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
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
In recent years,the transition metal-free sulfenylation of C-H bond for C-S formation has been rapidly advanced and has become an eco-friendly synthetic tool for pharmacists and organic chemists.Various natural or bio...In recent years,the transition metal-free sulfenylation of C-H bond for C-S formation has been rapidly advanced and has become an eco-friendly synthetic tool for pharmacists and organic chemists.Various natural or bioactive molecules such as(hetero)arenes,olefins,carbonyl compounds,alkanes,have been employed for sulfenylating reactions.This review will focus on the recent five-year advances in C-S bond formation via direct sulfenylation of C(sp^3)-H bonds under metal-free conditions and elaborate their mechanisms from a new perspective.展开更多
Oximes derivatives have been vastly used in organic synthesis. In this review, C(sp^(3))-H bond functionalization of oximes derivatives via iminyl radical induced 1,5-hydrogen atom transfer was discussed. According to...Oximes derivatives have been vastly used in organic synthesis. In this review, C(sp^(3))-H bond functionalization of oximes derivatives via iminyl radical induced 1,5-hydrogen atom transfer was discussed. According to the different type of products, this review was divided into three parts: (1) C(sp^(3))-H bond functionalization for C-C bond formation. (2) C(sp^(3))-H bond functionalization for C-N bond formation. (3) C(sp^(3))-H bond functionalization for C-S, C-F bond formation.展开更多
Photoredox catalysis can be induced to activate organic substrates or to modulate the oxidation state of transition-metal catalysts via unique singleelectron transfer processes,so as to achieve challenging C(sp^(3))-H...Photoredox catalysis can be induced to activate organic substrates or to modulate the oxidation state of transition-metal catalysts via unique singleelectron transfer processes,so as to achieve challenging C(sp^(3))-H functionalization under mild conditions.However,the specific reaction mechanism and relevant electron transfer process still need to be clarified.Here,a highly regioselective Ir^(Ⅲ)/Ni^(Ⅱ)-metallaphotoredox-catalyzed hydroalkylation of asymmetrical internal alkyne with an etherα-hetero C(sp^(3))-H bond has been investigated by density functional theory(DFT)calculations.A novel radical mechanism was predicted to merge oxidative quenching(Ir^(Ⅲ)-*Ir^(Ⅲ)-Ir^(Ⅳ)-Ir^(Ⅲ))and nickel catalytic cycles(NiⅡ-NiⅢ-NiI-NiⅢ-NiⅡ)for this C(sp^(3))-H functionalization to construct C(sp^(3))-C(sp^(2))bonds.It consists of seven major steps:the single-electron transfer involved in the photoredox cycle for generating active Ni(Ⅰ)-chloride complexes,proton-coupled electron transfer process to provide α-carbon-centered tetrahydrofuran(THF)radicals,radical capture by Ni(Ⅱ),reductive elimination to obtain 2-chlorotetrahydrofuran,alkyne oxidative hydrometallation,innersphere electron transfer,and σ-bond metathesis to yield the desired alkyne hydroalkylation product.Importantly,both the thermodynamic performance for redox potentials and the kinetic exploration for energy barriers and electron-transfer rates have also been evaluated for the corresponding electron transfer processes.In addition,the steric effects play a major role in determining the regioselectivity of alkyne oxidative hydrometallation.展开更多
A method of C（sp^3）-H bond functionalization of methyl azaarenes catalyzed by alumina-supported heteropoly acid and addition to isatins was developed. This transformation could be used for the synthesis of biologica...A method of C（sp^3）-H bond functionalization of methyl azaarenes catalyzed by alumina-supported heteropoly acid and addition to isatins was developed. This transformation could be used for the synthesis of biologically important 3-hydroxy-2-oxindole derivatives in good to excellent yields and the catalyst could be reused for six times without significant decrease in activity.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
A new method for post-assembly modification of peptides via the Pd-catalyzed endogenous group-directed sp^(3) C—H arylation with aryl iodides is developed.The sulfide side chain of methionine(Met)residue can facilita...A new method for post-assembly modification of peptides via the Pd-catalyzed endogenous group-directed sp^(3) C—H arylation with aryl iodides is developed.The sulfide side chain of methionine(Met)residue can facilitate the arylation of bothβandγmethyl C—H bonds of N-terminal aliphatic amino acids of peptides via formation of 5 or 6-membered palladacycle intermediates.The reactions can proceed in moderate to good yield and with excellent diastereoselectivity.展开更多
Direct functionalization of inert C(sp^(3))–H bonds is a topic of immense contemporary interest and exceptional value in organic synthesis.The recent research has established a novel and practical protocol which feat...Direct functionalization of inert C(sp^(3))–H bonds is a topic of immense contemporary interest and exceptional value in organic synthesis.The recent research has established a novel and practical protocol which features the engagement of vinyl cation species to functionalize C(sp^(3))–H bonds.The discussion of the topic is arranged by the strategies to generate the reactive intermediates,including ionization of vinyl triflates,addition of electrophiles to alkynes,tandem cyclization of enynes or diynes,and decomposition ofβ-hydroxy-α-diazo ketones.This review closes with a personal perspective on the dynamic research area of unactivated C(sp^(3))–H functionalization via vinyl cations.Hopefully,it will provide timely illumination and beneficial guidance for organic chemists who are interested in this area.Meanwhile continued development of the field is strongly anticipated in the future.展开更多
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.
基金financial support from the Young Scholars Research Fund of Yantai University (No.HY19B06)
文摘In recent years,the transition metal-free sulfenylation of C-H bond for C-S formation has been rapidly advanced and has become an eco-friendly synthetic tool for pharmacists and organic chemists.Various natural or bioactive molecules such as(hetero)arenes,olefins,carbonyl compounds,alkanes,have been employed for sulfenylating reactions.This review will focus on the recent five-year advances in C-S bond formation via direct sulfenylation of C(sp^3)-H bonds under metal-free conditions and elaborate their mechanisms from a new perspective.
基金supported by the National Natural Science Foundation of China (Nos. 21772107, 21901010)Shandong Province Key Research and Development Plan (No. 2019GSF108017)。
文摘Oximes derivatives have been vastly used in organic synthesis. In this review, C(sp^(3))-H bond functionalization of oximes derivatives via iminyl radical induced 1,5-hydrogen atom transfer was discussed. According to the different type of products, this review was divided into three parts: (1) C(sp^(3))-H bond functionalization for C-C bond formation. (2) C(sp^(3))-H bond functionalization for C-N bond formation. (3) C(sp^(3))-H bond functionalization for C-S, C-F bond formation.
文摘Photoredox catalysis can be induced to activate organic substrates or to modulate the oxidation state of transition-metal catalysts via unique singleelectron transfer processes,so as to achieve challenging C(sp^(3))-H functionalization under mild conditions.However,the specific reaction mechanism and relevant electron transfer process still need to be clarified.Here,a highly regioselective Ir^(Ⅲ)/Ni^(Ⅱ)-metallaphotoredox-catalyzed hydroalkylation of asymmetrical internal alkyne with an etherα-hetero C(sp^(3))-H bond has been investigated by density functional theory(DFT)calculations.A novel radical mechanism was predicted to merge oxidative quenching(Ir^(Ⅲ)-*Ir^(Ⅲ)-Ir^(Ⅳ)-Ir^(Ⅲ))and nickel catalytic cycles(NiⅡ-NiⅢ-NiI-NiⅢ-NiⅡ)for this C(sp^(3))-H functionalization to construct C(sp^(3))-C(sp^(2))bonds.It consists of seven major steps:the single-electron transfer involved in the photoredox cycle for generating active Ni(Ⅰ)-chloride complexes,proton-coupled electron transfer process to provide α-carbon-centered tetrahydrofuran(THF)radicals,radical capture by Ni(Ⅱ),reductive elimination to obtain 2-chlorotetrahydrofuran,alkyne oxidative hydrometallation,innersphere electron transfer,and σ-bond metathesis to yield the desired alkyne hydroalkylation product.Importantly,both the thermodynamic performance for redox potentials and the kinetic exploration for energy barriers and electron-transfer rates have also been evaluated for the corresponding electron transfer processes.In addition,the steric effects play a major role in determining the regioselectivity of alkyne oxidative hydrometallation.
基金Financial support from the National Natural Science Foundation of China(No.21402103)the research fund of Qingdao Agricultural University's High-level Person(No.631303)the Scientific Research Foundation of Shandong Province Outstanding Young Scientist Award(No.BS2013YY024) were gratefully acknowledged
文摘A method of C（sp^3）-H bond functionalization of methyl azaarenes catalyzed by alumina-supported heteropoly acid and addition to isatins was developed. This transformation could be used for the synthesis of biologically important 3-hydroxy-2-oxindole derivatives in good to excellent yields and the catalyst could be reused for six times without significant decrease in activity.
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supported by the National Natural Science Foundation of China(21725204)Frontiers Science Center for New Organic Matter(63181206)Haihe Laboratory of Sustainable Chemical Transformations,and NCC2020FH02。
文摘A new method for post-assembly modification of peptides via the Pd-catalyzed endogenous group-directed sp^(3) C—H arylation with aryl iodides is developed.The sulfide side chain of methionine(Met)residue can facilitate the arylation of bothβandγmethyl C—H bonds of N-terminal aliphatic amino acids of peptides via formation of 5 or 6-membered palladacycle intermediates.The reactions can proceed in moderate to good yield and with excellent diastereoselectivity.
基金supported by the National Natural Science Foundation of China(21772161,21828102)the Natural Science Foundation of Fujian Province(2019J02001)+3 种基金the President Research Funds from Xiamen University(20720180036)NFFTBS(J1310024)the Foundation of Wenzhou Science&Technology Bureau(ZY2020027)the Science&Technology Co-operation Program of Xiamen(3502Z20183015)。
文摘Direct functionalization of inert C(sp^(3))–H bonds is a topic of immense contemporary interest and exceptional value in organic synthesis.The recent research has established a novel and practical protocol which features the engagement of vinyl cation species to functionalize C(sp^(3))–H bonds.The discussion of the topic is arranged by the strategies to generate the reactive intermediates,including ionization of vinyl triflates,addition of electrophiles to alkynes,tandem cyclization of enynes or diynes,and decomposition ofβ-hydroxy-α-diazo ketones.This review closes with a personal perspective on the dynamic research area of unactivated C(sp^(3))–H functionalization via vinyl cations.Hopefully,it will provide timely illumination and beneficial guidance for organic chemists who are interested in this area.Meanwhile continued development of the field is strongly anticipated in the future.
