Article
Chemistry, Inorganic & Nuclear
Anastasia Yu. Gitlina, Farzaneh Fadaei-Tirani, Kay Severin
Summary: The isomerization of iridium(iii) complexes with metalated N-heterocyclic carbene (NHC) ligands was investigated. The fac isomers of complexes with 1-phenyl-3-methylbenzimidazolin-2-ylidene or 1-phenyl-3-benzylbenzimidazolin-2-ylidene ligands can be cleanly transformed into the mer isomers using HNTf2 and then NEt3. However, an iridium complex with a 1-phenyl-1,2,4-triazolo[4,3-f]phenanthridine-based carbene ligand could not undergo isomerization under similar conditions.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Rahat Gupta, Priya Sahni, Salil K. Jana, Anshul Negi, Amlan K. Pal
Summary: In this study, two novel deep-blue Ir-NHC emitters were synthesized with strategically designed pro-carbenic imidazolium ligands incorporating a heavy bromine atom. These emitters exhibited enhanced emission properties in both solution and film forms, with a 15 times higher photoluminescence quantum yield compared to benchmark complexes.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Kyle R. Penn, Evan J. Anders, Vincent N. G. Lindsay
Summary: This method improves the conversion rates of synthesizing bis-(imidazolium) dichloride salts by using excess CH2Cl2 and DMSO in the reaction. Additionally, it can also be applied to the formation of bis(pyridinium) dichloride salts and metal-bis(NHC) complexes directly from imidazoles.
Article
Chemistry, Inorganic & Nuclear
Nida Shahid, Rahul Kumar Singh, Navdeep Srivastava, Amrendra K. K. Singh
Summary: A series of Ru(III)-NHC complexes have been prepared through a base-free route. These air and moisture-stable complexes, which represent rare examples of paramagnetic Ru(III)-NHC complexes, were shown to be excellent metal precursors for the synthesis of new Ru(II)-NHC complexes. This work allows easy access to new Ru-NHC complexes for the study of new properties and novel applications.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Lukas Tendera, Moritz Helm, Mirjam J. Krahfuss, Maximilian W. Kuntze-Fechner, Udo Radius
Summary: This study investigates the effects of two different NHC ligands in complexes [Ni(NHC)(2)] and their behavior towards alkynes. Complex 2 demonstrated efficient catalytic activity for the cyclotrimerization of various alkynes at ambient conditions, while complex 1(Me) showed lower catalytic performance. The higher stability of N-alkyl substituted NHC complex is attributed to better electron transfer and enhanced backbonding.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Review
Chemistry, Multidisciplinary
Zhifeng Zhang, Yang Chen, Xiao Gu, Chun-Yu Ho
Summary: Well-controlled olefin insertion is crucial for achieving efficient and selective bulk and fine-chemical synthesis. Nickel catalysts, particularly those based on N-heterocyclic carbene (NHC) ligands, have shown great potential in meeting the diverse demands of olefin codimerization and hydrovinylation. These catalysts offer a high level of control and have the ability to unite previously unreactive substrate pairs, leading to the synthesis of complex and structurally diverse compounds.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Estefan van Vuuren, Frederick P. Malan, Marile Landman
Summary: Novel Ir-based NHC complexes (1-4) were synthesized using N-alkenyl functionalized imidazolium salts with Ir(iii) precursors. Complex 1 represents an unprecedented cyclometallated complex, which is the first and only example in literature, to our knowledge, of a non-aromatic C(sp(2))-H activation leading to a C(sp(3))-Ir cyclometallated product. Subsequent reactions with a range of imidazolium salts featuring different N-pendant arms were performed, including alkenyl and benzyl tethers. Selectivity with regards to cyclometallation behavior of the iridium center was observed in preference for a benzyl cyclometallated product over alkenyl cyclometallation. Benzyl-containing products proved most promising as active catalysts in both the hydrosilylation of internal alkynes with a conversion of up to 59% after 1 hour, as well as the transfer hydrogenation of ketone and aldehyde substrates with conversions of up to 100% after 18 hours using catalyst loadings of 4 and 1 mol% respectively.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Raill R. Quinonez-Lopez, Sara A. Cortes-Llamas, J. Roberto Estrada-Flores, Jose G. Alvarado- Rodriguez, Oscar Blanco-Alonso, A. Aaron Peregrina-Lucano, Elvia Becerra-Martinez, I. Idalia Rangel-Salas
Summary: Heteroleptic [RhIIICp*(NHC)] and [IrIIICp*(NHC)] complexes with a N-amino acid functionality derived from imidazolium salts were synthesized and characterized. The structure of [RhCp*{kappa 2(C,O)-NHC}Cl] complex 3f was discussed as a pair of diastereomers. The catalysts showed good yields for the transfer hydrogenation of ketones in basic propan-2-ol, and a chromatographic method for measuring compounds in the reaction was validated. These Rh and Ir complexes provide a new approach in developing catalysts based on classical NHC precursors.
Review
Environmental Sciences
Mathurin Francois, Kuen-Song Lin, Nova Rachmadona, Kuan Shiong Khoo
Summary: The use of fossil fuels, GHG emissions, and waste are urgent problems for the environment and public health. Among various chemical activating agents, FeCl3 is the most cost-effective and environmentally friendly one to enhance AD and improve biomethane quality and quantity. FeCl3 can increase the BET surface area of biochar and effectively remove contaminants in wastewater and biogas. However, further research is needed to investigate its ability in removing water vapor and carbon dioxide during biogas production.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Pharmacology & Pharmacy
Ines Marmol, Javier Quero, Paula Azcarate, Elena Atrian-Blasco, Carla Ramos, Joana Santos, Maria Concepcion Gimeno, Maria Jesus Rodriguez-Yoldi, Elena Cerrada
Summary: This paper describes the synthesis of new N-heterocyclic carbene (NHC) gold(I) derivatives and their screening for antimicrobial and anticancer activities. The compounds showed greater activity against bacteria than against colon cancer cells. The mechanism of action of one of the compounds, 1b, was evaluated and it was found to inhibit dihydrofolate reductase (DHFR) activity in E. coli cells and cause structural changes in the bacteria.
Article
Chemistry, Multidisciplinary
Luis Angel Turcio-Garcia, Hugo Valdes, Antonino Arenaza-Corona, Simon Hernandez-Ortega, David Morales-Morales
Summary: A series of selenourea compounds with fluorinated fragments were synthesized and their Se-77 NMR chemical shifts were studied. The presence of more fluorine atoms in the structure caused a downfield shift of the Se-77 signal, indicating higher pi-acidity in the N-heterocycle. The position of the fluorine atom also influenced the chemical shift, with the 3-position showing the highest downfield shift.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Matteo Bevilacqua, Marco Roverso, Sara Bogialli, Claudia Graiff, Andrea Biffis
Summary: We report a new method for synthesizing phosphine (PR3) and di-N-heterocyclic carbene (di-NHC) ligand stabilized molecular gold nanoclusters (AuNCs). The reaction of di-NHC gold(I) complexes with [Au11(PPh3)8Cl2]Cl clusters results in the formation of three new classes of AuNCs through a controllable reaction sequence. The electronic and steric properties of the di-NHC ligand affect the product distribution, leading to the isolation and characterization of different clusters. One of the characterized clusters shows strong emission in solution.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Shuai Zhang, Yifei Zhao, Yayun Zhou, Man Li, Wei Wang, Hong Ming, Xiping Jing, Shi Ye
Summary: The study investigates the dipole-dipole interaction between head groups and Mn blocks on the crystalline structures and luminescent properties of two 0D Mn hybrids. The efficient Forster Resonance Energy Transfer (FRET) in [C16Py](2)MnBr4 is attributed to parallel-oriented dipoles, while the absence of FRET in [C16mim](2)MnBr4 is due to perpendicular-oriented dipoles. This work provides insights into the influence of organic spacers on the geometry and dipole interaction of Mn polyhedron in the hybrids, which could be beneficial for future optical regulations and structural design.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Rong-Jian Li, Yang Wang, Yan Jin, Wei Deng, Zhen-Jiang Liu, Zi-Jian Yao
Summary: Neutral C,C-chelate half-sandwich iridium(iii) complexes with NHC ligands containing pendant aromatic rings show excellent catalytic activity for acceptorless dehydrogenation reactions and transfer hydrogenation reactions of alcohols and ketones. These complexes are efficient in producing aldehydes from primary alcohols and alcohols from ketones and aldehydes under mild conditions. The exact structure and bonding mode of these NHC-based iridium complexes have been identified using various spectroscopic methods and single crystal X-ray analysis.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Construction & Building Technology
Huanchun Cai, Zijian Song, Ming-Zhi Guo, Linhua Jiang, Hongqiang Chu
Summary: This study investigated the influence of ultrasound on chloride release from cementitious materials. The results showed that ultrasound power enhanced both the equilibrium point and release rate of chloride, while ultrasound frequency mainly promoted the release rate. Kinetics analysis demonstrated that the chemical reaction step controlled chloride release, and its dominance was not weakened by ultrasound. Interestingly, physically bound chlorides decomposed faster than chemically bound ones after ultrasound irradiation. Overall, the findings clearly demonstrated the beneficial effect of ultrasonic waves on improving chloride release from cementitious materials.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Chemistry, Applied
Hawraa S. Al-Buthabhak, Valerio Falasca, Yu Yu, Alexandre N. Sobolev, Brian W. Skelton, Stephen A. Moggach, Vito Ferro, Hani Al-Salami, Murray Baker
Summary: Novel complexes of (NHC)Au(SCOR) were synthesised and characterised using spectroscopic techniques and X-ray diffraction. The results indicated that thiocarboxylate ligands have comparable electron donor ability with NHCs. The complexes were stable at room temperature in solid state but showed disproportionation reactions in solution. The thiocarboxylate ligand in (NHC)Au(SCOR) underwent rapid exchange with other thiocarboxylate or thiolate ligands. Furthermore, these complexes exhibited toxicity against cisplatin-resistant ovarian cancer cells.
APPLIED ORGANOMETALLIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Max Roemer, Angus Gillespie, David Jago, David Costa-Milan, Jehan Alqahtani, Juan Hurtado-Gallego, Hatef Sadeghi, Colin J. Lambert, Peter R. Spackman, Alexandre N. Sobolev, Brian W. Skelton, Arnaud Grosjean, Mark Walkey, Sven Kampmann, Andrea Vezzoli, Peter V. Simpson, Massimiliano Massi, Inco Planje, Gabino Rubio-Bollinger, Nicolas Agrait, Simon J. Higgins, Sara Sangtarash, Matthew J. Piggott, Richard J. Nichols, George A. Koutsantonis
Summary: This paper describes the synthesis methods of several functionalized dihydropyrene (DHP) molecular switches with different substitution patterns and demonstrates their molecular properties and switching capabilities through experiments. The performance of DHPs was assessed by light irradiation experiments, spectroelectrochemistry, and cyclic voltammetry. The molecular structures were elucidated by X-ray single-crystal diffraction. Charge-transport behavior was evaluated by combining density functional theory (DFT) calculations and single-molecule scanning tunneling microscope (STM) measurements.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Crystallography
Monica Bernard Tan, Alexandre N. N. Sobolev, Colin L. L. Raston, Scott J. J. Dalgarno, Irene Ling
Summary: This study examines the single crystal structures of two bulky phosphonium compounds and investigates their self-assembly behavior. It is found that the organic cations form stable stacked columns with voids occupied by anions or solvent molecules. The analysis suggests that hydrogen bonding plays a dominant role in stabilizing the self-assembly.
Article
Crystallography
Olga Yu Vassilyeva, Elena A. Buvaylo, Vladimir N. Kokozay, Alexandre N. Sobolev
Summary: The hybrid salt crystallizes in the monoclinic space group with an Sn0.5Cl3 fragment and an organic cation. The cation has coplanar rings and expected bond lengths, while the Cl-Sn-Cl angles in the dianion approach 90 degrees. The crystal structure is formed by pi-stacked chains of cations and loosely packed dianions.
ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS
(2023)
Article
Crystallography
Olga Yu. Vassilyeva, Elena A. Buvaylo, Oksana V. Nesterova, Alexandre N. Sobolev, Dmytro S. Nesterov
Summary: The organic-inorganic lead halide hybrids, consisting of semiconducting perovskite components and organic modules, have shown great potential for optoelectronic applications. In this study, new one-dimensional lead halide hybrid perovskites were successfully prepared and characterized. The results reveal that these materials have relatively small optical band gaps.
Article
Crystallography
Lioubov I. Semenova, Irene Ling, Alexandre N. Sobolev
Summary: Single-crystal X-ray structure determinations were conducted on four lanthanide complexes, revealing the dominant influence of ordered binding interactions with aza-aromatic units in all four complexes. The complex 1 also showed additional interactions that may contribute to the overall chiral nature of the crystal. Detailed analysis of these weak intermolecular interactions was performed using Hirshfeld surface analysis.
Article
Crystallography
Olga Yu Vassilyeva, Elena A. Buvaylo, Vladimir N. Kokozay, Brian W. Skelton
Summary: This article investigates a new type of 0-D hybrid salt, composed of discrete organic cations and tetrachloridomanganate(II) anions. The crystal structure shows that the fused heterocyclic rings in the organic cations almost coplanar and have expected bond lengths. The tetrahedral MnCl4(2-) anion is slightly distorted with varying bond lengths and angles. In the crystal, the compound exhibits a pseudolayered arrangement with separate organic and inorganic sheets stacked alternately. The analysis also reveals the presence of non-conventional C-H center dot center dot center dot Cl-Mn hydrogen bonding in the crystal packing.
ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
David Jago, David C. Milan, Alexandre N. Sobolev, Simon J. Higgins, Andrea Vezzoli, Richard J. Nichols, George A. Koutsantonis
Summary: The modification of conjugated organic compounds with organometallic moieties allows the modulation of their properties and enables various material applications. In this study, organometallic complexes modified with an indole ligand were prepared and characterized. The indole ligand showed Lewis base properties and could extract a proton from a vinylidene intermediate and coordinate to CuI. However, molecular junction formation was not observed in wire-like compounds, possibly due to the binding characteristics of the indole groups used.
AUSTRALIAN JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Paul S. Donnelly, Jack M. Harrowfield, George A. Koutsantonis, Nigel A. Lengkeek, Irene Ling, Gareth L. Nealon, Lachlan E. McInnes, Brian W. Skelton, Alexandre N. Sobolev, Allan H. White, Jonathan M. White
Summary: Single-crystal X-ray diffraction studies have confirmed that the form of the metal ion/sarcophagine unit is unique for each metal, and the size and shape of the substituent on the complex do not differ significantly from those of the isolated components. However, reactivity differs when the substituent contains reactive sites. The use of Hirshfeld surface analysis helps explain these differences. The complexes act as kinetically inert regioselective protecting groups.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
David Jago, Chongguang Liu, Abdalghani H. S. Daaoub, Emma Gaschk, Mark C. Walkey, Thea Pulbrook, Xiaohang Qiao, Alexandre N. Sobolev, Stephen A. Moggach, David Costa-Milan, Simon J. Higgins, Matthew J. Piggott, Hatef Sadeghi, Richard J. Nichols, Sara Sangtarash, Andrea Vezzoli, George A. Koutsantonis
Summary: The design of molecular switches is crucial for the development of molecular electronics. This study describes the use of spiropyrans in single-molecule devices and introduces an orthogonal T-shaped approach for incorporating spiropyran moieties, which leads to higher conducting states. Photochemical isomerization to merocyanine increases the conductance of the molecules.
Article
Crystallography
Irene Ling, Alexandre N. Sobolev, Chang Hoong Chek, Jack M. Harrowfield
Summary: The crystal structure of tetra-n-butylammonium perchlorate has been determined using single-crystal X-ray diffraction. The structure features columns of perchlorate anions surrounded by tetra-n-butylammonium cations, forming nanotubular entities.
Article
Chemistry, Inorganic & Nuclear
Angus A. Gillespie, Max Roemer, David Jago, Alexandre N. Sobolev, Gareth L. Nealon, Peter R. Spackman, Stephen A. Moggach, George A. Koutsantonis
Summary: Functionalising organic molecular photoswitches with metal complexes can alter and enhance their switching states, providing a promising basis for innovative smart molecular materials and molecular electronic devices. In this study, we synthesized and characterized mono- and bimetallic half-sandwich ruthenium and iron complexes functionalised with alkynyl dihydropyrenes (DHP). The introduction of the metal alkynyl moiety allowed access to additional redox and protonation states. However, the presence of an additional metal alkynyl moiety inhibited observable photochromic switching.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Wei-Jiun Yeoh, Alexandre N. Sobolev, Martin J. Paterson, Scott J. Dalgarno, Irene Ling
Summary: Naphthalene derived compounds have significant importance in medicinal chemistry due to their interesting biological activities. This study investigates the molecular and structural characteristics of three naphthalene-derived dications using X-ray crystallography and Hirshfeld surface analysis. The research explores the contributions of various intermolecular contacts to the crystal packing and analyzes the factors influencing these differences.
Article
Chemistry, Multidisciplinary
Irene Ling, Cameron L. Campbell, Alexandre N. Sobolev, Scott J. Dalgarno
Summary: This study reports four ternary multi-component crystal structures containing water-soluble p-sulfonatocalix[4]arene anion as the cavitand, along with different types of positively charged guest molecules and aquated lanthanide(iii) ions (Gd(iii) or Ce(iii)). Crystallographic analysis reveals that all positively charged imidazole rings are encapsulated by p-sulfonatocalix[4]arene. A molecular capsule is formed in all structures, regardless of the type of guest species.
Article
Crystallography
Olga Yu Vassilyeva, Elena A. Buvaylo, Vladimir N. Kokozay, Brian W. Skelton
Summary: Three isomorphous 0-D hybrid salts consisting of 2-methylimidazo[1,5-a]pyridinium cations and mixed-halide tetrahalometallate anions have been reported. The structures exhibit a pseudo-layered arrangement with alternating organic and inorganic layers. C-H center dot center dot center dot X-M (X = Cl, Br, I) contacts provide additional structural stabilization.
ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS
(2022)
