Article
Chemistry, Multidisciplinary
Ricardo Rodriguez, Marina Sicignano, Jose Aleman
Summary: In this study, a convenient strategy using gem-difluorinated sulfinates as upgrading-masks is reported, which allows the decomposition of precursors into corresponding alkyl radicals. The stereocontrolled light-driven insertion of gem-difluoro derivatives into unsaturated aldehydes is achieved.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Mingxin Liu, Nguyen Le, Christopher Uyeda
Summary: Nickel catalysts promote nucleophilic cyclopropanation reactions using CH2Cl2 as a methylene source and Mn as a stoichiometric reductant. The substrate scope includes a broad range of alkenes bearing electron-withdrawing substituents, and enantioselective cyclopropanations have been developed using chiral PyBox ligands. Mechanistic studies suggest the intermediacy of a (PyBox)Ni=CH2 species and DFT models provide a rationale for the nucleophilic character of the nickel carbene and the sense of enantioinduction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Multidisciplinary
Johannes Grosskopf, Thorsten Bach
Summary: Upon irradiation with a suitable chiral catalyst, racemic compounds can be converted into enantiopure compounds through a process called photochemical deracemization. This review comprehensively covers the research and current developments in this field, discussing the reactions and mechanistic details underlying the presented reaction. Photochemical deracemization offers a unique opportunity to directly obtain enantiopure compounds from racemates, and short-lived intermediates play a key role in determining the enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
David Weinzierl, Magdalena Piringer, Paul Zebrowski, Lotte Stockhammer, Mario Waser
Summary: Enantioselective synthesis of alpha-chlorinated carboxylic acid esters was achieved with er up to 99:1 and yields up to 82% via a one-pot multistep protocol starting from alpha-diazoketones. This process involves a photochemical Wolff rearrangement, enantioselective alpha-chlorination using a chiral Lewis base catalyst, and a final nucleophilic displacement of the bound catalyst. The resulting products were successfully used for stereospecific nucleophilic displacement reactions with N- and S-nucleophiles.
Article
Chemistry, Multidisciplinary
Soumyadeep Chakrabortty, Shasha Zheng, Fabian Kallmeier, Eszter Barath, Sergey Tin, Johannes G. de Vries
Summary: A readily available chiral Ru/bisphosphine catalyst was used to achieve the direct asymmetric reductive amination of bio-based levulinic acid (LA) to produce enantioenriched 5-methylpyrrolidinone with excellent enantioselectivity (up to 96% ee) and high isolated yield (up to 89%). Methyl levulinate (ML), a byproduct from the industrial production of 2,5-furandicarboxylic acid (FDCA), can be used as a substitute for LA with similar reactivity and selectivity. Mass spectrometry and isotope labelling studies suggest that the chiral lactam is formed through imine-enamine tautomerization/cyclization followed by asymmetric hydrogenation of the cyclic enamide.
Article
Chemistry, Multidisciplinary
Fuad O. Usman, Achyut R. Gogoi, Jason C. Mixdorf, Osvaldo Gutierrez, Hien M. Nguyen
Summary: In this study, an enantioselective synthesis of 1,2-disubstituted allylic fluorides using a chiral diene-ligated rhodium catalyst was reported. Kinetic studies and calculations were conducted to investigate the molecular structure and reaction kinetics of the formation process of 1,2-disubstituted allylic fluorides. The reaction selectivity and yield of the construction process of 1,2-disubstituted allylic fluorides were also identified.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Daniel Lowicki, Justyna Watral, Maciej Jelecki, Wiktor Bohusz, Marcin Kwit
Summary: An efficient enantioselective protonation of 2-methyl-1-tetralone lithium enolate catalyzed by salan-type diamines is reported in this study. A broad series of salan-type catalysts were synthesized and tested in the reaction, with a chiral amine organocatalyst showing better results than a stoichiometric protonating agent for the first time. The use of only 10 mol% of salan allows for high yield and enantiomeric excess up to 75% in obtaining the title ketone.
Review
Chemistry, Multidisciplinary
Jia-Jun Jiang, Man-Kin Wong
Summary: This review summarizes the rapid development of asymmetric gold catalysis in the past ten years, focusing on newly developed gold-catalyzed enantioselective organic transformations and recent progress in ligand design since 2016, organized according to different types of chiral ligands for asymmetric gold(I) and gold(III) catalysis.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Junjie Meng, Hui He, Qianru Liu, Hanhong Xu, Huicai Huang, Shao-Fei Ni, Zhaodong Li
Summary: A PdII-catalyzed domino enantioselective desymmetrizative coupling of 7-azabenzonorbornadienes with alkynylanilines is described, which generates valuable functionalized compounds with excellent enantio- and diastereo-selectivity. The method allows the construction of multiple covalent bonds and stereocenters in an efficient and atom-economical manner.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Zhikun Zhang, Xile Hu
Summary: A catalytic deracemization method for secondary benzylic alcohols has been developed, utilizing sequential photochemical dehydrogenation followed by enantioselective thermal hydrogenation. The combination of a heterogeneous dehydrogenation photocatalyst and a chiral molecular hydrogenation catalyst enables the conversion of racemic aryl alkyl alcohols into their enantiomerically enriched forms.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Liyin Jiang, Pau Sarro, Wei Jie Teo, Jordi Llop, Marcos G. Suero
Summary: The new method described in this study involves the construction of fluorinated tertiary stereocenters through the cleavage of alkene C(sp(2))-C(sp(2)) bonds. This Rh-catalyzed carbyne transfer allows for a branched-selective fluorination of tertiary allyl cations, with a wide scope that includes natural products, drug molecule derivatives, and radiofluorination.
Article
Chemistry, Organic
Riccardo Pedrazzani, Juzeng An, Magda Monari, Marco Bandini
Summary: New chiral BINOL-based phosphate counterions have been synthesized and utilized in the gold-catalyzed enantioselective dearomatization reaction, leading to a range of densely functionalized C1-allylated naphthalenones with high levels of chemo-, regio-, and stereoselectivity (up to 95% ee).
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Ningbo Li, Yuxin Wang, Shuo Gu, Chuqian Hu, Qian Yang, Zhaohui Jin, Wen-Tao Ouyang, Jie Qiao, Wei-Min He
Summary: A concise and efficient ring-opening difluorination strategy has been developed for the synthesis of highly functionalized hydroxy-containing α,α-difluoro-β-ketoamides. This transition-metal-free synthetic procedure showed good functional group compatibility and attractive practical potential for large-scale synthesis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Xingchen Dong, Shuting Lv, Qianqian Qi, Youkun Gu, Peizhe Wu, Wenyue Zhang, Zhuolin Zhang, Libing Yang, Jiaqi Li, Yashao Chen, Changhao Wang
Summary: The structures of DNA can be used as chiral scaffolds for DNA-based asymmetric catalysis. However, the complex structures of DNA hybrid catalysts often hinder the understanding of their structure-activity relationship. Nucleotide-based catalysts provide a promising approach to obtain fine structural information and understand catalytic mechanisms. In this study, a cyclic dinucleotide (c-di-AMP) and 1,10-phenanthroline copper(II) nitrate (Cu(phen)(NO3)2) were assembled to form a c-di-AMP-based catalyst (c-di-AMP/Cu(phen)(NO3)2), which exhibited high yields and enantioselectivity in enantioselective fluorination reactions in water.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Applied
Gabriele Lupidi, Alessandro Palmieri, Marino Petrini
Summary: N-Activated ketimines are characterized by electron-withdrawing groups linked to the nitrogen atom, enhancing the electrophilic character and allowing addition reactions with weak nucleophiles. The presence of oxygen atoms in these groups is crucial for asymmetric catalytic reactions. This review summarizes the literature on the synthesis of optically active alpha-substituted amino derivatives using open-chain N-activated ketimines.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Jian Cao, Ling Chen, Feng-Na Sun, Yu-Li Sun, Ke-Zhi Jiang, Ke-Fang Yang, Zheng Xu, Li-Wen Xu
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2019)
Article
Chemistry, Multidisciplinary
Yu-Li Sun, Xing-Ben Wang, Feng-Na Sun, Qian-Qian Chen, Jian Cao, Zheng Xu, Li-Wen Xu
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2019)
Article
Chemistry, Organic
Shuai Shuai Huang, Zhan Jiang Zheng, Yu Ming Cui, Zheng Xu, Ke Fang Yang, Li Wen Xu
SYNTHESIS-STUTTGART
(2019)
Article
Chemistry, Physical
Qing Wang, Fei Ye, Jian Cao, Zheng Xu, Zhan-Jiang Zheng, Li-Wen Xu
CATALYSIS COMMUNICATIONS
(2020)
Article
Chemistry, Multidisciplinary
Jun-Han Ma, Li Li, Yu-Li Sun, Zheng Xu, Xing-Feng Bai, Ke-Fang Yang, Jian Cao, Yu-Ming Cui, Guan-Wu Yin, Li-Wen Xu
SCIENCE CHINA-CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Zhao Li, Xu Wang, Yu-Ming Cui, Jun-Han Ma, Li-Lei Fang, Lu-Lu Han, Qin Yang, Zheng Xu, Li-Wen Xu
Summary: The study successfully combined palladium-catalyzed DKR with C-H functionalization to synthesize non-biaryl-atropisomer-type (NBA) axially chiral organosilanes, providing a new approach for the synthesis of multifunctional axially chiral organosilicon compounds.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Xiao-Bing Chen, Li Li, Wan-Chun Yang, Kun-Long Song, Bin Wu, Wan-Er Gan, Jian Cao, Li-Wen Xu
Summary: In this study, a novel palladium-catalyzed C-C bond activation of methylenecyclobutanes followed by Suzuki cross-coupling reaction was reported, leading to the formation of multisubstituted indanes. The tandem reaction process involves intramolecular carbopalladation of double bond, beta-carbon elimination, and intermolecular trapping of the transient sigma-alkylpalladium complex with boronic acids. A new TADDOL-derived phosphoramidite ligand containing fluorine and silicon-based bulky groups was found to be efficient for C-C bond activation of methylenecyclobutanes.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Organic
Wan-Chun Yang, Xiao-Bing Chen, Kun-Long Song, Bin Wu, Wan-Er Gan, Zhan-Jiang Zheng, Jian Cao, Li-Wen Xu
Summary: This study demonstrated a palladium-catalyzed asymmetric tandem C-C bond activation/Cacchi reaction between cyclobutanones and o-ethynylanilines, leading to the synthesis of one-carbon-tethered chiral indanone-substituted indoles with multiple new bonds and stereocenters.
Article
Chemistry, Multidisciplinary
Jia-Le Xie, Zheng Xu, Han-Qi Zhou, Yi-Xue Nie, Jian Cao, Guan-Wu Yin, Jean-Philippe Bouillon, Li-Wen Xu
Summary: The study presents a highly enantioselective hydrosilylation of ynones using a palladium catalyst with a chiral ligand, leading to the formation of a series of silicon-stereogenic silylenones with high yield and enantioselectivity. The reaction mechanism and origin of high degree of stereoselectivity were elucidated through density functional theory calculations, highlighting the importance of aromatic interactions in the reaction.
SCIENCE CHINA-CHEMISTRY
(2021)
Article
Chemistry, Organic
Fei Ye, Li-Wen Xu
Summary: Silicon and its related organosilicon chemistry have become integral parts of synthetic chemistry due to their ability to participate in various organic transformations. The advances in catalytic hydrosilylation and synthesis of silicon-stereogenic silanes demonstrate the significance and potential of organosilicon chemistry in academic research and industrial applications.
Article
Chemistry, Multidisciplinary
Hui-Lin Li, Wei-Sheng Huang, Fang-Ying Ling, Li Li, Jun-Hao Yan, Hao Xu, Li-Wen Xu
Summary: Organosilicon compounds are important reagents and intermediates in the construction of new materials and complex products. In this study, a highly diastereoselective rhodium-catalyzed cycloisomerization reaction was demonstrated using (EtO)3SiH to accelerate the cyclization reaction and yield spiro-fused succinimide and pyrazolone derivatives as a single diastereoisomer. The proposed mechanism involves an active Rh-H species from the hydrosilane as the H-donor in the spiro-type cycloisomerization reaction.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Organic
Kun-Long Song, Bin Wu, Wan-Er Gan, Wan-Chun Yang, Xiao-Bing Chen, Jian Cao, Li-Wen Xu
Summary: The palladium-catalyzed carbonylative C-C bond activation reaction described in this study involves C-C bond cleavage, ring-opening, and amino- or alkoxycarbonylation reactions on cyclobutanones. Two C-C bonds and one C-O or C-N bond are formed under gas-free conditions using CO surrogates, yielding a variety of indanones with ester or amide groups.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Qiu-Qi Mu, Yi-Xue Nie, Hang Li, Xing-Feng Bai, Xue-Wei Liu, Zheng Xu, Li-Wen Xu
Summary: This study achieved highly enantioselective kinetic resolution of sterically hindered benzylamines for the first time through transition-metal-catalyzed oxidative carbonylation, providing a new approach to chiral isoindolinones (er up to 97:3). The origin of chemoselectivity and stereoselectivity was confirmed by density functional theory (DFT) calculations.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Li Li, Yun-Long Wei, Li-Wen Xu
Article
Chemistry, Multidisciplinary
Qiao-Ying Sun, Zhao Li, Zheng Xu, Zhan-Jiang Zheng, Jian Cao, Ke-Fang Yang, Yu-Ming Cui, Li-Wen Xu
CHEMICAL COMMUNICATIONS
(2019)