Article
Chemistry, Organic
Yu-Yong Luan, Jin-Ye Li, Xue-Ya Gou, Wei-Yu Shi, Tian Ding, Zhe Zhang, Xi Chen, Xue-Yuan Liu, Yong-Min Liang
Summary: Herein, a stereoselective synthesis of multisubstituted alkenes was reported via ruthenium-catalyzed remote migration arylation of nonactivated olefins. This strategy has wide substrate suitability and excellent functional group tolerance. Additionally, the indispensable role of two types of ruthenium was demonstrated through mechanism experiments.
Article
Chemistry, Multidisciplinary
Xinran Chen, Hasret Can Guelen, Jun Wu, Zi-Jing Zhang, Xin Hong, Lutz Ackermann
Summary: Ruthenium-catalyzed sigma-bond activation-assisted meta-C-H functionalization has gained significance in the formation of distal C-C bonds. However, the lack of mechanistic studies has hindered a complete understanding of the site-selectivity and reaction pattern. In this study, computational investigations were conducted on ruthenium-catalyzed C-H functionalization using alkyl bromides and aryl bromides. Monocyclometalated ruthenium(II) complexes were identified as the active species, with inner-sphere single electron transfer (ISET) facilitating the activation of organic bromides. The competition between reductive elimination and radical coupling determines the site-selectivity, which was further predicted using a multilinear regression model validated by experiments.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Yan-Ying Zhu, Hui-Bei Xu, Jing Zhang, Yi Luo, Lin Dong
Summary: Fluorinated compounds are widely used in agrochemicals, pharmaceuticals, and biochemical sciences. In this study, an efficient Ru(II)-catalyzed site-selective C-H functionalization/difluoromethylated reaction was developed to synthesize 3-difluoromethylated and remote meta-difluoromethylated 7-azaindole derivatives separately.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yuncong Luo, Shengjie Jiang, Xin Xu
Summary: This work reports a novel site-selective C-H borylation reaction of pyridines at the ortho-position using a yttrocene catalyst, enabling the introduction of boronate groups. The resulting boronates exhibit a broad substrate scope and high atom efficiency, and can undergo various transformations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Xiaolin Shi, Zemin Wang, Yuxiu Li, Xiaowei Li, Xiangqian Li, Dayong Shi
Summary: The study reports a challenging palladium-catalyzed remote C4-H phosphonylation of indoles using a radical approach. The method not only provides a new synthetic pathway, but also unexpectedly obtained C6-phosphonylated indoles, suggesting a potential strategy for future cross-coupling reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Jingjie Yang, Zhuofan Gui, Yuli He, Shaolin Zhu
Summary: An attractive approach for selective functionalization of remote C-H bonds is the metal/hydride shift/cross-coupling reaction sequence. In this study, an unprecedented aryl-to-vinyl 1,4-nickel/hydride shift reaction is reported, which selectively traps migratory alkenylnickel species generated in situ by various coupling partners to access trisubstituted alkenes with excellent regio- and stereoselectivity. Unlike previously reported ipso-aryl coupling reactions, this strategy provides remote alkenyl C-H functionalized products with high yield and excellent chemo-, regio-, and E/Z-selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Qi-Jun Yao, Fan-Rui Huang, Jia-Hao Chen, Ming-Yu Zhong, Bing-feng Shi
Summary: In recent years, the merging of electrosynthesis with 3d metal catalyzed C-H activation has been developed as an effective technique in organic synthesis. However, an enantioselective version of this technique is still challenging. This study presents the first electrooxidative cobalt-catalyzed enantioselective C-H/N-H annulation with olefins at room temperature. The mechanism of the reaction was elucidated through cyclovoltametric studies and the preparation of cobaltacycle intermediates.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Arup Mondal, Manuel van Gemmeren
Summary: Alkynes are important motifs in organic synthesis due to their presence in natural products and bioactive molecules. The method of inserting alkynes into (hetero)arenes relies heavily on the regioselectivity of the halogenation step, and can achieve selective alkynylation of thiophenes. The developed palladium-catalyzed C-H activation/alkynylation of thiophenes allows for regiodivergent reactions and late-stage modifications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Organic
Priyank Purohit
Summary: This article presents the challenge of regiospecific and atom economic C-C bond formation, which has been addressed by directing group and organometal-based C-H activation strategy. Organometals like Ru, Pd, Pt, Ni have been discovered as effective catalysts for C-H activation without the need for pre-activation of the inert C-H bond. This study focuses on cationic ruthenium and its unique reactivity with inert substrates.
CURRENT ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Anais Loison, Gilles Hanquet, Fabien Toulgoat, Thierry Billard, Armen Panossian, Frederic R. Leroux
Summary: In this study, we report the in situ generation of a novel intermediate, difluoromethoxylated ketenimines, obtained from the corresponding oxime through a Beckmann rearrangement. The reactivity potential of this intermediate is demonstrated as it easily undergoes addition reactions with various nucleophiles. The broad applicability of this transformation leads to a chemical library of original molecules bearing -OCHF2, an Emergent Fluorinated Group (EFG).
Article
Chemistry, Multidisciplinary
Sun Dongbang, Jonathan A. Ellman
Summary: In this study, a three-component strategy was disclosed to access quaternary centers bearing nitriles via cobalt-catalyzed C-H bond activation and sequential addition. Various functionalized nitriles were successfully synthesized by using different types of dienes. The synthetic utility of the nitrile products was demonstrated by various transformations, showcasing the potential for further organic synthesis applications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Khalid Boujdi, Nabil El Brahmi, Sylvain Collet, Didier Dubreuil, Monique Mathe-Allainmat, Mohamed Akssira, Gerald Guillaumet, Jacques Lebreton, Said El Kazzouli
Summary: A new solvent/ligand-controlled switchable C-H arylation of 1-methyl-4-nitro-1H-indazole catalyzed by Pd(OAc)(2) was achieved. Activation at the C7 position was promoted by a bidentate ligand in DMA, while arylation at the C3 position was directed by a phosphine ligand in H2O. The C3 and C7 arylation products were obtained in moderate to good yields and with high regioselectivity.
SYNTHESIS-STUTTGART
(2022)
Article
Biochemistry & Molecular Biology
Ming Zeng, Jiaqi Chen, Fengye Li, Haojie Li, Lan Zhao, Dengzhao Jiang, Jun Dai, Wenbo Liu
Summary: 1,3,5-triazines, especially indole functionalized triazine derivatives, have shown excellent activities in anti-tumor, antibacterial, and anti-inflammatory fields. Traditional methods for synthesizing N-(2-triazine) indoles have limitations due to unstable materials and complex operations. In this study, an efficient ruthenium-catalyzed oxidative synthesis of N-(2-triazine) indoles by C-H activation was developed, resulting in moderate to good yields. The reaction proceeded through a proposed six-membered ruthenacycle intermediate, indicating the chelation assistance of the triazine ring in the formation of N-(2-triazine) indoles.
Article
Chemistry, Multidisciplinary
Yulei Wang, Hendrik Simon, Xinran Chen, Zhipeng Lin, Shan Chen, Lutz Ackermann
Summary: While electrochemical ortho-selective C-H activations are well established, the development of distal C-H activations is still limited. In this study, we report the electrochemical meta-C-H functionalization, achieving remote C-H bromination in an undivided cell under ligand- and electrolyte-free conditions. Notably, pyrazolylarenes were selectively brominated at the benzenoid moiety rather than the electron-rich pyrazole ring for the first time. Mechanistic studies suggested the formation of a ruthenacycle followed by a ligand-to-ligand hydrogen transfer (LLHT) process.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Lin Lin, Xue-jun Zhang, Xinyu Xu, Yue Zhao, Zhuangzhi Shi
Summary: This study reports a modular assembly method for diverse phosphine-amide ligands, using ruthenium-catalyzed C-H activation of phosphines with isocyanate directed by phosphorus(III) atoms. The method enables efficient and selective synthesis of various phosphine-amide ligands, some of which show excellent efficiency for asymmetric catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Dan Liu, Kai Yang, Di Fang, Shi-Jun Li, Yu Lan, Yiyun Chen
Summary: This study reports the first method for generating formyl radicals from alpha-chloro N-methoxyphthalimides, which selectively synthesize aldehydes under mild photoredox conditions. The method exhibits excellent chemoselectivity and regioselectivity for installing aldehydes on various organic compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Tao Zhang, Kangbao Zhong, Zhi-Keng Lin, Linbin Niu, Zi-Qi Li, Ruopeng Bai, Keary M. Engle, Yu Lan
Summary: In this study, computational evidence is presented to support the role of Zn coordination in accelerating reductive elimination from Ni(II) centers in Ni-catalyzed cross-couplings. The Zn-assisted pathway was found to have lower energy compared with direct reductive elimination from a Sigma-coordinated Ni(II) intermediate. Theoretical calculations reveal a significant Z-type Ni-Zn interaction that enhances reductive elimination.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Xinghua Wang, Ya-Nan Wang, Zhipeng Pei, Shi-Jun Li, Donghui Wei, Yu Lan
Summary: Great success has been achieved in the precise construction of C-C bonds under N-heterocyclic carbene (NHC)/ Bronsted acid (BA) cooperative catalysis. However, the mechanism behind the acceleration of conversions of alpha,beta-unsaturated carbonyls by NHC and BA co-catalyst remains unclear. In this study, several representative NHC/BA cooperative catalysis models were systematically studied to enhance chemists' understanding of these reactions. The identification and confirmation of favorable models for the NHC/BA cooperatively catalyzed reactions of alpha,beta-unsaturated carbonyls were done using proposed combination rules of hydrogen bond donor/acceptor-electrophile/nucleophile and reactivity index (Rk). This work is significant for comprehending the cooperative catalytic mechanism and provides valuable insights for designing efficient cooperative catalytic reactions with specific selectivity.
Article
Chemistry, Multidisciplinary
Haizhen Wang, Di Liu, Haifeng Chen, Yuqing Jiao, Haixin Zhao, Zongcheng Li, Siyuan Hou, Yanli Ni, Rong Zhang, Jinyong Wang, Jie Zhou, Bing Liu, Yu Lan
Summary: During the development of mid-gestational mouse embryos, specialized endothelial cells called hemogenic endothelial cells (HECs) differentiate into hematopoietic stem and progenitor cells (HSPCs) through a process called endothelial-to-hematopoietic transition (EHT). This study reveals that the gene Nupr1, previously identified as a signature gene of HECs, negatively regulates the EHT process. Deletion of Nupr1 in endothelial cells leads to increased HSPC generation in the aorta-gonad-mesonephros region. The study also finds that the proinflammatory cytokine TNF-alpha is upregulated in Nupr1-deficient HECs, and neutralizing TNF-alpha partially reduces excessive HSPC generation. These findings suggest that Nupr1 could be a potential target for future research on hematopoietic stem cell regeneration.
Article
Multidisciplinary Sciences
Jun Wu, Shi-Jun Li, Long Jiang, Xiao-Chi Ma, Yu Lan, Li Shen
Summary: This study presents a novel method for late-stage skeletal reorganization (LSSR) of limonoid natural products through photochemical cascades. Nine distinct limonoid products with five unprecedented scaffolds are generated from xyloelves A and B. Quantum mechanical calculations reveal the photocascade pathways and mechanistic rationale of these natural products. Notably, a UV light-driven transannular and stereoselective C -> C 1,4-acyl migration is discovered as a photochemical approach for LSSR, which shows potential for accessing bioactive cage-like molecules. Additionally, the findings provide a proof of concept for natural product photobiosynthesis, and xyloelf A can be used as a molecular template for hepatoprotective drug discovery.
Article
Chemistry, Multidisciplinary
Wei Zhang, Li-Li Liao, Li Li, Yi Liu, Long-Fei Dai, Guo-Quan Sun, Chuan-Kun Ran, Jian-Heng Ye, Yu Lan, Da-Gang Yu
Summary: The dicarboxylation of unactivated skipped dienes with CO2 via electrochemistry is reported for the first time, providing valuable dicarboxylic acids. Control experiments and DFT calculations confirm the single electron transfer reduction of CO2 to its radical anion, followed by sluggish radical addition to unactivated alkenes, SET reduction of unstabilized alkyl radicals to carbanions, and nucleophilic attack on CO2 to give the desired products. This reaction possesses mild reaction conditions, broad substrate scope, facile derivations of products, and promising application in polymer chemistry.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Kangbao Zhong, Shihan Liu, Xiaoqian He, Hao Ni, Wei Lai, Wenting Gong, Chunhui Shan, Zhuang Zhao, Yu Lan, Ruopeng Bai
Summary: This report describes the oxidative cyclopalladation activation of a C =C bond during the Pd-catalyzed hydroalkylation of alkynes and analyzes potential reaction pathways based on density functional theory calculations. The more favorable pathway involves an oxidative cyclopalladation to generate a pallada-cyclopropene intermediate, which is rarely examined in Pd-catalyzed alkyne transformations. Theoretical calculations indicate covalent bonding between a Pd(II) center and the two C-atoms in three-membered palladacycle species. Finally, electrostatic potential analysis reveals that the regioselectivity is governed by the charge distribution on the palladacycle moiety during the protonation step.
CHINESE CHEMICAL LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Yumeng Shuai, Jianzhong Zhao, Renheng Bo, Yu Lan, Zengyao Lv, Yihui Zhang
Summary: Mechanically-guided three-dimensional assembly is a novel method for fabricating micro/nanoscale 3D structures and devices. It utilizes compressive buckling in a patterned high-modulus thin film integrated with a low-modulus elastomer substrate. To address the challenges of highly flexible 3D mesostructures or those with large-area suspended features, a wrinkling-assisted strategy is proposed to facilitate the delamination at desired regions. This strategy involves introducing an assisting layer with a weaker film/assisting-layer interface and utilizing wrinkles in the assisting layer to induce additional driving forces for separation.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Chemistry, Physical
Xinghua Wang, Kai Yang, Ya-Nan Wang, Shi-Jun Li, Donghui Wei, Yu Lan
Summary: Transition-metal-catalyzed transformation reactions of epoxides provide practical C2 synthons and a feasible strategy for catalyst-controlled divergent conversions. Understanding the crucial factors controlling chemoselectivity is key to rational design. Computational studies reveal that the chemoselective reaction can undergo a retro-[3 + 2] step or a carbonyl migration insertion step, influenced by the energy barriers and metal complexes configurations. These insights are important for understanding chemoselectivity and catalyst-controlled reactions.
Article
Multidisciplinary Sciences
Lei Peng, Zhen Zeng, Kai Li, Yidong Liu, Yu Lan, Hailong Yan
Summary: The catalytic dearomative cycloaddition of bicyclic heteroaromatics provides a rapid method for synthesizing functionalized heterocyclic molecules. This study presents a geometry-based differentiation approach to achieve regioselectivity in the cycloaddition of benzofurans and indoles. By controlling the rotation of a sigma bond at the C7 position, enantioenriched polycyclic compounds can be obtained from a racemic heterobiaryl. The mechanism of this parallel kinetic resolution was explained using density functional theory calculations. The bioactivity of the dearomatized products was evaluated, with some compounds exhibiting interesting biological activities.
Article
Chemistry, Physical
Xingchen Liu, Haohua Chen, Dali Yang, Binjing Hu, Ying Hu, Shengchun Wang, Yu Lan, Aiwen Lei, Jie Li
Summary: A multicomponent sulfonylation reaction using sulfonyl chlorides and OPiv-supported organozinc reagents was achieved via cobalt-catalyzed alkene difunctionalizations. Anion-coordination played a critical role in modifying the reactivity and chemical properties of organozinc reagents. The OPiv-coordination resulted in the lower reducibility of arylzinc pivalates, allowing for the in situ formation of catalytically relevant Co(I) species as the active catalyst in carbosulfonylation reactions.
Article
Chemistry, Organic
Kai Yang, Jiabin Liu, Dongmin Fu, Linbin Niu, Shi-Jun Li, Yu Lan
Summary: A radical relay model was developed for cross-coupling reactions involving multi-radical systems. The regio- and chemoselectivity of radical addition processes were examined using the photosensitized difunctionalization of styrene with oxime carbonate as a model reaction. In this model mechanism, a photosensitizer molecule absorbs a photon to generate an excited state, which then undergoes a triplet-triplet energy transfer process to produce an excited oxime carbonate intermediate. The chemoselectivity of the cross-coupling reaction is determined by variations in the relative concentrations of the two radical species.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Rong Fan, Shihan Liu, Qiang Yan, Yun Wei, Jingwen Wang, Yu Lan, Jiajing Tan
Summary: Boronic acids are widely used reagents in organic synthesis, and this study demonstrates their potential as efficient substitutes for hydroxides when activated through fluoride complexation. The researchers developed a novel reaction involving aryne-induced ring-opening of cyclic sulfides and three-component coupling of fluoro-azaarenes to showcase this application. The novel hydroxy source exhibits mild activation conditions, useful functionality tolerance, and structural tunability, offering new possibilities for organoboron chemistry. Detailed computational studies shed light on the mechanistic pathway and reactivity differences of ArB(OH)(x)F-y complexes, supporting the experimental data.
Article
Chemistry, Organic
Qianqian Shi, Kuohong Chen, Limin Guo, Lili Han, Donghui Wei, Yu Lan
Summary: In this study, the possible mechanisms of a series of deaminative radical reaction models have been investigated, revealing the existence of relayed proton-coupled electron transfer (relayed-PCET) mechanism instead of the commonly accepted single-electron transfer (SET) mechanism. Various deaminative radicals, including alkyl radicals, trifluoromethyl radicals, N-centered radicals, O-centered radicals, and other related radicals, are formed through homolysis of N-X (X = C, O, N) bonds. The exact orbital overlap pictures associated with different interaction modes and electron localization function (ELF) analysis provide insights into the nature of these deaminative radical reactions. This work is critical for understanding the general principle and detailed mechanism of deaminative radical reactions.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Jiangliang Yin, Jian Li, Haohua Chen, Ya Wang, Yuming Zhang, Cheng Zhang, Zhengyang Bin, Daniel Pyle, Yudong Yang, Yu Lan, Jingsong You
Summary: This study reports a programmable zigzag pi-extension strategy based on rhodium-catalysed sequential C2-H and C8-H activation-annulation of naphthalene ketones for rapid assembly of graphene-like molecules. This strategy uses acetylenedicarboxylates as the C2 insertion unit and selectively extends the naphthalene fragment through C(sp3)-H cyclization. The synthesis of related products such as anthanthrene and peri-naphthacenonaphthacene is successfully achieved.
