A blue light-induced formal insertion reaction ofα-siloxy carbene into the C—H bond of 1,3-diketones has been reported.Under the irradiation of blue light,acylsilane converts toα-siloxy carbene,which then undergoes...A blue light-induced formal insertion reaction ofα-siloxy carbene into the C—H bond of 1,3-diketones has been reported.Under the irradiation of blue light,acylsilane converts toα-siloxy carbene,which then undergoes formal C—H bond insertion reaction with the enol form of 1,3-diketone.This method uses readily available and relative stable acylsilane as car-bene precursor,which features a simple and metal-free approach under mild conditions.Moreover,the synthetic potential of this protocol has been demonstrated by performing the reaction on a gram scale with comparable high yield.展开更多
Direct enantioselective allylic C—H functionalization has emerged as a powerful strategy for the asymmetric syn-thesis of highly valuable chiral products.Herein,a Rh(III)-catalyzed enantioselective allylic C—H alkyl...Direct enantioselective allylic C—H functionalization has emerged as a powerful strategy for the asymmetric syn-thesis of highly valuable chiral products.Herein,a Rh(III)-catalyzed enantioselective allylic C—H alkylation of unactivated alkenes withα-diazo carbonyl compounds is described,enabling direct access to chiral products with high efficiency(up to 77%yield,92%ee,and>10∶1 B/L(branched/linear)selectivity).This atom-and step-economical protocol directly converts simple,unactivated substrates into valuable enantioenriched products under mild conditions,providing an efficient catalytic system for asymmetric allylic C—H functionalization.展开更多
Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strateg...Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle.展开更多
The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundan...The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundance of hydrocarbon compounds,and the potential for late-stage functionalization of complex organic molecules.The ortho-and meta-C-H activation and functionalization of aromatic compounds have been widely explored in recent years,however the distal para-C-H activation and functionalization has remained a significant challenge because of the difficulty in forming energetically favorable metallacyclic transition states.The utilization of appropriate directing groups or templates as well as the meticulous design of catalysts and ligands has proven to be effective in transition-metal-catalyzed remote para-C-H bonds activation and functionalization of aromatic compounds.This review aims to summarize the strategies for controlling para-selective C–H functionalization using the directing group,template engineering,and catalyst/ligand design under transition metals catalysis in recent years.展开更多
Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,th...Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,the catalysts employed in homogeneous catalysis are generally expensive,sensitive,and difficult to separate from the reaction mixture and reuse.With the rapid development of heterogeneous catalysis,heterogeneous C-H and C-X borylation have emerged as highly efficient and sustainable approaches towards the synthesis of organoboron compounds.This review aims to highlight the recent advances in the synthesis of organoboron compounds employing heterogeneous C-H and C-X borylation strategies.We endeavor to shed light on new perspectives and inspire further research and applications in this emerging area.展开更多
Photocatalytic activation of C-H bonds is versatile but challenging for undergoing oriented conversion processes.Herein,a spatially site-isolated heterojunction(ZS-Vs/ZIS)of ZnIn2S4 with strong Lewis acidity(ZIS)and Z...Photocatalytic activation of C-H bonds is versatile but challenging for undergoing oriented conversion processes.Herein,a spatially site-isolated heterojunction(ZS-Vs/ZIS)of ZnIn2S4 with strong Lewis acidity(ZIS)and ZnS with S-vacancy(ZS-Vs)is constructed for activating α-C‒H bond and forming·O_(2)^(-)to cleave the C-H bond,respectively.ZS-Vs/ZIS displays outstanding performance in visible-light partial photooxidation of bio-based 5-hydroxymethylfurfural(HMF)to 2,5-diformylfuran(DFF)in an unprecedented yield of 95.7%at 25°C.In-situ experiments and calculations reveal that Zn sites of ZIS serve as hole enrichment to adsorb HMF for α-C‒H activation via ligand-to-metal charge transfer.Shallow trap states introduced by S-vacancy in ZS-Vs act as an electron pool to realize directed O_(2) activation into·O_(2)^(-)for breaking pre-activated α-C‒H bond in HMF to exclusively give DFF.Moreover,ZS-Vs/ZIS has good recyclability and universality in the photooxidation of various alcohols to carbonyls(86.4-95.6%yields).The synergistic C-H activation/breaking strategy exhibits high potential in targeted photocatalytic transformations.展开更多
An electronic circular dichroism(ECD)-based chiroptical sensing method has been developed forβ-andγ-chiral primary amines via a C-H activation reaction.With the addition of Pd(OAc)_(2),the flexible remote chiral pri...An electronic circular dichroism(ECD)-based chiroptical sensing method has been developed forβ-andγ-chiral primary amines via a C-H activation reaction.With the addition of Pd(OAc)_(2),the flexible remote chiral primary amine fragment in the bidentate ligand intermediate was fixed to form a cyclopalladium complex,producing an intense ECD response.The correlation between the sign of Cotton effects and the absolute configuration of substrates was proposed,together with theoretical verification using timedependent density functional theory(TDDFT).Chiroptical sensing of an important drug raw material was performed to provide rapid and accurate information on the absolute optical purity.This work introduces an alternative perspective of C-H activation reaction as well as a feasible chiroptical sensing method of remote chiral amines.展开更多
文摘A blue light-induced formal insertion reaction ofα-siloxy carbene into the C—H bond of 1,3-diketones has been reported.Under the irradiation of blue light,acylsilane converts toα-siloxy carbene,which then undergoes formal C—H bond insertion reaction with the enol form of 1,3-diketone.This method uses readily available and relative stable acylsilane as car-bene precursor,which features a simple and metal-free approach under mild conditions.Moreover,the synthetic potential of this protocol has been demonstrated by performing the reaction on a gram scale with comparable high yield.
文摘Direct enantioselective allylic C—H functionalization has emerged as a powerful strategy for the asymmetric syn-thesis of highly valuable chiral products.Herein,a Rh(III)-catalyzed enantioselective allylic C—H alkylation of unactivated alkenes withα-diazo carbonyl compounds is described,enabling direct access to chiral products with high efficiency(up to 77%yield,92%ee,and>10∶1 B/L(branched/linear)selectivity).This atom-and step-economical protocol directly converts simple,unactivated substrates into valuable enantioenriched products under mild conditions,providing an efficient catalytic system for asymmetric allylic C—H functionalization.
基金2024 Special Talent Introduction Projects of Key R&D Program of Ningxia Hui Autonomous Region(2024BEH04049)the 2024 Guyuan City Innovation-Driven Achievement Transformation Project(2024BGTYF01-47)2025 Ningxia Natural Science Foundation Program(2025AAC030624).
文摘Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle.
基金support from the National Natural Science Foundation of China(No.21901206)Postdoctoral Science Foundation of China(No.2022M712589)+2 种基金General Key R&D Projects in Shaanxi Province(No.2023-YBGY-321)Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-MSX0826)National&Local Joint Engineering Research Center for mineral Salt Deep Utilization,Huaiyin Institute of Technology(No.SF202407)for financial support。
文摘The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundance of hydrocarbon compounds,and the potential for late-stage functionalization of complex organic molecules.The ortho-and meta-C-H activation and functionalization of aromatic compounds have been widely explored in recent years,however the distal para-C-H activation and functionalization has remained a significant challenge because of the difficulty in forming energetically favorable metallacyclic transition states.The utilization of appropriate directing groups or templates as well as the meticulous design of catalysts and ligands has proven to be effective in transition-metal-catalyzed remote para-C-H bonds activation and functionalization of aromatic compounds.This review aims to summarize the strategies for controlling para-selective C–H functionalization using the directing group,template engineering,and catalyst/ligand design under transition metals catalysis in recent years.
基金supported by grants from the National Natural Science Foundation of China(Nos.22271313,21602096)the Fund for Academic Innovation Teams of South-Central Minzu University(No.XTZ24015)South-Central Minzu University.
文摘Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,the catalysts employed in homogeneous catalysis are generally expensive,sensitive,and difficult to separate from the reaction mixture and reuse.With the rapid development of heterogeneous catalysis,heterogeneous C-H and C-X borylation have emerged as highly efficient and sustainable approaches towards the synthesis of organoboron compounds.This review aims to highlight the recent advances in the synthesis of organoboron compounds employing heterogeneous C-H and C-X borylation strategies.We endeavor to shed light on new perspectives and inspire further research and applications in this emerging area.
基金supported by the National Natural Science Foundation of China(22478087,22368014)Guizhou Provincial S&T Project(GCC[2023]011,ZK[2022]011)Guizhou Provincial Higher Education Institution Program(Qianjiaoji[2023]082).
文摘Photocatalytic activation of C-H bonds is versatile but challenging for undergoing oriented conversion processes.Herein,a spatially site-isolated heterojunction(ZS-Vs/ZIS)of ZnIn2S4 with strong Lewis acidity(ZIS)and ZnS with S-vacancy(ZS-Vs)is constructed for activating α-C‒H bond and forming·O_(2)^(-)to cleave the C-H bond,respectively.ZS-Vs/ZIS displays outstanding performance in visible-light partial photooxidation of bio-based 5-hydroxymethylfurfural(HMF)to 2,5-diformylfuran(DFF)in an unprecedented yield of 95.7%at 25°C.In-situ experiments and calculations reveal that Zn sites of ZIS serve as hole enrichment to adsorb HMF for α-C‒H activation via ligand-to-metal charge transfer.Shallow trap states introduced by S-vacancy in ZS-Vs act as an electron pool to realize directed O_(2) activation into·O_(2)^(-)for breaking pre-activated α-C‒H bond in HMF to exclusively give DFF.Moreover,ZS-Vs/ZIS has good recyclability and universality in the photooxidation of various alcohols to carbonyls(86.4-95.6%yields).The synergistic C-H activation/breaking strategy exhibits high potential in targeted photocatalytic transformations.
基金supported by the CAMS Innovation Fund for Medical Sciences(CIFMS,No.2023-I2M-2-009).
文摘An electronic circular dichroism(ECD)-based chiroptical sensing method has been developed forβ-andγ-chiral primary amines via a C-H activation reaction.With the addition of Pd(OAc)_(2),the flexible remote chiral primary amine fragment in the bidentate ligand intermediate was fixed to form a cyclopalladium complex,producing an intense ECD response.The correlation between the sign of Cotton effects and the absolute configuration of substrates was proposed,together with theoretical verification using timedependent density functional theory(TDDFT).Chiroptical sensing of an important drug raw material was performed to provide rapid and accurate information on the absolute optical purity.This work introduces an alternative perspective of C-H activation reaction as well as a feasible chiroptical sensing method of remote chiral amines.
基金Project supported by the Department of Henan Province Natural Science and Technology Foundation(Nos.172102210225 and 182102310675)the Natural Science Foundation in Henan Province Department of Education(No.17A150005)+1 种基金the Program for Innovative Research Team from Zhengzhou(No.131PCXTD605)the Project of Youth Backbone Teachers of Henan University of Technology(No.2016003)~~
