A rhodium-catalyzed desymmetrization reaction for enantioselective methyl C-H arylation is achieved by utilizing an in situ arylating reagent via nucleophilic cyclization of o-aminoaryl alkyne.The reaction results in ...A rhodium-catalyzed desymmetrization reaction for enantioselective methyl C-H arylation is achieved by utilizing an in situ arylating reagent via nucleophilic cyclization of o-aminoaryl alkyne.The reaction results in chiral indoles containing all-carbon quaternary stereocenters under atmospheric conditions,with a wide range of substrates exhibiting good enantioselectivity(44 examples).Mechnism and DFT studies show that the stereocontrol is reasonably achieved through the collaborative control of a large silicon substituted chiral ligand and C-H···π,LP···πinteractions between aryl rings of the carboxylate group and the substrate.Control experiments demonstrate that Rh-aryl bond formation via in situ nucleophilic cyclization is more critical for reaction efficiency than via C-H activation of the nucleophilic cyclization byproduct.展开更多
An efficient and scalable electrochemical asymmetric protocol with metal-free catalysts and even without additional oxidants for the cross-dehydrogenative coupling reaction(CDC)of two C(sp^(3))-H bonds is reported.A s...An efficient and scalable electrochemical asymmetric protocol with metal-free catalysts and even without additional oxidants for the cross-dehydrogenative coupling reaction(CDC)of two C(sp^(3))-H bonds is reported.A series of aldehydes including natural products and various substrates containing C(sp^(3))-H bonds including xanthenes,acridines,cycloheptatrienes and even diarylmethane have been shown to undergo asymmetric CDC to afford a series of carbon-carbon bond coupling products with up to 94%yield and 98%ee.Mechanistic studies such as radical clock experiment suggest that the reaction proceeds via nucleophilic attack by enamine under electrochemical conditions.展开更多
Catalytic C-H borylation is of prime topical importance,since easily available feedstock chemicals can thereby be transformed into valuable transient functional groups in the absence of directing groups.Herein,we disc...Catalytic C-H borylation is of prime topical importance,since easily available feedstock chemicals can thereby be transformed into valuable transient functional groups in the absence of directing groups.Herein,we disclose an iron-catalyzed C(sp^(3))-H borylation of simple,non-prefunctionalized alkanes,providing access to value-added products in a single step by means of photoelectrochemistry.The power of merging photo-and electrochemistry was mirrored by ample scope and exceedingly mild reaction conditions.Moreover,an outstanding position-selectivity in favor of primary C(sp^(3))-H proved viable within the photoelectrochemical borylation through a chemo-selective anodic overoxidation manifold.The ferro-photoelectrochemistry strategy avoids toxic precious transition metals,enabling C(sp^(3))-H borylations in a site-selective fashion.展开更多
An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been developed.This...An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been developed.This approach provides viable access to various 5-(quinolin-2-yl)isothiazoles in moderate to good yields with good functional group tolerance.Moreover,the success of the gram-scale reaction gives this reaction a great potential application.展开更多
Hydrogen atom transfer(HAT)is an elementary mechanistic step in organic synthesis.The photoredox-catalyzed HAT has transformed organic synthesis by enabling the activation and subsequent cross-coupling of traditionall...Hydrogen atom transfer(HAT)is an elementary mechanistic step in organic synthesis.The photoredox-catalyzed HAT has transformed organic synthesis by enabling the activation and subsequent cross-coupling of traditionally inert yet ubiquitous C(sp^(3))-H bonds.展开更多
By employing a readily available CuCI/DDQ catalyst system,we herein report a direct C(sp^(3))-H sulfonylation of xanthene derivates with odorless sodium sulfinates.Various 9H-xanthenes,thioxanthenes,and 9,10-dihydroac...By employing a readily available CuCI/DDQ catalyst system,we herein report a direct C(sp^(3))-H sulfonylation of xanthene derivates with odorless sodium sulfinates.Various 9H-xanthenes,thioxanthenes,and 9,10-dihydroacridines are efficiently transformed into the desired benzylic sulfonyl products via a radical/radical cross-coupling process,proceeding with the merits of broad substrate scope,operational simplicity,good functional group compatibility,and mild reaction conditions.展开更多
The isoindolinone and biaryl scaffolds are prevalent in natural products and drug molecules,which have showed broad and interesting biological activities.The efficient construction of such hybridized molecules and bio...The isoindolinone and biaryl scaffolds are prevalent in natural products and drug molecules,which have showed broad and interesting biological activities.The efficient construction of such hybridized molecules and biological evaluation are of great interest to medicinal chemistry community.In this communication,we report an efficient BrΦnsted acid-promoted C(sp^3)-H functionalization approach that enables the rapid construction of biologically important isoindolinone/[1,2,4]triazolo[1,5-a]pyrimidine hybrids from 5-methyl-7-(2,4,6-trimethoxyphenyl)-[1,2,4]triazolo[1,5-a]pyrimidine,2-formylbenzoic acid and various anilines.The title compounds were generated in high to excellent yields(up to 96%)regardless of the electronic nature and steric effects of the substituents.In this reaction,an isoindolinone scaffold,one C-C single bond,and two C-N bonds were formed simultaneously with high atom economy.In this work,we have envisioned that the methyl group linked to the electron-deficient Nheterocycles could be used as a new synthetic handle for late-state diversification and may have broad applications in the field of organic and medicinal chemistry.Besides,the title compounds have exhibited promising activity against the SKP2-CKS1 interaction.展开更多
Thioether skeletons are widely present in drugs,natural products,functional materials,and life science.In the past decade,the selective C–H functionalization of thioethers has been extensively studied to construct no...Thioether skeletons are widely present in drugs,natural products,functional materials,and life science.In the past decade,the selective C–H functionalization of thioethers has been extensively studied to construct novel thioether derivatives.This mini-review systematically introduces the recent advances in the field of the directα-C(sp^(3))-H functionalization of thioethers.展开更多
Metal-free direct α-C(sp^(3))-H intramolecular cyclization of 2-alkylthiobenzoic acid in the presence of Selectfluor is described.This novel strategy provides a facile and efficient method to access important 1,3-ben...Metal-free direct α-C(sp^(3))-H intramolecular cyclization of 2-alkylthiobenzoic acid in the presence of Selectfluor is described.This novel strategy provides a facile and efficient method to access important 1,3-benzooxathiin-4-one derivatives with good functional groups tolerance and yields.展开更多
Reported herein is the first example of heterogeneous palladium catalyzed C(sp^(3))-H bonds arylation by a transient-ligand-directed strategy.Using supported palladium(metallic state) na nopariticles as catalyst,a wid...Reported herein is the first example of heterogeneous palladium catalyzed C(sp^(3))-H bonds arylation by a transient-ligand-directed strategy.Using supported palladium(metallic state) na nopariticles as catalyst,a wide range of aryl iodides undergo the coupling with various o-methylbenzaldehyde derivatives to assemble a library of highly selective and functionalized o-benzylbenzaldehydes.The stability of the catalyst was easily recovered four runs without significant loss of activity.The XPS analysis of the catalyst before and after reaction indicated that the reaction might be carried out by a catalytic cycle starting with Pd~0.展开更多
Comprehensive Summary Developing new catalysts for highly selectivity and conversion of saturated C(sp^(3))-H bonds is of great significance.In order to obtain catalysts with high catalytic performance,six Eu-based MO...Comprehensive Summary Developing new catalysts for highly selectivity and conversion of saturated C(sp^(3))-H bonds is of great significance.In order to obtain catalysts with high catalytic performance,six Eu-based MOFs with different structural characteristics were obtained by using europium ions and different organic acid ligands,namely Eu-1~Eu-6.Eu-1,Eu-2 and Eu-3 featured three-dimensional structures,while Eu-4 and Eu-5 featured two-dimensional structures.展开更多
基金financial support for this work from the National Key R&D Program of China(No.2021YFC0864700)the National Natural Science Foundation of China(Nos.21801066,U1804283 and 82130103)+2 种基金the Central Plains Scholars and Scientists Studio Fund(No.2018002)the project funded by the Natural Science Foundation of Henan(Nos.222300420056,222300420204)the China Postdoctoral Science Foundation(Nos.2020M682307,2021T140183)。
文摘A rhodium-catalyzed desymmetrization reaction for enantioselective methyl C-H arylation is achieved by utilizing an in situ arylating reagent via nucleophilic cyclization of o-aminoaryl alkyne.The reaction results in chiral indoles containing all-carbon quaternary stereocenters under atmospheric conditions,with a wide range of substrates exhibiting good enantioselectivity(44 examples).Mechnism and DFT studies show that the stereocontrol is reasonably achieved through the collaborative control of a large silicon substituted chiral ligand and C-H···π,LP···πinteractions between aryl rings of the carboxylate group and the substrate.Control experiments demonstrate that Rh-aryl bond formation via in situ nucleophilic cyclization is more critical for reaction efficiency than via C-H activation of the nucleophilic cyclization byproduct.
基金National Natural Science Foundation of China(Nos.22161008,22061003)Guangxi Science and Technology Base and Talent Project(High Level Innovative Talents and Team Training)(Guike No.AD23026094)Guangxi Natural Science Foundation of China(No.2021GXNSFFA220005)for financial support。
文摘An efficient and scalable electrochemical asymmetric protocol with metal-free catalysts and even without additional oxidants for the cross-dehydrogenative coupling reaction(CDC)of two C(sp^(3))-H bonds is reported.A series of aldehydes including natural products and various substrates containing C(sp^(3))-H bonds including xanthenes,acridines,cycloheptatrienes and even diarylmethane have been shown to undergo asymmetric CDC to afford a series of carbon-carbon bond coupling products with up to 94%yield and 98%ee.Mechanistic studies such as radical clock experiment suggest that the reaction proceeds via nucleophilic attack by enamine under electrochemical conditions.
基金the European Research Council(ERC Advanced Grantno.101021358)+2 种基金the Deutsche Forschungsgemeinschaft(DFG,Gottfried Wilhelm Leibniz award to L.A.)the Fonds der Chemischen Industrie(FCI,Kekulé-Fellowship to T.v.M.)the China Scholarship Council(CSC grant no.201906280067 to W.W.).
文摘Catalytic C-H borylation is of prime topical importance,since easily available feedstock chemicals can thereby be transformed into valuable transient functional groups in the absence of directing groups.Herein,we disclose an iron-catalyzed C(sp^(3))-H borylation of simple,non-prefunctionalized alkanes,providing access to value-added products in a single step by means of photoelectrochemistry.The power of merging photo-and electrochemistry was mirrored by ample scope and exceedingly mild reaction conditions.Moreover,an outstanding position-selectivity in favor of primary C(sp^(3))-H proved viable within the photoelectrochemical borylation through a chemo-selective anodic overoxidation manifold.The ferro-photoelectrochemistry strategy avoids toxic precious transition metals,enabling C(sp^(3))-H borylations in a site-selective fashion.
基金Support by the National Natural Science Foundation of China(Nos.22271244,21871226 and 21572194)Postgraduate Scientific Research Innovation Project of Hunan Province(No.CX20200631)the Open Research Fund of the School of Chemistry and Chemical Engineering of Henan Normal University(No.2022C02)is gratefully acknowledged.
文摘An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been developed.This approach provides viable access to various 5-(quinolin-2-yl)isothiazoles in moderate to good yields with good functional group tolerance.Moreover,the success of the gram-scale reaction gives this reaction a great potential application.
基金We are grateful for financial support from the National Key R&D Program of China(2021YFA1502500)National Natural Science Foundation of China(22071203)Fundamental Research Funds for the Central Universities(20720210014).
文摘Hydrogen atom transfer(HAT)is an elementary mechanistic step in organic synthesis.The photoredox-catalyzed HAT has transformed organic synthesis by enabling the activation and subsequent cross-coupling of traditionally inert yet ubiquitous C(sp^(3))-H bonds.
基金the National Natural Science Foundation of China(No.21971071)the Natural Science Foundation of Guangdong Province(No.2021A1515010155)the Fundamental Research Funds for the Central Universities(No.2020ZYGXZR075).
文摘By employing a readily available CuCI/DDQ catalyst system,we herein report a direct C(sp^(3))-H sulfonylation of xanthene derivates with odorless sodium sulfinates.Various 9H-xanthenes,thioxanthenes,and 9,10-dihydroacridines are efficiently transformed into the desired benzylic sulfonyl products via a radical/radical cross-coupling process,proceeding with the merits of broad substrate scope,operational simplicity,good functional group compatibility,and mild reaction conditions.
基金supported by the National Natural Science Foundation of China(Nos.81773562 and 81703326)China Postdoctoral Science Foundation(Nos.2018M630840 and 2019T120641)Scientific Program of Henan Province(No.182102310123)。
文摘The isoindolinone and biaryl scaffolds are prevalent in natural products and drug molecules,which have showed broad and interesting biological activities.The efficient construction of such hybridized molecules and biological evaluation are of great interest to medicinal chemistry community.In this communication,we report an efficient BrΦnsted acid-promoted C(sp^3)-H functionalization approach that enables the rapid construction of biologically important isoindolinone/[1,2,4]triazolo[1,5-a]pyrimidine hybrids from 5-methyl-7-(2,4,6-trimethoxyphenyl)-[1,2,4]triazolo[1,5-a]pyrimidine,2-formylbenzoic acid and various anilines.The title compounds were generated in high to excellent yields(up to 96%)regardless of the electronic nature and steric effects of the substituents.In this reaction,an isoindolinone scaffold,one C-C single bond,and two C-N bonds were formed simultaneously with high atom economy.In this work,we have envisioned that the methyl group linked to the electron-deficient Nheterocycles could be used as a new synthetic handle for late-state diversification and may have broad applications in the field of organic and medicinal chemistry.Besides,the title compounds have exhibited promising activity against the SKP2-CKS1 interaction.
基金support from the National Natural Science Foundation of China(NSFC,No.21702019)and Advanced Catalysis and Green Manufacturing Collaborative Innovation Center,Changzhou UniversityHaibo Ge,Mazen Elsaid and Chong Liu acknowledge NSF(No.CHE-2029932),Robert A.Welch Foundation(No.D-2034-20200401),and the Texas Tech University for financial support.
文摘Thioether skeletons are widely present in drugs,natural products,functional materials,and life science.In the past decade,the selective C–H functionalization of thioethers has been extensively studied to construct novel thioether derivatives.This mini-review systematically introduces the recent advances in the field of the directα-C(sp^(3))-H functionalization of thioethers.
基金the financial support from the National Natural Science Foundation of China(Nos.21572026,21702019)Advanced Catalysis and Green Manufacturing Collaborative Innovation Center,Changzhou University。
文摘Metal-free direct α-C(sp^(3))-H intramolecular cyclization of 2-alkylthiobenzoic acid in the presence of Selectfluor is described.This novel strategy provides a facile and efficient method to access important 1,3-benzooxathiin-4-one derivatives with good functional groups tolerance and yields.
基金financially supported by the National Natural Science Foundation of China(No.21861030)the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT-17-A22)。
文摘Reported herein is the first example of heterogeneous palladium catalyzed C(sp^(3))-H bonds arylation by a transient-ligand-directed strategy.Using supported palladium(metallic state) na nopariticles as catalyst,a wide range of aryl iodides undergo the coupling with various o-methylbenzaldehyde derivatives to assemble a library of highly selective and functionalized o-benzylbenzaldehydes.The stability of the catalyst was easily recovered four runs without significant loss of activity.The XPS analysis of the catalyst before and after reaction indicated that the reaction might be carried out by a catalytic cycle starting with Pd~0.
基金supported by Changsha Municipal Natural Science Foundation(kq2014164)the Natural Science Foundation of Hunan Province(Grant 2020JJ4684)Science and Technology Innovation Project of Hunan Academy of Agricultural Sciences(2020CX45).
文摘Comprehensive Summary Developing new catalysts for highly selectivity and conversion of saturated C(sp^(3))-H bonds is of great significance.In order to obtain catalysts with high catalytic performance,six Eu-based MOFs with different structural characteristics were obtained by using europium ions and different organic acid ligands,namely Eu-1~Eu-6.Eu-1,Eu-2 and Eu-3 featured three-dimensional structures,while Eu-4 and Eu-5 featured two-dimensional structures.
