Article
Chemistry, Multidisciplinary
Myojeong Kim, Euna You, Jieun Kim, Sungwoo Hong
Summary: An efficient method for functionalizing pyridines and quinolines through radical-mediated reactions has been developed, allowing for selective modification of heteroatom positions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Mathew M. Simpson, Ching Ching Lam, Jonathan M. Goodman, Shankar Balasubramanian
Summary: The epigenetic modification 5-methylcytosine is crucial for development, cell specific gene expression, and disease states. However, the selective chemical modification of 5-methylcytosine is currently challenging. In this study, we present a xanthone-photosensitized process that introduces a 4-pyridine modification at the methyl group of 5-methylcytosine. This reaction mechanism involves single electron oxidation and deprotonation to generate the methyl group radical, followed by cross coupling to install the 4-pyridine label.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Chang-Yin Tan, Myojeong Kim, Inyoung Park, Yuhyun Kim, Sungwoo Hong
Summary: A unified strategy for the deoxygenative or desulfurative pyridylation of various alcohols and thiols has been developed using a single-electron transfer (SET) process mediated by frustrated Lewis pairs (FLPs). The method involves the formation of FLPs between pyridinium salts and PtBu3, and the generation of alkyl radicals through the ionic coupling of phosphine radical cations with in situ generated xanthates. Visible-light irradiation enhances the reaction efficiency. This method offers a previously unrecognized opportunity for the selective heteroarylation of alcohols and thiols with diverse functional groups.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Tsuyoshi Taniguchi
Summary: In this Account, we describe our recent studies on the development of new synthetic methods using molecular oxygen (O-2) as an environmentally friendly oxidant. The electron acceptor property of O(2) can be utilized for activating simple organic molecules to generate reactive species, enabling advanced molecular transformations such as C-C and C-X bond formation and functionalization of inactivated C(sp(3))-H, while avoiding direct quenching by O-2.
Article
Chemistry, Multidisciplinary
Mohammed Sharique, Jadab Majhi, Roshan K. Dhungana, Lisa Marie Kammer, Matthias Krumb, Alexander Lipp, Eugenie Romero, Gary A. Molander
Summary: In this study, a simple, open-air, and efficient light-mediated Minisci C-H alkylation method is described, which is based on the formation of an electron donor-acceptor complex. Unlike previous protocols, this method does not require a photocatalyst, single electron transfer agent, or oxidant additive. The reaction can proceed under mildly acidic and open-air conditions, and it yields moderate to good amounts of Minisci alkylation products.
Article
Chemistry, Applied
Morgane de Robichon, David Branquet, Jacques Uziel, Nadege Lubin-Germain, Angelique Ferry
Summary: This study presents the synthesis of complex C-glycoconjugates using a key directed nickel-catalyzed C-H alkynylation step, allowing the insertion of diverse alkynyl moieties onto the pseudo-anomeric position of glycal substrates. These platforms were used in a click reaction with azides to form original C-glycoconjugates, leading to the synthesis of a C-glycosylated amino acid, a C-linked disaccharide, and a C-glycosylated biotin derivative. Preliminary conditions for removing the directing group are also proposed.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Applied
Jia-Bin Han, Htet Htet San, Ao Guo, Long Wang, Xiang-Ying Tang
Summary: An intriguing pyridine-boryl radical-mediated C-H alkynylation reaction of inactivated alkanes was described, featuring mild operation condition, wide substrate scope, and moderate to good yields. The presence of 4-cyanopyride N-oxide was crucial to the success of the reaction. Cyclohexane is more easily functionalized than toluene in this reaction, which can be rationalized by polarity-match principle.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Franco Della-Felice, Margherita Zanini, Xiaoming Jie, Eric Tan, Antonio M. Echavarren
Summary: The Rh-III-catalyzed allylic C-H alkynylation of non-activated terminal alkenes selectively leads to linear 1,4-enynes at room temperature. Additionally, the vinylic C-H alkynylation of alpha, beta- and beta, gamma- unsaturated amides gives conjugated Z-1,3-enynes and E-enediynes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Yanjun Wan, Emmanuel Ramirez, Ayzia Ford, Vanessa Bustamante, Gang Li
Summary: The study presents an iron-catalyzed method for accessing gamma-functionalized amides through C-H functionalization, involving the formation of an iron nitrenoid species and a specific mechanism. It demonstrates broad substrate compatibility and practicality, with the catalyst showing high turnovers on complex natural products.
Article
Chemistry, Organic
Di Fang, Yidan Zhang, Yiyun Chen
Summary: In this study, a novel photoredox catalysis method was reported for selective synthesis of delta- and epsilon-alkenols from aliphatic alcohols. N-Alkoxybenzimidoyl chlorides were used as alkoxyl radical precursors with tunable redox potentials, allowing for the construction of various alkenols through the inert C(sp(3))-H Heck-type reaction.
Article
Chemistry, Organic
Ramkrishna Laha, Twinkle I. Patel, Matthew J. Moschitto
Summary: A method for desulfinative alkylation of pyridine and quinoline N-methoxide salts is reported, which operates under both photocatalytic and electrostatic electron donor-acceptor-mediated pathways.
Article
Chemistry, Organic
Lei Liang, Ge Guo, Chen Li, Song-Lin Wang, Yue-Hui Wang, Hai-Ming Guo, Hong-Ying Niu
Summary: The study demonstrates Cu-catalyzed intermolecular alkynylation and allylation of unactivated C(sp(3))-H bonds with SOMO-philes via HAT, using N-fluoro-sulfonamide as a reagent, resulting in high yields, good regioselectivity, and functional-group compatibility. Late-stage functionalization of natural products and drug molecules is also shown in the research.
Article
Chemistry, Multidisciplinary
Sagar Arepally, Taehoon Kim, Gyeongho Kim, Haesik Yang, Jin Kyoon Park
Summary: This study presents the selective electrochemical synthesis of 1H-indazoles and their N-oxides, and the subsequent C-H functionalization. The outcomes of the electrochemical reactions were determined by the cathode material used. The broad scope of this electrochemical protocol allows for the synthesis of various bioactive molecules, making it attractive for pharmaceutical research and development. The synthetic utility of 1H-indazole N-oxides was demonstrated through the synthesis of pharmaceutical molecules and precursor for organic light-emitting diodes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Smruti Ranjan Mohanty, Namrata Prusty, Lokesh Gupta, Pragati Biswal, Ponneri Chandrababu Ravikumar
Summary: The Co(III)-catalyzed alkenylation of 2-pyridones using terminal alkyne as a reaction partner with high regioselectivity has been demonstrated for the first time. The reaction conditions are mild, compatible with a wide range of substrates, and show good functional group tolerance. High-resolution mass spectrometry detected the formation of five- and seven-membered cobaltacycle intermediates.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Kai Sun, Anzai Shi, Yan Liu, Xiaolan Chen, Panjie Xiang, Xiaotong Wang, Lingbo Qu, Bing Yu
Summary: A new method of photoactivation of electron donor-acceptor complexes between arylsulfonium salts and 1,4-diazabicyclo[2.2.2]octane with visible light or natural sunlight was discovered, enabling the generation of aryl radicals under mild conditions, offering a novel opportunity for two-step para-selective C-H functionalization of complex arenes.
Article
Chemistry, Organic
Xiaohan Chen, Lei Yan, Lu Zhang, Changyin Zhao, Guidong Feng, Lei Chen, Shutao Sun, Qingyun Liu, Lei Liu
TETRAHEDRON LETTERS
(2020)
Article
Chemistry, Physical
Ying Mao, Zehua Wang, Gang Wang, Ran Zhao, Linglong Kan, Xiaoguang Pan, Lei Liu
Article
Chemistry, Multidisciplinary
Pengbo Ye, Xuan Liu, Gang Wang, Lei Liu
Summary: An asymmetric alkylation method catalyzed by nickel(II) has been developed for preparing beta-alkoxyl carbonyl moieties with diverse alpha-substituents from acyclic oxocarbenium ions generated in situ from corresponding acetals with carboxylic acid derivatives. The method exhibits broad scope of acetals and carboxylic acid derivatives with excellent enantioselectivity and good functional group compatibility, and can be conducted in a gram-scale without obvious loss of efficiency.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Xiaohan Chen, Ran Zhao, Ziqiang Liu, Shutao Sun, Yingang Ma, Qingyun Liu, Xia Sun, Lei Liu
Summary: Chiral alpha-substituted 1,3-dihydroisobenzofurans are key scaffolds in various bioactive natural products and synthetic pharmaceuticals, with catalytic asymmetric approaches rarely developed. The adoption of redox deracemization technology effectively addresses this issue by achieving high efficiency and excellent ee values for a broad range of substrates.
CHINESE CHEMICAL LETTERS
(2021)
Article
Multidisciplinary Sciences
Gang Wang, Ran Lu, Chuangchuang He, Lei Liu
Summary: The study discusses the challenges and methods of catalytic kinetic resolution of amines, specifically focusing on the titanium-catalyzed asymmetric oxygenation with hydrogen peroxide. This approach allows for the efficient production of enantiopure hydroxylamines from secondary amines, demonstrating high chemoselectivity and enantio-discrimination. Late-stage asymmetric oxygenation of bioactive molecules is also explored in this research.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Xigong Liu, Changyin Zhao, Rongxiu Zhu, Lei Liu
Summary: The study presents a solution for constructing vicinal quaternary carbon stereocenters in acyclic systems, achieving excellent yields and selectivities through asymmetric cross-dehydrogenative coupling reactions. The generality of the approach was further demonstrated, and computational studies elucidated the origins of both diastereo- and enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Yasheng Zhu, Hongliang Wang, Gang Wang, Zehua Wang, Zhaopeng Liu, Lei Liu
Summary: The asymmetric 1,6-conjugate addition to delta-aryl-delta-cyano-disubstituted para-quinone methides has been achieved through bifunctional phosphonium-amide-promoted ion-pair catalysis, resulting in the construction of acyclic all-carbon quaternary stereocenters with high efficiency and excellent stereoselectivity. Both acyclic and cyclic 1,3-dicarbonyls participate in the reaction, providing a wide array of diarylmethanes with single acyclic quaternary carbon stereocenters or vicinal cyclic and acyclic quaternary carbon stereocenters. Computational studies have elucidated the origin of the enantioselectivity.
Article
Biochemistry & Molecular Biology
Jing Qin, Xia Sun, Yingang Ma, Yahong Cheng, Qiushuang Ma, Weiqiang Jing, Sifeng Qu, Lei Liu
Summary: The study constructed a library of 1,3,4,9-tetrahydropyrano[3,4-b]indoles using molecular hybridization strategy, with compound 23 showing potent activity against MDA-MB-231 cells by inhibiting the PI3K/AKT/mTOR pathway to induce apoptosis.
BIOORGANIC & MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Honghao Guan, Chen-Ho Tung, Lei Liu
Summary: Mimicking naturally occurring metalloenzymes for catalytic asymmetric oxidation reactions has been a long-standing goal in modern chemistry. In this study, a series of chiral diiron complexes mimicking methane monooxygenase (MMO) were designed and synthesized, exhibiting efficient catalytic reactivity in dehydrogenative kinetic resolution. The C9 complex was identified as the optimal catalyst with high chiral recognition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Pengbo Ye, Aili Feng, Lin Wang, Min Cao, Rongxiu Zhu, Lei Liu
Summary: Catalytic kinetic resolution of racemates is a powerful method for preparing enantiopure compounds, but it faces challenges when dealing with organic azides due to their small size and instability. Despite this, researchers have successfully achieved catalytic kinetic resolution of cyclic benzylic azides through site- and enantioselective C(sp3)-H oxidation.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Min Cao, Hongliang Wang, Yingang Ma, Chen-Ho Tung, Lei Liu
Summary: A manganese-catalyzed C-H azidation reaction with high site- and enantioselectivity has been developed. This practical method enables the azidation of tertiary benzylic C-H bonds with good functional group tolerance, leading to the efficient synthesis of diverse tertiary azide-containing indolines. The generality of the method was demonstrated by applying it to secondary azide-containing indolines. The method allows for the installation of various nitrogen-based functional groups and bioactive molecules with excellent site-, chemo-, and enantioselectivity at the C3 position of indoline frameworks.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Song Li, Haibei Li, Chen-Ho Tung, Lei Liu
Summary: This study reports a bio-inspired nonheme-iron-catalyzed method for the efficient and selective preparation of diversely functionalized organosilanols. The practical method allows for the synthesis of organosilanols with different substituent patterns and exhibits good functional group tolerance. The study also demonstrates the potential application of this method in the synthesis of functional molecules containing silanols.
Review
Chemistry, Multidisciplinary
Lei Liu
Summary: This article describes recent advances in the development and synthetic application of hydride-abstraction-initiated stereoselective intermolecular bond-forming processes. By utilizing the acetal pool strategy, the authors have achieved highly selective C-C and C-H bond formations, allowing the introduction of various functional groups with good substrate compatibility and synthetic utility.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Gang Wang, Tian Chen, Kuiyong Jia, Wencheng Ma, Chen-Ho Tung, Lei Liu
Summary: We report a new titanium-catalyzed asymmetric oxidation method for the preparation of diverse chiral hydroxylamines. This method exhibits excellent selectivity and functional group compatibility. This finding provides a new platform for chiral hydroxylamines as design elements for drug discovery.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Shutao Sun, Yingang Ma, Ziqiang Liu, Lei Liu
Summary: A novel manganese-catalyzed oxidative kinetic resolution method was reported, which effectively reacts asymmetric C(sp(3))-H oxidation to distinguish different types of cyclic benzylic ethers with wide application prospects and high enantiodiscrimination efficiency. This study further explores the direct late-stage oxidative kinetic resolution of bioactive molecules that are otherwise difficult to access.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
