Article
Chemistry, Organic
Jens Lindman, Anubha Yadav, Johan Gising, Mats Larhed
Summary: This paper reports a palladium(0)-catalyzed aminocarbonylation reaction using molybdenum hexacarbonyl as a carbon monoxide precursor for the synthesis of N-capped amino acids using aryl and heteroaryl bromides and triflates. The carbon monoxide is generated ex situ and utilized in the palladium-catalyzed reaction chamber. By utilizing this method, 21 N-capped amino acids were synthesized using two series of aryl bromides and aryl triflates with isolated yields between 40% and 91%.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Ruiting Yang, Qiumin Xie, Qian Yan, Xiuli Zhang, Bao Gao
Summary: A novel approach for synthesizing thioesters using S-aryl thioformates as sources was reported, showing smooth transfer of the thioester moiety to aryl iodides. The reaction can be conducted at ambient temperature and tolerates a variety of substrates, with moderate to excellent yields. The scalability of this method was demonstrated through a gram-scale reaction with little change in chemical yield.
Article
Chemistry, Organic
Ruiting Yang, Qiumin Xie, Qian Yan, Xiuli Zhang, Bao Gao
Summary: A novel method for synthesizing thioesters using S-aryl thioformates as sources has been reported. The reaction achieved desirable yields of thioesters with various substrates under mild conditions. Gram-scale synthesis was also successful using this method.
Article
Chemistry, Organic
Gajanan K. Rathod, Rahul Jain
Summary: We report the palladium-catalyzed aminocarbonylation of (hetero)aryl iodides using alpha-amino acid esters as nucleophiles. The synthesized N-capped alpha-amino acids are important building blocks in biology. The reaction is carried out under mild conditions, yielding products with high enantioselectivity in a short period of time. Additionally, regioselective carbonylation of histidine is achieved for the first time.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Ning Liu, Xianqing Wu, Chenglong Wang, Jingping Qu, Yifeng Chen
Summary: A nickel-catalyzed alkoxycarbonylation reaction of aromatic iodides with alcohols under atmospheric pressure of carbon monoxide is demonstrated. This operationally simple protocol enables the facile synthesis of (hetero)aromatic esters, showing broad substrate scope and excellent functional group tolerance. Various primary and secondary aliphatic alcohols as well as phenols are suitable for this transformation.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Yunhui Feng, Hang Luo, Fangnian Yu, Qian Liao, Luqing Lin
Summary: Here, we present a visible-light-promoted single nickel catalysis for achieving various C-N couplings of aryl chlorides/bromides and diverse N-nucleophiles using sodium iodide as the activator. The single nickel catalyst plays a dual role in halogen exchange and C-N coupling, which are crucial for obtaining the desired coupling products. This catalytic process eliminates the need for an exogenous photocatalyst and offers a sustainable and efficient approach for mild C-N coupling. Experimental studies, along with UV-vis and NMR analyses, demonstrate that the halogen exchange between both Ni-II and Ni-III-halide complexes and the iodide anion is a significant process in the formation of coupling products.
Article
Chemistry, Organic
Bill J. Motsch, Jasjit Y. Kaur, Sarah E. Wengryniuk
Summary: Here, a metal-free oxidative C-H amination of arenes is described using a heterocyclic group transfer reaction from an I(III) N-HVI reagent. N-heterocycles act as oxidatively masked amine nucleophiles, and the resulting N-arylpyridinium salts are inert to further oxidation. The reaction occurs under mild conditions, and mechanistic studies suggest the presence of an arene radical cation intermediate. Derivatizations of the resulting pyridinium salts to various aryl amine scaffolds are demonstrated.
Article
Chemistry, Organic
Bill J. Motsch, Jasjit Y. Kaur, Sarah E. Wengryniuk
Summary: In this paper, a metal-free oxidative C-H amination of arenes is reported via a heterocyclic group transfer reaction from an I(III) N-HVI reagent. N-heterocycles are used as oxidatively masked amine nucleophiles, and the resulting N-arylpyridinium salts are inert to further oxidation. The reaction proceeds under mild conditions, and mechanistic studies suggest the intermediacy of an arene radical cation. Derivatizations of the resulting pyridinium salts to diverse aryl amine scaffolds are demonstrated.
Article
Chemistry, Organic
Dan Li, Li Wei, Wenfang Xiong, Huanfeng Jiang, Chaorong Qi
Summary: A palladium-catalyzed reductive formylation of aryl iodides with carbon dioxide as the carbonyl source was achieved using Pd(PCy3)2Cl2 and di-2-pyridyl ketone as the catalyst and phenylsilane as the reductive reagent under mild reaction conditions. The reaction provided a variety of aromatic aldehydes in moderate to excellent yields and exhibited good substrate scope, functional group tolerance, and easy operation.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Xueling Liu, Tongshun An, Zhiping Yin, Wenzhou Zhang
Summary: A new palladium-catalyzed reductive double carbonylation of nitroarenes with aryl halides has been developed for the synthesis of benzoxazin-4-ones. This method utilizes Mo(CO)(6) as a reductant and solid carbonyl sources, and can produce benzoxazin-4-one derivatives in moderate to good yields. Importantly, it avoids the use of toxic CO gas and is applicable for late-stage modification of estrone.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Guo-Qin Hu, Wen-Yan Zhang, Yong-Xin Liu, Jing-Hui Liu, Bin Zhao
Summary: Here, we present a decarboxylative thiocarbonylation method of aryl and alkenyl sulfonium salts using oxalic acid monothioethers (OAMs) under visible light-accelerated palladium catalysis. The reaction demonstrates a new application of visible light-accelerated palladium catalysis in catalytic decarboxylative cross-couplings, allowing the synthesis of different types of thioester compounds. Both sulfonium salts and OAMs are easily accessible and stored reagents.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Laszlo Kollar, Attila Takacs, Csilla Molnar, Andrew Kovacs, Laszlo T. Mika, Peter Pongracz
Summary: In this study, palladium-catalyzed amino- and alkoxycarbonylation reactions of aryl iodides were investigated using aliphatic heterobifunctional N,O-nucleophiles. Selective synthesis of amide alcohols and amide esters was achieved by adjusting the base and substrate ratio. The effect of iodobenzene substituents on product selectivity was studied and yielded surprising results. Various heteroaromatic substrates and related nucleophiles were tested under optimized conditions, resulting in moderate to good yields of the target compounds. The reactions of serinol and 1,3-diamino-2-propanol as model trifunctional compounds showed high chemoselectivity towards amide ester products. A rational catalytic cycle was proposed based on the coordinative properties of the applied nucleophiles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Weiling Chiu, Ben E. Nadeau, Brian O. Patrick, Jennifer A. Love
Summary: In this study, the mechanism of Ni-catalysed trifluoromethylthiolation of aryl chlorides using AgSCF3 was investigated. Various IPr Ni-II complexes were synthesized and their reactivity with AgSCF3 was studied. The results showed that CuSCF3 behaves similarly to AgSCF3, while NMe4SCF3 leads to a major side reaction forming a nickel fluoride complex. NMR kinetic studies revealed no significant correlation between the substituents and the formation of products. Cyclic voltammetry and solvent polarity were found to affect the formation rate of the product. The evidence suggests an inner-sphere electron transfer mechanism.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Organic
Francesco Messa, Andrea Nicola Paparella, Serena Perrone, Antonio Salomone
Summary: For the first time, Pd-catalyzed alkoxycarbonylation of aryl iodides has been investigated in phosphonium-based deep eutectic solvents under gas-free conditions using Mo(CO)(6) as the CO source. This method allows the efficient synthesis of ethylene glycol and glycerol esters with high yields (up to 99%), short reaction times, and mild reaction conditions, utilizing a remarkably low catalyst loading (0.5 mol%).
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Agricultural Engineering
Yu Yin, Chunhui Ma, Wei Li, Sha Luo, Yushan Liu, Xueyun Wu, Zhenwei Wu, Shouxin Liu
Summary: The study demonstrated the efficient conversion of glucose to 5-HMF in ionic liquids with MoCl3 as catalyst under microwave irradiation, with the ionic liquid [BMIM]Cl proving to be the best solvent. Microwave irradiation not only reduced the reaction time and improved the yield of 5-HMF compared to traditional oil-bath heating, but also accelerated the bond breaking processes in the reaction.
INDUSTRIAL CROPS AND PRODUCTS
(2021)
Review
Chemistry, Multidisciplinary
Thangavel Vijayakanth, David J. Liptrot, Ehud Gazit, Ramamoorthy Boomishankar, Chris R. Bowen
Summary: This article comprehensively reviews the application of piezo- and ferro-electric materials based on organic molecules and organic-inorganic hybrids in mechanical energy harvesting. The article describes the characterization of the piezo- and ferroelectric properties of these materials and highlights the advantages they have over traditional materials. It also discusses the potential of peptide-based and other biomolecular materials as alternative options. The article concludes with an analysis of the current limitations and future prospects in this field of research.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Laura E. English, Matthew D. Jones, David J. Liptrot
Summary: An N-heterocyclic phosphine (NHP) has been investigated as a catalyst for transesterification reactions of commercial polymer samples, displaying high degradation activity towards poly(lactic acid) with methanol. However, attempts to depolymerise other polymers were unsuccessful, and NHP was found to form a new active catalyst under transesterification conditions.
Article
Chemistry, Inorganic & Nuclear
Rex S. C. Charman, Mary F. Mahon, John P. Lowe, David J. Liptrot
Summary: Three ring-expanded N-heterocyclic carbene-supported copper(I) triphenylstannyls were synthesized and characterized. Reactions with various substrates yielded copper(I) benzamidinate, benzamide and benzothiamide via phenyl transfer from the triphenylstannyl anion. However, attempts to utilize this reactivity under a catalytic regime were hindered by rapid copper(I)-catalyzed dismutation reactions.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Laura E. English, Aleksandra Pajak, Claire L. McMullin, John P. Lowe, Mary F. Mahon, David J. Liptrot
Summary: Thermolysis of a 1,3-dioxa-2-phospholane supported by the terphenyl ligand Ar-iPr4 (Ar-iPr4=[C6H3-2,6-(C6H3-2,6-iPr(2))]) at 150 degrees C gives [(ArPO2)-P-iPr4](2), a dimeric compound with a 4-membered P-O-P-O ring. The structure of [(ArPO2)-P-iPr4](2) was confirmed by X-ray crystallography and NMR spectroscopy. It was found that the dimeric structure persisted in solution and this was supported by VT NMR spectroscopy and DOSY experiments. The addition of different ligands resulted in increased yield of the product at lower temperature.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Medicinal
Jack Ayre, Joanna M. Redmond, Giovanni Vitulli, Laura Tomlinson, Richard Weaver, Eleonora Comeo, Cynthia Bosquillon, Michael J. Stocks
Summary: A major limitation of pulmonary delivery is the rapid elimination of drugs from pulmonary tissue, resulting in suboptimal pharmacokinetic profiles. To overcome this, a series of dibasic dipeptides were attached to a pH-sensitive-linking group and evaluated. Compound 23, which showed good stability and high lung binding in vitro, was identified as the most promising candidate. Pharmacokinetic studies in rats demonstrated a total lung concentration of 23 at 31.2 μM at 24 hours post dosing. Furthermore, high levels of liberated drug 1 were still detected locally, indicating the potential of this prodrug approach in prolonging the apparent pharmacokinetic half-life of drugs in the lungs following pulmonary dosing.
JOURNAL OF MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Physical
Thomas M. Horsley Downie, Mary F. Mahon, John P. Lowe, Rowan M. Bailey, David J. Liptrot
Summary: The reaction of phosphorus(III) esters with pinacolborane using an NHC-copper(I) catalyst allows for the quick generation of various phosphines, which can be further used in the synthesis of different phosphorus-containing compounds. This telescoped approach provides access to a range of P-H bonded species with high conversions, enabling the synthesis of diverse phosphorus-based molecules without the need to handle toxic compounds.
Article
Chemistry, Multidisciplinary
Laura E. English, Thomas M. Horsley Downie, Catherine L. Lyall, Mary F. Mahon, Claire L. McMullin, Samuel E. Neale, Carla M. Saunders, David J. Liptrot
Summary: The (IPr)CuOtBu catalysed reduction of 11 aryl and alkyl isocyanates with pinacolborane resulted in the formation of boraformamides, pinBN(R)C(O)H, in most cases. Overreduction was observed only for electron poor aryl isocyanates (4-NC-C6H4NCO, 4-F3C-C6H4NCO, 3-O2N-C6H4NCO). Computational analysis revealed that the stability of [(IPr)CuH](2), proposed as the catalyst resting state, influences selectivity and offers a potential solution to prevent overreduction in future work. In the case of iPrNCO, the formation of [(IPr)CuH](2) prevents overreduction kinetically. However, for 4-NC-C6H4NCO, the barrier height for the first step of overreduction is much lower, resulting in unselective reduction.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Dawid J. J. Babula, Rex S. C. Charman, Thomas H. H. Jerome, Thomas M. Horsley M. Downie, Mary F. F. Mahon, David J. J. Liptrot
Summary: Sigma-bond metathesis reactions between [(6-Dipp)CuOtBu] and three diboranes resulted in the synthesis of three new copper(I) boryl complexes [(6-Dipp)CuBcat], [(6-Dipp)CuBneop], and [(6-Dipp)CuBhex]. While [(6-Dipp)CuBcat] and [(6-Dipp)CuBneop] formed rapidly, heating was required to obtain [(6-Dipp)CuBhex]. Crystallographic analysis revealed that all three complexes were monomers with distorted-linear structures at the copper atom. [(6-Dipp)CuBneop] exhibited comparable stability to [(IPr*)Cu-Bneop], remaining stable in solution for days without decomposition. [(6-Dipp)CuBhex] represents a rare example of a crystallographically characterized complex containing a boryl anion supported by a hexylene glycolato ligand.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Medicinal
Sebastian Dekkers, Birgit Caspar, Joelle Goulding, Nicholas D. Kindon, Laura E. Kilpatrick, Leigh A. Stoddart, Stephen J. Briddon, Barrie Kellam, Stephen J. Hill, Michael J. Stocks
Summary: In this study, fluorescent probes based on previously reported small-molecule antagonists were designed and synthesized using classic medicinal chemistry approaches to investigate the pharmacology and cellular distribution of the CXCR4 receptor. Three distinct chemical classes of fluorescent probes were developed and shown to specifically bind to the CXCR4 receptor in a fluorescence-based NanoBRET binding assay (pKD ranging 6.6-7.1). These probes were also used in competition binding experiments and confocal microscopy to further explore the pharmacology and cellular distribution of CXCR4.
JOURNAL OF MEDICINAL CHEMISTRY
(2023)
Article
Polymer Science
Fadi Soukarieh, Pratik Gurnani, Manuel Romero, Nigel Halliday, Michael Stocks, Cameron Alexander, Miguel Camara
Summary: Antimicrobial resistance is a global threat with a forecasted negative financial impact. Bacteria resistance is further enhanced by the ability to form biofilms, making most treatments ineffective. A study has developed polymers that improve the penetration of inhibitors to enhance biofilm antimicrobial activity.
Article
Chemistry, Multidisciplinary
Rex S. C. Charman, Josie A. Hobson, Ross A. Jackson, Mary F. Mahon, Samuel E. Neale, David J. Liptrot
Summary: In this study, two acyclic boryl complexes, (6-Dipp)CuB(OMe)2 and (6-Dipp)CuB(OMe)NMe2, were synthesized and their similar reactivities were demonstrated.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Pharmacology & Pharmacy
Yenju Chu, Abigail Wong, Haojie Chen, Liuhang Ji, Chaolong Qin, Wanshan Feng, Michael J. Stocks, Pavel Gershkovich
Summary: A military helicopter crash in Vietnam resulted in 13 deaths and 3 injuries. The cause of the accident is under investigation.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2023)
Article
Chemistry, Multidisciplinary
Sylwia Ostrowska, Pierre Arnaut, David J. Liptrot, Catherine S. J. Cazin, Steven P. Nolan
Summary: The synthesis, isolation, and full characterization of a new copper complex [Cu(IPr)(OC(H)(CF3)(2))] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) are reported. This copper(I) complex is a versatile synthon capable of activating various X-H bonds including C-H, N-H, and S-H bonds. [Cu(IPr)(OC(H)(CF3)(2))] was investigated as a pre-catalyst in several catalytic reactions.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Ross A. A. Jackson, Aidan J. R. Matthews, Petra Vasko, Mary F. F. Mahon, Jamie Hicks, David J. J. Liptrot
Summary: The potassium aluminyl complex K-2[Al{N(Dipp)SiMe3}(2)](2) was synthesized, representing the first example of an aluminyl anion supported by an acyclic ligand framework. Attempts to form the same structure with a larger ligand framework resulted in C-H cleavage. K-2[Al{N(Dipp)SiMe3}(2)](2) behaved as a nucleophilic source of aluminum, forming a monomeric, acyclic magnesium aluminyl complex when reacted with an electrophilic b-diketiminate supported magnesium(II) iodide.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Rex S. C. Charman, Thomas M. Horsley Downie, Thomas H. Jerome, Mary F. Mahon, David J. Liptrot
Summary: Frustrated Lewis pairs (FLPs) are widely applied catalysts that can react with various substrates, including water, hydrogen, and phenylacetylene. The reactivity of a specific FLP, (6-Dipp)CuC(=(NBu)-Bu-t)Bpin, was explored through synthetic studies and characterization techniques.
