Article
Chemistry, Organic
Yanping Xia, Sen Wang, Rui Miao, Jianhua Liao, Lu Ouyang, Renshi Luo
Summary: Cationic iridium complexes were demonstrated to catalyze the transfer hydrogenation of oximes, providing access to N-alkoxy amines and hydroxylamines. The reaction rate was accelerated by trifluoroacetic acid. The practical application of this method was demonstrated by the synthesis of a fungicide in high yields, and the asymmetric synthesis of chiral N-alkoxy amines showed potential for further development.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Zheng Wang, Yahuan Liu, Mingyang Han, Ning Ma, Quanming Lyu, Qingbin Liu, Wen-Hua Sun
Summary: Molybdenum complexes with various structural features were developed and showed high activity in the transfer hydrogenation reaction. The products can be easily purified by removing the byproduct.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Applied
Rongrong Zhao, Qiao Wei, Yuxin Huang, Qin Qu, Qixing Liu, Haifeng Zhou
Summary: A one-pot synthesis of fluorinated chiral alcohols from alpha-bromoarylketones and fluoroalcohols is described. The fluorinated ketone intermediates were formed from alpha-bromoarylketones with fluoroalcohols as nucleophiles and solvents, which were reduced subsequentially by adding a chiral Ru catalyst and a mixture of formic acid and triethyl amines (FA: TEA=1.1:1) as hydrogen donor to give 27 examples of fluorinated chiral alcohols in 60-93% yields and 85-98% ee values. Notably, K3PO4 acts as a base in nucleophilic substitution and an additive in reductive step to enhance the reactivity and enantioselectivity, which is crucial for constructing compatible conditions for one-pot process. This one-pot process is also applicable to gram-scale synthesis.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
T. Roesler, J. Betting, S. Pueschel, A. J. Vorholt, W. Leitner
Summary: Efficient transformation protocols using ethylene glycol as a solvent, along with rhodium catalysts and amines as catalysts, can convert linear alpha olefins to alcohols. By incorporating amine functionality into the solvent, the reaction system can be simplified and achieve high catalytic activity. Amine functionalized PEG derivatives are used to immobilize the rhodium catalyst, and supercritical CO(2) is used as the extracting solvent for product alcohol recycling, without any loss in activity or selectivity.
Article
Chemistry, Organic
Victor Garcia-Vazquez, Pablo Martinez-Pardo, Alexandru Postole, A. Ken Inge, Belen Martin-Matute
Summary: This study developed a method for synthesizing chiral trifluoromethylated aliphatic amines, which involves organocatalytic isomerization and imine/enamine reduction to obtain compounds with two noncontiguous stereogenic centers in high yields and selectivities. The method is effective for primary amine substrates and provides a new pathway for synthesizing chiral trifluoromethylated scaffolds.
Article
Chemistry, Physical
Jianjun Wu, Zhenyu Chen, Jonathan H. Barnard, Ramachandran Gunasekar, Chunyang Pu, Xiaofeng Wu, Shiyu Zhang, Jiwu Ruan, Jianliang Xiao
Summary: A rhodium-catalysed reductive transamination reaction is reported for the synthesis of chiral piperidines and fluoropiperidines from simple pyridinium salts. The reaction demonstrates excellent diastereo- and enantio-selectivities and functional group tolerance, overcoming the limitations of asymmetric hydrogenation and traditional multistep synthesis.
Article
Chemistry, Organic
Ahreum Kim, Junsoo Moon, Chanhee Lee, Jayoung Song, Jongchan Kim, Yongseok Kwon
Summary: In this study, a highly enantioselective Pictet-Spengler reaction for the synthesis of axially chiral tetrahydroisoquinolines via dynamic kinetic resolution is reported. The cyclization catalyzed by chiral phosphoric acids leads to the formation of single regioisomeric isoquinolines with excellent enantioselectivities up to 99% ee around the C-C bond. The effectiveness of this protocol is demonstrated for a wide range of substrates, with enantiodivergence observed depending on the substituents on the catalysts.
Article
Chemistry, Multidisciplinary
Lei Yang, Wen-Qiang Xu, Tao Liu, Yichen Wu, Biqin Wang, Peng Wang
Summary: The synthesis of a Si-centered spirocyclic skeleton, SPOSiOL, and its derived chiral ligands were reported in this study, showcasing their potential in transition metal-catalyzed asymmetric reactions. This finding emphasizes the value of Si-centered spirocyclic scaffolds in asymmetric catalysis.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Jun Chen, Zhan Shi, Chunyu Li, Ping Lu
Summary: A sequential enantioselective reduction/C-H functionalization method was developed for installing contiguous stereogenic carbon centers of benzocyclobutenols and cyclobutanols. This strategy involves practical enantioselective reduction of a ketone and diastereospecific iridium-catalyzed C-H silylation, with further transformations explored, including controllable regioselective ring-opening reactions. Additionally, this strategy has been utilized for the synthesis of three natural products.
Review
Chemistry, Multidisciplinary
Patrick D. Parker, Xintong Hou, Vy M. Dong
Summary: Tandem catalysis allows for constructing complex structures quickly from simple building blocks to address diverse challenges. This article focuses on using tandem hydrogenation to prepare complex natural products and presents tandem catalysis involving transfer hydrogenation. Lastly, recent breakthroughs and opportunities for asymmetric hydrogenation are highlighted.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Kaili Zhang, Qixing Liu, Renke He, Danyi Chen, Zhangshuang Deng, Nianyu Huang, Haifeng Zhou
Summary: The asymmetric reduction of C = O bonds of 2-arylidene cycloalkanones using a chiral ruthenium complex as a catalyst and HCOOH/Et3N as a hydrogen source resulted in high yields and high enantiomeric excess. This method is not only suitable for small-scale synthesis, but also applicable for the gram-scale synthesis of pharmaceutically important compounds.
Article
Chemistry, Multidisciplinary
Tao Wang, Xiao-Yan Zhang, Yu-Cong Zheng, Yun-Peng Bai
Summary: A carbonyl reductase variant, SmCRM5, obtained from Serratia marcescens through structure-guided directed evolution, showed improved specific activity towards multiple substrates and high stereoselectivities in the asymmetric synthesis of gamma-/delta-lactones.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Liu-Yang Pu, Zhiyue Li, Limin Li, Yucui Ma, Shengquan Hu, Zhengzhi Wu
Summary: We report a concise asymmetric total synthesis of isopavine alkaloids, which possess a unique azabicyclo[3.2.2]nonane tetracyclic skeleton. The key steps involve iridium-catalyzed asymmetric hydrogenation of unsaturated carboxylic acids, Curtius rearrangement, and Eschweiler-Clarke methylation, achieving an enantioselective approach to isopavine alkaloids in 6-7 linear steps. Moreover, isopavine alkaloids, especially (-)-reframidine (3), are found to exhibit effective antiproliferative effects on various cancer cell lines for the first time.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Liu-Yang Pu, Zhiyue Li, Limin Li, Yucui Ma, Shengquan Hu, Zhengzhi Wu
Summary: In this study, we describe a concise and enantioselective total synthesis of isopavine alkaloids with a unique azabicyclo[3.2.2]nonane tetracyclic skeleton. Key steps include iridium-catalyzed asymmetric hydrogenation, Curtius rearrangement, and Eschweiler-Clarke methylation, enabling the synthesis of isopavine alkaloids in 6-7 linear steps. Additionally, we discovered that isopavine alkaloids, particularly (-)-reframidine (3), exhibit significant antiproliferative effects on various cancer cell lines for the first time.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Rurong Yu, Feiyue Hao, Xinyu Zhang, Zhongbing Fang, Zhengneng Jin, Guyue Liu, Guoliang Dai, Jiashou Wu
Summary: A method for selectively reducing 2-pyridyl ketones and related N-heteroaryl compounds using cobalt stearate as a catalyst and DMF as a hydride source has been developed. The chelation with cobalt activates the ketone substrate, making this method highly chemoselective. A possible reaction mechanism has been proposed based on control experiments.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Thomas H. Hall, Hannah Adams, Vijyesh K. Vyas, K. L. Michael Chu, Martin Wills
Summary: A detailed study was conducted on the asymmetric transfer hydrogenation (ATH) of a series of enones using Ru(II) catalysts. The ATH reaction can readily discriminate between double and triple bonds adjacent to ketones, reducing the double bond but leaving a triple bond intact in the major product.
Article
Chemistry, Physical
Abigail L. Whittock, Nazia Auckloo, Adam M. Cowden, Matthew A. P. Turner, Jack M. Woolley, Martin Wills, Christophe Corre, Vasilios G. Stavros
Summary: This study investigates the ultrafast dynamics of two photoprotective compounds and reveals their relaxation and cooling processes in solution after photoexcitation. The findings shed light on the essential components of microbial life and have implications for the development of molecular photon-to-heat converters for various applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Organic
Nastja Riemer, Martin Riemer, Mandy Krueger, Guy J. Clarkson, Michael Shipman, Bernd Schmidt
Summary: exo-Methylene-beta-lactams were synthesized in high yields as single isomers in a two-step reaction involving a Heck-type arylation with arene diazonium salts. The Pd-catalyzed coupling reaction showed high exo-regioselectivity and E-stereoselectivity in the beta-hydride elimination step. However, coupling products with aryl iodides, triflates, or bromides were obtained only in low yields due to extensive decomposition of the starting materials at elevated temperatures.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Jonathan Barrios-Rivera, Yingjian Xu, Guy J. Clarkson, Martin Wills
Summary: The application of enantiomerically-pure ruthenium(II) catalysts containing N - functionalised TsDPEN ligand to the asymmetric transfer hydrogenation of 15 examples of alpha-heterocyclic acetophenone derivatives is reported, with products of up to 99% ee formed. (C) 2021 Elsevier Ltd. All rights reserved.
Article
Chemistry, Multidisciplinary
Adedibu C. Tella, Adetola C. Oladipo, Victoria T. Olayemi, Allen Gordon, Adeniyi S. Ogunlaja, Lukman O. Alimi, Stephen P. Argent, Robert Mokaya, Guy J. Clarkson, Richard I. Walton
Summary: Two calcium coordination compounds were grown at room temperature and characterized. The structures of the compounds are stabilized by a network of hydrogen bonds. Compound 1 exhibits high excitation energies and chemical hardness, making it a better electron acceptor. Compound 2 is softer with better polarizability and reactivity.
STRUCTURAL CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Satarupa Das, Jinfang Zhang, Thomas W. Chamberlain, Guy J. Clarkson, Richard I. Walton
Summary: CO2 epoxidation to cyclic carbonates under mild, solvent-free conditions is a promising pathway for sustainable CO2 utilization. However, previous metal-organic frameworks (MOFs) used for this purpose are not suitable for commercial utilization due to the nonrenewable ligands used. This study presents new yttrium MOFs based on renewable 2,5-furandicarboxylate (FDC) ligands, which exhibit high catalytic activity and conversion efficiency for CO2 epoxidation reactions.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Guy J. Clarkson, Stefan Roesner
Summary: An efficient methodology for the synthesis of benzofuropyridines and dibenzofurans from fluoropyridines or fluoroarenes and 2-bromophenyl acetates is presented. The streamlined one-pot procedure involves four-step directed ortho-lithiation, zincation, Negishi cross-coupling, and intramolecular nucleophilic aromatic substitution, enabling the easy assembly of a diverse set of fused benzofuro heterocycles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Jiangping Liu, Andrew W. Prentice, Guy J. Clarkson, Jack M. Woolley, Vasilios G. Stavros, Martin J. Paterson, Peter J. Sadler
Summary: This study reports a Ru(II) polypyridyl prodrug, RuAzNM, functionalized with azo and nitrogen mustard, which exhibits multimodal theranostic properties towards hypoxic cancer cells. Reduction of the azo group in hypoxic cell microenvironments leads to the generation of reactive oxygen species and mtDNA crosslinking, while the resulting phosphorescent RuNH2 serves as a diagnostic signal and activates phototherapy. This unique strategy allows controlled multimodal theranostics to be realized in hypoxic cells, making RuAzNM a highly selective and effective cancer-cell-selective theranostic agent.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Noha Khamis, Guy J. Clarkson, Martin Wills
Summary: The synthesis of a variety of N-(heterocyclesulfonyl)-functionalized Noyori-Ikariya catalysts was described in this study. These complexes were prepared from C2-symmetric 1,2-diphenylethylene-1,2-diamine (DPEN) and characterized using multiple methods including X-ray crystallography. The complexes exhibited catalytic activity in the asymmetric transfer hydrogenation (ATH) of various acetophenone derivatives, yielding products with high enantioselectivity in most cases, especially for ortho-substituted acetophenones.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Organic
Ye Zheng, Martin Wills
Summary: In this study, the reduction of Bpin-containing ketones by asymmetric transfer hydrogenation (ATH) was investigated. It was found that the reaction products exhibited high ee when the Bpin group was in the para- or meta-position.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Feng Chen, Isolda Romero-Canelon, Abraha Habtemariam, Ji-Inn Song, Samya Banerjee, Guy J. Clarkson, Lijiang Song, Ivan Prokes, Peter J. Sadler
Summary: We synthesized a series of novel substituted sulfonyl ethylenediamine (en) Ru-II arene complexes, which showed antiproliferative activity against cancer cells and exhibited catalytic activity in transfer hydrogenation reactions and reactions with thiols.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Russell J. Needham, Ivan Prokes, Abraha Habtemariam, Isolda Romero-Canelon, Guy J. Clarkson, Peter J. Sadler
Summary: In this study, the synthesis and characterization of an organo-osmium anticancer complex, along with its potent activity against human ovarian cancer cells, were reported. The X-ray crystal structure confirmed the unique configuration of the complex, and analysis of the isotopically-enriched compound provided insights into its chemical shifts and bonding interactions.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Inorganic & Nuclear
Evyenia Shaili, Maria J. Romero, Luca Salassa, Julie A. Woods, Jennifer S. Butler, Isolda Romero-Canelon, Guy Clarkson, Abraha Habtemariam, Peter J. Sadler, Nicola J. Farrer
Summary: The synthesis and characterization of four platinum complexes were conducted and analyzed using various methods. Complexes 1-3 demonstrated phototoxicity under green light irradiation, with complexes 1 and 2 exhibiting higher photocytotoxicity and activity against cisplatin-resistant cell lines.
DALTON TRANSACTIONS
(2021)
