Chandler Q. Kotseos, William C. Boggess, Lasse Jensen, David M. Jenkins, Jon P. Camden
Summary: The exceptional stability of N-heterocyclic carbene (NHC) monolayers on gold surfaces and nanoparticles enables various applications. However, our understanding of NHC reactivity at surfaces is limited. In this study, the authors explore the use of established transmetalation reactions to create carbene functionalized gold surfaces. Experimental and theoretical results show that the reactivity can be tuned by changing the carbene structure and raise important questions.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Review
Chemistry, Inorganic & Nuclear
Pengcheng Gao, Michal Szostak
Summary: The catalytic addition of water to unsaturated C-C or C-N p bonds is an important and environmentally sustainable method for forming C-O bonds. Traditional acid-catalyzed hydration requires strong acids or toxic mercury salts, limiting its practical applications and posing safety and environmental concerns. Transition-metal-catalyzed hydration with NHC ligands has gained significant attention and has achieved major progress. This review provides a comprehensive overview of hydration reactions catalyzed by transition metal-NHC complexes and their applications in catalytic hydration.
COORDINATION CHEMISTRY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Arpan Das, Pallavi Sarkar, Subir Maji, Swapan K. Pati, Swadhin K. Mandal
Summary: A class of stable mesoionic N-heterocyclic imines (mNHIs) with highly polarized exocyclic imine moiety were synthesized. These mNHIs exhibit the highest basicity and donor ability among reported NHIs. The superior nucleophilicity of newly designed mNHIs was exploited to couple inert primary amides under reductive conditions and hetero-couple amide and amine using CO2. These catalytic transformations were used for the diversification of biologically active drug molecules under metal-free conditions. The mechanism was explored through control experiments and characterization of key intermediates using spectroscopic and crystallographic techniques.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Yi-Fan Zhang, Ya-Wen Zhang, Xin Li, Li-Ying Sun, Ying-Feng Han
Summary: Triarylborane-based discrete metal-carbene supramolecular cages [M-3(1)(2)](PF6)(3) (M = Ag, Au) were synthesized and characterized. The new hexacarbene assemblies show a significant solvatochromic effect in solvents of different polarity. Furthermore, the reversible fluoride binding property of [Au-3(1)(2)](PF6)(3) was investigated by UV-vis absorption and fluorescence titrations. This work holds promise for future developments in the area of highly emissive and stimulus-responsive NHC-metal assemblies.
CHEMICAL COMMUNICATIONS
(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)
Review
Chemistry, Inorganic & Nuclear
Hui Shen, Guolong Tian, Zhen Xu, Lingzheng Wang, Qingyuan Wu, Yuhao Zhang, Boon K. Teo, Nanfeng Zheng
Summary: This review provides an overview of the recent research advances in the use of N-heterocyclic carbenes (NHCs) as stabilizing agents and functionality modifiers for metal nanoparticles (NPs) and nanoclusters (NCs). It discusses the development of effective strategies for decorating metal NPs with NHCs and the improvements in catalytic performances achieved through NHC ligation on heterogeneous metal nanocatalysts. The review also highlights the synthesis of atomically precise NHC-stabilized metal NCs and their crystallographic structure analysis, which contribute to a better understanding of the carbene-metal interface at the atomic level. The review concludes with personal perspectives on the future development of this promising field.
COORDINATION CHEMISTRY REVIEWS
(2022)
Article
Nanoscience & Nanotechnology
Zichao Wei, Kayceety Mullaj, Aleisha Price, Kecheng Wei, Qiang Luo, Srinivas Thanneeru, Shouheng Sun, Jie He
Summary: This study presents a method for preparing metal nanoparticles (NPs) using polymer N-heterocyclic carbenes (NHCs) as surface ligands. The results demonstrate that polymer NHC-modified AgNPs exhibit excellent resistance to oxidative etching and enhanced peroxidase activity.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Review
Chemistry, Multidisciplinary
G. Mahantesh, Deepika Sharma, Rambabu Dandela, Vasudevan Dhayalan
Summary: This article reviews the synthesis and properties of N-heterocyclic olefins (NHO), as well as their applications as catalysts in organic synthesis. NHOs display electron-rich and polar characteristics, as well as strong basicity, making them highly promising catalysts with great chemical potential.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Ningning Xin, Xuemin Jing, Cheng-Gen Zhang, Xiaoxia Peng, Jing Liu, Qixing Wang, Wei Wang, Jian Cao, Minli Tao
Summary: Complex asymmetric synthesis can be achieved through the chiral induction of amino acids. Designing a new biomimetic catalytic system is of great significance for asymmetric synthesis. In this study, a composite of polyacrylonitrile fiber and metal-organic framework was prepared and characterized for the chiral synthesis of propargylamines. The supported catalyst showed high activity and excellent stereoselectivity in a three-component reaction. The confined microenvironment and the synergistic catalytic mechanism were investigated.
Review
Chemistry, Multidisciplinary
Changpeng Chen, Feng-Shou Liu, Michal Szostak
Summary: The discovery of NHCs as ancillary ligands has greatly improved catalytic processes, with BIAN-NHC ligands in particular showing enhanced reactivity due to combinations of electronic and steric properties. The development of BIAN-NHC ligands has led to major advancements in catalysis and offers a practical alternative to classical NHCs.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Analytical
Nathaniel L. Dominique, Shelby L. Strausser, Jacob E. Olson, William C. Boggess, David M. Jenkins, Jon P. Camden
Summary: This study investigates the stability and potential biological applications of N-heterocyclic carbene (NHC) self-assembled monolayers (SAMs) on gold surfaces, while utilizing laser desorption ionization mass spectrometry (LDI-MS) to explore the surface chemistry of NHC. By studying NHC-functionalized gold nanoparticles using LDI-MS, insights into the packing of NHC monolayers on gold surfaces and the stability of NHC ligands post-ligation were gained. The ability of LDI-MS to probe postsynthetic modifications of anchored NHCs, such as the reduction of nitro-NHC-AuNPs to amine-NHC-AuNPs, highlights its importance for current and future applications of NHC surfaces.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Leah K. Oliemuller, Curtis E. Moore, Christine M. Thomas
Summary: This study explores the bonding interactions and electronic structure of a diphosphine pincer ligand with a N-heterocyclic phosphenium/phosphido central moiety and nickel. The activation of O-H bonds across the Ni-PNHP bond and the successful installation of a P-H bond on the NHP unit are demonstrated.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Applied
Ming Huang, Jiahao Liu, Yinwu Li, Xiao-Bing Lan, Peifeng Su, Cunyuan Zhao, Zhuofeng Ke
Summary: N-heterocyclic carbenes (NHCs) are green and versatile ligands for transition metal (TM) catalysts. NHC-TM complexes based on noble metals Ir, Ru, and Os are widely studied, while NHC-based non-noble metals catalysts are still in the early stages for sustainable dehydrogenative catalysis using alcohols.
Article
Chemistry, Multidisciplinary
Md. Mahbubur Rahman, Guangrong Meng, Elwira Bisz, Blazej Dziuk, Roger Lalancette, Roman Szostak, Michal Szostak
Summary: ItBu is the most important and versatile N-alkyl N-heterocyclic carbene in organic synthesis and catalysis. In this study, we report the synthesis, characterization, and catalytic activity of ItOct (ItOctyl), higher homologues of ItBu. ItOct and SItOct, a new ligand class, have been commercialized to facilitate access for researchers in organic and inorganic synthesis. We demonstrate that the replacement of t-Bu side chain with t-Oct results in the highest steric volume of N-alkyl N-heterocyclic carbenes reported to date, while retaining important electronic properties. Coordination chemistry to various metals and beneficial effects on catalysis are also described.
Article
Chemistry, Multidisciplinary
Yilin Jiang, Yuan Yu, Xu Zhang, Micha Weinert, Xueling Song, Jing Ai, Lu Han, Honghan Fei
Summary: Ultrafine gold nanoclusters (Au-NCs) can be stabilized in a heterogeneous nucleation approach within an NHC-functionalized porous matrix, with tunable sizes based on MOF topology for superior photocatalytic CO2 reduction activity. Control experiments using different functionalized MOFs resulted in Au species aggregation. The synergistic catalytic effect of MOFs and Au-NCs through covalent bonding bridges was revealed in mechanistic studies, contributing to the excellent performance of the Au-NC@MOF composite.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
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)
Review
Chemistry, Multidisciplinary
Peter Bellotti, Huan-Ming Huang, Teresa Faber, Frank Glorius
Summary: The emergence of modern photocatalysis has revolutionized late-stage C-H functionalization, offering unprecedented regio- and chemoselectivities. This Review focuses on the strategies of small-molecule drugs, agrochemicals, and natural products, highlighting the main mechanistic scenarios and comparing established ionic chemistry and photocatalyzed radical-based manifolds. The authors aim to provide a comprehensive overview of the current state-of-the-art and address the challenges and future directions in this field.
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
Chemistry, Multidisciplinary
Fritz Paulus, Colin Stein, Corinna Heusel, Tobias J. Stoffels, Constantin G. Daniliuc, Frank Glorius
Summary: In this study, a novel three-component 1,2,5-trifunctionalization reaction driven by visible light energy transfer-catalysis was reported. Selective installation of three different functional groups was achieved in one step by utilizing imine-based bifunctional reagents and two distinct alkenes. Mechanistic studies and downstream modifications demonstrated the synthetic utility of the obtained products.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(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
Multidisciplinary Sciences
Huamin Wang, Huiling Shao, Ankita Das, Subhabrata Dutta, Hok Tsun Chan, Constantin Daniliuc, K. N. Houk, Frank Glorius
Summary: In this study, a photoinduced ring enlargement method of thiophenes was developed, which involves the insertion of bicyclo[1.1.0]butanes to form eight-membered bicyclic rings under mild conditions. The synthetic value, broad functional-group compatibility, and excellent chemo- and regioselectivity were demonstrated by scope evaluation and product derivatization. Experimental and computational studies suggested a photoredox-induced radical pathway.
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)
Article
Materials Science, Multidisciplinary
Robert Zielinski, Mowpriya Das, Canan Kosbab, Mike Thomas Nehring, Mario Daehne, Norbert Esser, Martin Franz, Frank Glorius
Summary: The adsorption behavior of cyclohexyl cyclic (alkyl)(amino)carbene molecules on a silicon surface is investigated, showing a self-limited, well ordered growth of a stable monolayer with large domains, which is surprising on semiconductors. Additionally, the surface defect density strongly influences the grade of ordering, as the initial adsorption takes place on a defect site.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Florenz Buss, Mowpriya Das, Daniel Janssen-Mueller, Alexander Sietmann, Ankita Das, Lukas F. B. Wilm, Matthias Freitag, Michael Seidl, Frank Glorius, Fabian Dielmann
Summary: This study reports the synthesis and properties of photoswitchable electron-rich phosphines containing N-heterocyclic imines. Heteronuclear NMR spectroscopy and UV/vis studies reveal reversible electrocyclic ring-closing and ring-opening reactions of the imine substituents upon exposure to UV and visible light. The photoisomerization alters the electron-donating ability of the phosphines by up to Delta TEP = 8 cm-1.
CHEMICAL COMMUNICATIONS
(2023)