Article
Chemistry, Multidisciplinary
T. Parker Maloney, Alexander F. Dohoda, Alec C. Zhu, Forrest E. Michael
Summary: In this study, we reported a convenient and transition metal-free intermolecular propargylic C-H amination of alkynes. The reaction showed high yields for terminal, silyl, and internal alkynes with a wide range of functional groups. The regioselectivity of amination was found to be influenced by substitution pattern and relatively remote heteroatomic substituents.
Article
Chemistry, Organic
Ziqin Zhang, Yifeng Chen, Linrong He, Lihua Xie, Zhitao Chen
Summary: We describe the construction of indole-fused seven-membered N- and O-heterocycles from indolyl alpha-diazo-carbonyls via photoredox-catalyzed intramolecular cyclization. The photoredox process allows for easy operation, mild conditions, and as low as 0.1 mol% catalyst loading, resulting in tricyclic heterocycles with yields of 24 to 67% and excellent regioselectivity. The practicality of this protocol is further demonstrated by gram-scale reactions carried out in both batch and continuous flow.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Ziqin Zhang, Yifeng Chen, Linrong He, Lihua Xie, Zhitao Chen
Summary: This paper describes the construction of indole-fused seven-membered N-and O-heterocycles from indolyl alpha-diazo-carbonyls via photoredox-catalyzed intramolecular cyclization. The photoredox process is characterized by its operational simplicity, mild conditions, and low catalyst loading. The tricyclic heterocycles are obtained with good regioselectivity in moderate to high yields. The practicality of this method is demonstrated by gram-scale reactions carried out in both batch and continuous flow.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Alvaro Velasco-Rubio, Jesus A. Varela, Carlos Saa
Summary: The Pd-catalyzed allylic C-H activation of simple olefins allows for the easy synthesis of seven-membered N,O-heterocycles such as 1,4-BZOs, 1,4-BZDs, and 1,4-oxazepanes in good to excellent yields. The straightforward derivatization of the olefinated 1,4-BZO demonstrates the synthetic utility of this methodology.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Dimitrios Andreou, Nsikak B. Essien, Cristina Pubill-Ulldemolins, Michael A. Terzidis, Athanasios N. Papadopoulos, George E. Kostakis, Ioannis N. Lykakis
Summary: A copper-mediated method was developed for the synthesis of seven-membered-ring fused pyrroles, allowing for the tolerance of various functional groups in the derivatives and exhibiting high antioxidant activity in selected examples. These rare 7-mrFPs can now be accessed on a millimolar scale.
Article
Chemistry, Multidisciplinary
Yinsong Zhao, Shaozhong Ge
Summary: The structural diversity of sp(3)-triorganometallic reagents enhances their potential in modular construction of molecular complexity in chemical synthesis. We report a selective triborylation reaction of unactivated alkenes to access synthetically versatile 1,1,3-triborylalkanes. This reaction provides a general platform for regioselective trifunctionalization of unactivated alkenes, and its utility is highlighted by the synthesis of various value-added chemicals from readily accessible unactivated alkenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Organic
Padinjare Veetil Saranya, Mohan Neetha, Sankaran Radhika, Gopinathan Anilkumar
Summary: This review summarizes the investigations on palladium-catalyzed synthesis of seven-membered heterocycles, highlighting the importance of heterocyclic compounds and the advantages of palladium in catalytic reactions.
JOURNAL OF HETEROCYCLIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Lei Bao, Bei-Bei Zhang, Zhi-Xiang Wang, Xiang-Yu Chen
Summary: We developed a simple and additive-free photocatalytic dehydration method using an organic photocatalyst 2,4,6-triphenylpyrylium salt for the efficient direct conversion of benzyl alcohols to the corresponding amides.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Shogo Nakamura, Soshi Nishino, Koji Hirano
Summary: A copper-catalyzed regioselective hydroamination method was developed to synthesize alpha-aminophosphonates from alpha,beta-unsaturated phosphonates, which are of interest in medicinal chemistry. The use of an umpolung, electrophilic amination strategy with a hydroxylamine derivative is key to achieving the desired regioselectivity, as compared to the conventional nucleophilic hydroamination conditions with the parent amine. The article also discusses the asymmetric synthesis using a chiral bisphosphine ligand and its application in a related silylamination reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Lu Lei, Pei-Sen Zou, Zhi-Xin Wang, Cui Liang, Cheng Hou, Dong-Liang Mo
Summary: A regioselective Heck reaction catalyzed by a P-containing palladacycle was described, which affords 2-aryl-2,5-dihydrofurans and 2-aryl-2,3-dihydrofurans in good yields from 2,3-dihydrofuran with diaryliodonium salts and aryl iodides, respectively. Mechanistic studies and DFT calculations revealed the chemoselectivity and regioselectivity-determining step of this reaction.
Article
Chemistry, Organic
Rodney A. Fernandes, Naveen Chandra, Ashvin J. Gangani, Gulenur N. Khatun
Summary: An efficient method for the synthesis of (E)-(3-alkoxybut-1-enyl)benzenes has been developed via Pd-catalyzed regioselective intermolecular hydroalkoxylation of 1-arylbutadienes. This method offers a simple operation, without the need for dry reaction conditions, and shows good tolerance to various substrates. The presence of chloromethyl methyl ether (MOMCl) as an additive is crucial to the success of the reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Chen-Yan Cai, Zheng-Jian Wu, Ji-Ying Liu, Ming Chen, Jinshuai Song, Hai-Chao Xu
Summary: Oxidative allylic C-H functionalization is a powerful tool in organic synthesis, minimizing the need for functional group activation and generating alkenyl-substituted products amenable to further modifications. The authors introduce an oxidant-free, electrocatalytic approach using tailored cobalt-salen complexes for intramolecular oxidative allylic C-H amination and alkylation, broadening the scope of such reactions.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Wanjun Chen, Yaping Cheng, Tao Zhang, Yu Mu, Wenqi Jia, Guodu Liu
Summary: A nickel-catalyzed stereoselective asymmetric intramolecular reductive coupling of N-1,6-alkynones was reported, achieving efficient synthesis of versatile functionalized chiral pyrrolidines with high yields, excellent stereoselectivity, and enantioselectivity. The developed reaction is applicable to a broad substrate scope and can be scaled up to gram scale without loss of enantioselectivity. The study also investigated ligand effects and reaction mechanism, suggesting wider applications in organic synthesis and chemical biology, and potential for further explorations in new research fields.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Chunyu Han, Yuanye Dang, Lin Mo, Ruofei Zhao, Zhengning Wang, Junfeng Zhao
Summary: A straightforward strategy for constructing seven-membered carbocycles through Lewis acid catalyzed intramolecular Michael addition of allenones is reported. It provides an atom-economic access to furan-fused bi- or tricyclic frameworks containing seven-membered carbocycles, which are commonly found in bioactive natural products. Several polycyclic frameworks containing seven-membered carbocycles with diverse functional groups were prepared in good to excellent yields. Furthermore, the strategy was exemplified by the construction of key skeletons of Caribenol A and Frondosin B.
Article
Chemistry, Organic
Xiaoying Li, Peihe Li, Zheng Wang, Hui Fu, Qipu Dai
Summary: Allylamine compounds were synthesized in one step by using aroyloxycarbamates as starting material, which was prepared in situ by inexpensive carboxylic acid and hydroxylamine. The reaction conditions are mild and the substrate is generally applicable, and it also achieved the synthesis of indole.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Lianqian Wu, Zhihan Zhang, Dunqi Wu, Fei Wang, Pinhong Chen, Zhenyang Lin, Guosheng Liu
Summary: An unprecedented highly enantioselective radical azidation of acrylamides catalyzed by 1 mol% of a copper catalyst is reported. The use of a specific ligand is crucial for generating a monomeric Cu-II azide species for this highly enantioselective transformation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Xiang Li, Pinhong Chen, Guosheng Liu
Summary: A palladium-catalyzed intermolecular alkynylcarbonylation of unactivated alkenes has been developed using ethynyl benziodoxolones as alkynylation reagents, providing efficient synthesis of beta-alkynylcarboxylic esters from simple alkenes. The reaction exhibits moderate to excellent regioselectivity and excellent functional group compatibility under mild reaction conditions.
CHEMICAL COMMUNICATIONS
(2022)
Review
Chemistry, Multidisciplinary
Zuxiao Zhang, Pinhong Chen, Guosheng Liu
Summary: Radical-involved transition metal catalysis enables new reactivities, and copper-catalyzed radical relay shows great potential in C(sp(3))-H functionalization. Significant progress has been made in asymmetric C-H functionalization through ligand design.
CHEMICAL SOCIETY REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Xiang Li, Jianbo Jin, Pinhong Chen, Guosheng Liu
Summary: Researchers have developed a palladium-catalyzed remote oxidative halogenation reaction for alkenes, leading to the efficient synthesis of primary alkyl halides. This study provides a cost-effective method to obtain valuable chemicals from readily available and inexpensive internal alkenes or mixtures of alkene isomers.
Article
Chemistry, Multidisciplinary
Xintuo Yang, Xiang Li, Pinhong Chen, Guosheng Liu
Summary: A novel Pd(II)-catalyzed enantioselective Markovnikov hydrooxygenation of unactivated terminal alkenes using a substituted pyridinyl oxazoline (Pyox) ligand has been developed. The (EtO)(2)MeSiH/BQ redox system is crucial for the highly selective and efficient hydrooxygenation, where alkylpalladium(II) species generated from enantioselective oxypalladation step is reduced by silane. This method provides an efficient access to optically pure alcohol esters from easily available alkenes with excellent enantioselectivities and features a broad substrate scope.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Dunqi Wu, Wenzheng Fan, Lianqian Wu, Pinhong Chen, Guosheng Liu
Summary: In this report, a copper-catalyzed asymmetric atom transfer radical addition (ATRA) reaction was studied, resulting in the successful synthesis of chiral chlorinated compounds using specific reagents and chiral ligands.
Article
Chemistry, Multidisciplinary
Pin Xu, Wenzheng Fan, Pinhong Chen, Guosheng Liu
Summary: The first enantioselective radical trifluoromethylation of benzylic C-H bonds has been achieved using a cooperative photoredox and copper catalysis system. This method provides straightforward access to structurally diverse benzylic trifluoromethylation products with excellent enantioselectivities under mild conditions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Wenzheng Fan, Xueyao Zhao, Yunshun Deng, Pinhong Chen, Fei Wang, Guosheng Liu
Summary: A highly efficient and sustainable method for enantioselective benzylic C-H cyanation has been reported by merging electrophoto-and copper catalysis. The novel catalytic system allows independent regulation of key steps to achieve high selectivity, suitable for enantioselective benzylic C-H cyanation of diverse alkylarenes and late-stage functionalization of bioactive molecules.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Xiang Li, Xintuo Yang, Pinhong Chen, Guosheng Liu
Summary: In this study, a remote hydro-oxygenation method of alkenes under palladium catalysis is reported, which efficiently yields linear alcohols from both terminal and internal alkenes. The use of a compatible SelectFluor/silane redox system plays a crucial role in achieving excellent chemo- and regioselectivities. The reaction exhibits a broad substrate scope and excellent functional group compatibility.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Liang Fu, Xin Chen, Wenzheng Fan, Pinhong Chen, Guosheng Liu
Summary: A novel asymmetric radical strategy for the straightforward synthesis of atropisomerically chiral vinyl arenes has been developed, proceeding through copper-catalyzed atroposelective cyanation/azidation of aryl-substituted vinyl radicals. The key to the success of the radical relay process is the atroposelective capture of highly reactive vinyl radicals with chiral L*Cu(II) cyanide or azide species. Furthermore, these axially chiral vinylarene products can be easily transformed into atropisomerically enriched amides and amines, enantiomerically enriched benzyl nitriles via an axis-to-center chirality transfer process, and an atropisomerically pure organocatalyst for the chemo-, diastereo-, and enantioselective (4 + 2) cyclization reaction.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Xiaonan Li, Tilong Yang, Jiayuan Li, Xiang Li, Pinhong Chen, Zhenyang Lin, Guosheng Liu
Summary: Palladium-catalyzed remote 1,n-dioxygenation (n = 4) of internal alkenes using engineered pyridine-oxazoline (Pyox) ligands is reported. The reactions exhibit high regio- and enantioselectivity, and have a broad substrate scope, providing optically pure 1,n-diol acetates as key synthons for bioactive molecules. Experimental and theoretical studies reveal that the regioselectivity is controlled by the reactivity disparity of two allylic C-H bonds, with the first palladium migration step being the regioselectivity-determining step facilitated by modified phenyl-substituted Pyox ligands.
Article
Chemistry, Organic
Changyu Shao, Chuanqi Hou, Pinhong Chen, Haihui Peng, Guosheng Liu
Summary: Here, the first enantioselective acetoxycarbonylation of internal (Z)-alkenes using a sterically hindered Quinox ligand is reported. The resulting acetoxyester products can be easily transformed into various biologically important molecules, with moderate to good yields and excellent enantioselectivities, as well as good functional group compatibility. The further transformation of these acetoxyesters into natural product analogues demonstrates the synthetic utility and application of this method.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yunshun Deng, Ronghua Lu, Pinhong Chen, Guosheng Liu
Summary: In this study, we achieved an enantioselective cyanation of propargylic C-H bonds through the combination of photoredox catalysis with a copper-catalyzed radical relay. The propargylic radical was generated by an intramolecular 1,5-HAT process. This reaction provides a straightforward approach to access optically pure propargyl nitrile compounds under mild conditions.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Zhongming Cheng, Tilong Yang, Can Li, Yunshun Deng, Fangjia Zhang, Pinhong Chen, Zhenyang Lin, Shengming Ma, Guosheng Liu
Summary: This study presents a copper-catalyzed radical relay strategy for the site-selective cyanation of sp(2) C-H bonds in allenes. The reactions show broad substrate scope and remarkable functional group compatibility under mild conditions. The site-selectivity is attributed to the unique pocket created by the Cu-bound nitrogen-centered radical and the crucial hydrogen bonding between the fluoride and the hydrogen atom. Late-stage functionalization of drug-like bioactive molecules containing an allene motif becomes feasible.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Pin Xu, Wenzheng Fan, Pinhong Chen, Guosheng Liu
Summary: The first enantioselective radical trifluoromethylation of benzylic C-H bonds has been established by a cooperative photoredox and copper catalysis system, providing straightforward access to structurally diverse benzylic trifluoromethylation products in good yields with excellent enantioselectivities under mild conditions. Merging the cooperative photoredox catalysis with copper catalysis is essential for the reaction, where the photoredox catalysis is used for the generation of benzylic radicals from alkyl arenes through a hydrogen atom transfer process and the copper catalysis is used for the enantioselective trifluoromethylation of the benzylic radicals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
