Selective defluorinative functionalization of trifluoromethylarenes(ArCF3)to obtain the pharmaceutically commonα,α-difluorobenzylic motif is an attractive and elegant synthetic route.Over the past decade,although C(...Selective defluorinative functionalization of trifluoromethylarenes(ArCF3)to obtain the pharmaceutically commonα,α-difluorobenzylic motif is an attractive and elegant synthetic route.Over the past decade,although C(sp^(3))-F bonds functionalization have been greatly developed,catalytic cross-coupling of trifluoromethylarenes with C-H of terminal alkynes remains a challenge.Here,we report an approach to achieve Sonogashira-type cross-coupling of trifluoromethylarenes with terminal alkynes C(sp)-H bonds via photoredox and Cu/L dual catalysis.Tridentate anionic ligand is pivotal to realize this C-H sp-sp^(3) cross-coupling.Moreover,this unique catalytic system is also suitable for cross-coupling of C(sp^(3))-F bonds with azoles C(sp^(2))-H bonds.A series of trifluoromethylarenes,terminal alkynes and azoles with various functional groups are compatible with this protocol affording a variety of defluoroalkynylation or defluoroazolation products.Preliminary mechanistic studies indicated that deprotonated BINOL involved as a photocatalyst to activate ArCF3 rather than a ligand to the metal.展开更多
Late-stage modification of complex molecules via site-selective hydrodefluorination is a challenging endeavor.The selective activation of carbon-fluorine(C-F) bonds in the presence of multiple C-F bonds is of importan...Late-stage modification of complex molecules via site-selective hydrodefluorination is a challenging endeavor.The selective activation of carbon-fluorine(C-F) bonds in the presence of multiple C-F bonds is of importance in organic synthesis and drug discovery.Herein,we describe the activation of C-F bonds via multiphoton photoredox catalysis to selectively produces a series of hydrodefluorinated compounds by simply tuning the reaction conditions.Moreover,this protocol was successfully applied to the late-stage functionalization of different drug-derivatives and the corresponding mono-,di-,and tri-defluorinated products were obtained in good to excellent yields.A detailed mechanistic investigation provides insight into the unprecedented hydrodefluorination pathway.展开更多
A photoredox-catalyzed synthesis ofα,α-difluoromethyl sulfones from sulfur dioxide with readily available gem–difluoroalkenes is reported.This protocol features mild reaction conditions,broad substrate scope and go...A photoredox-catalyzed synthesis ofα,α-difluoromethyl sulfones from sulfur dioxide with readily available gem–difluoroalkenes is reported.This protocol features mild reaction conditions,broad substrate scope and good functional group compatibility,giving rise to the targetα,α-difluoromethyl sulfones in moderate to excellent yields.Mechanistic studies indicate that this reaction is initiated by an aryl radical with the insertion of sulfur dioxide.展开更多
The radical difunctionalization of alkenes with sulfonyl bifunctional represents a powerful and straightforward approach to access functionalized alkane derivatives.However,both the mechanistic activation mode and the...The radical difunctionalization of alkenes with sulfonyl bifunctional represents a powerful and straightforward approach to access functionalized alkane derivatives.However,both the mechanistic activation mode and the substrate scopes of this type of radical difunctionalizations are still limited.We demonstrate herein a modular photoredox strategy for the difunctionalization of alkenes,employing arylsulfonyl acetate as the bifunctional reagent.This approach involves a radical addition/Smiles rearrangement cascade process,offering a robust alternative for the synthesis of valuableγ,γ-diaryl andγ-aryl esters.A complementary oxidative bifunctional reagents activation mode is identified to govern the radical cascade reactions,facilitating the simultaneous incorporation of aryl and carboxylate-bearing alkyl groups into the alkenes with excellent diastereoselectivity.Noteworthy features of this method include mild reaction conditions,organophotocatalysis,high atom-and step-economy,excellent functional group compatibility and great structural diversity.展开更多
The conversion of biomass into valuable chemicals has promise for application in biorefineries.Light-driven photoredox catalysis,with the typical features of green route and operation under mild conditions,is consider...The conversion of biomass into valuable chemicals has promise for application in biorefineries.Light-driven photoredox catalysis,with the typical features of green route and operation under mild conditions,is considered a promising strategy for renewable biomass or biomass-derived intermediates conversion into high-value-added chemical feedstocks.In this review,we strongly emphasize the recent advances in photocatalytic valorization of lignin model compounds and biomassderived alcohols.We briefl y summarize the advances in photocatalytic cleavage of theβ-O-4 bond or C–C bond into usable chemicals in the lignin model.On the other hand,we clarify not only the hybrid system for cooperative biomass-relevant alcohols oxidation and hydrogen(H2)evolution but also the tunable accessibility to variation of the target products from the same alcohol reactant by catalyst design and optimization of reaction conditions.It is hoped that this review will inspire the rational design of photoredox catalysis-based systems toward efficient biomass-derived platform molecules valorization to obtain target-oriented valuable products.展开更多
Visible light‐driven carboxylation with CO_(2) have emerged as a sustainable and powerful way to transfer waste to treasure.However,it is still challenging for aryl fluorides due to the low reactivities of both C(sp2...Visible light‐driven carboxylation with CO_(2) have emerged as a sustainable and powerful way to transfer waste to treasure.However,it is still challenging for aryl fluorides due to the low reactivities of both C(sp2)−F bonds and CO_(2).Herein,we report the first photocatalytic carboxylation of aryl C−F bonds with CO_(2).The visible‐light photoredox catalysis enables selective carboxylation of strong C(sp2)−F bonds in diverse polyluoroarenes,such as penta‐,tetra‐,and tri‐fluoroarenes under mild conditions,providing a facile access to a series of important polyfluoroaryl carboxylic acids with good yields.In contrast to previous reports of direct capture of polyfluoroaryl radicals,mechanistic studies suggest that the reduction of fleeting polyfluoroaryl radicals into polyfluoroaryl anions might be involved in this transformation,which may open a new avenue for photocatalytic functionalization of aryl C−F bonds.展开更多
The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation pr...The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high yields.Moreover,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.展开更多
An efficient and practical route to various 3-alkoxylquinoxalin-2(1 H)-ones through visible-light photocatalytic C(sp^2)-H/O-H cross-dehydrogenation coupling of quinoxalin-2(1 H)-ones and alcohols,employing ambient ai...An efficient and practical route to various 3-alkoxylquinoxalin-2(1 H)-ones through visible-light photocatalytic C(sp^2)-H/O-H cross-dehydrogenation coupling of quinoxalin-2(1 H)-ones and alcohols,employing ambient air as an oxidant at room temperature under metal-free conditions,was developed.展开更多
Glycosyl radicals,produced under mild photoredox conditions,show unique utility in the preparation of C-linked glycoconjugates.We herein report the construction of C-glycosidic bonds on α,β-dehydroalanine(DHA)of pep...Glycosyl radicals,produced under mild photoredox conditions,show unique utility in the preparation of C-linked glycoconjugates.We herein report the construction of C-glycosidic bonds on α,β-dehydroalanine(DHA)of peptides with easily available glycosyl bromides as glycosyl radical precursors under highly anomeric control,leading to C-glycosylation modifications of peptides.This method not only has outstanding functional group compatibility,but also is feasible in near-physiological conditions(pH~7 and temperature T≤37℃ in aqueous media).展开更多
Ternary composites of reduced graphene oxide(GR)-CdS-Pd have been successfully synthesized via solvothermal and photodeposition methods for photocatalytic selective conversion of benzyl alcohol(BA)coupled with hydroge...Ternary composites of reduced graphene oxide(GR)-CdS-Pd have been successfully synthesized via solvothermal and photodeposition methods for photocatalytic selective conversion of benzyl alcohol(BA)coupled with hydrogen(H_(2))production, which exhibit significantly improved photoactivity and selectivity than bare CdS. Mechanistic studies unveil that the cooperative effect of the close interface contact and matched energy level alignment between electrical conducting GR nanosheets(NSs) and CdS nanoparticles(NPs) in GR-CdS-Pd composite not only benefits the separation and transfer of photogenerated carriers but also improves the photocorrosion resistance of CdS. The photodeposited Pd NPs further promote the photogenerated charge separation and accelerate the formation of intermediate products(α-hydroxybenzyl radicals), thereby contributing to enhanced conversion of BA. This work would facilitate the rational design of GR as cocatalyst to construct an efficient and stable CdS-based composite photocatalyst for cooperative coupling of fine chemical synthesis and H_(2) evolution.展开更多
An efficient C–P bond formation reaction was developed by virtue of the synergetic catalysis strategy by merging heterogeneous photocatalysis and nickel catalysis.This platform utilizing cadmium sulfide semiconductor...An efficient C–P bond formation reaction was developed by virtue of the synergetic catalysis strategy by merging heterogeneous photocatalysis and nickel catalysis.This platform utilizing cadmium sulfide semiconductors as heterogeneous photocatalysts and nickel complexes as transition metal catalysts provided a variety of organophosphorus compounds from readily available aryl and vinyl halides,as well as aryl triflates,with generally a good-to-excellent reaction efficiency(31 examples,46%-98%yields).The current protocol features mild reaction conditions,a broad substrate scope,recyclability of photocatalysts,and inexpensive catalysts,thus defining the practical and economic proprieties of the present catalyst system.展开更多
Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic chemistry.Herein,we report a multi-component,regiose...Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic chemistry.Herein,we report a multi-component,regioselective bis-acylation of olefins by merging NHC organocatalysis and photoredox catalysis.With this protocol,a broad range of 1,4-diketones could be rapidly assembled using bench-stable feedstock materials.The robustness of this method was further evaluated by sensitivity screening,and good reproductivity was observed.Moreover,the diketone products could be readily converted into functionalized heterocycles,such as multi-substituted furan,pyrrole,and pyridazine.Mechanistic investigations shed light on the NHC and photoredox dual catalytic radical reaction mechanism.展开更多
Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are ob...Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.展开更多
A new 1,4-amidocyanation of 1,3-enynes with N-amidopyridin-1-ium salts and TMSCN using a copper and photoredox synergetic catalysis for producingα-amido allenyl nitriles is developed.Employing N-amidopyridin-1-ium sa...A new 1,4-amidocyanation of 1,3-enynes with N-amidopyridin-1-ium salts and TMSCN using a copper and photoredox synergetic catalysis for producingα-amido allenyl nitriles is developed.Employing N-amidopyridin-1-ium salts as the amidyl radical precursors,the reaction enables the formation of two new bonds,one C(sp^(3))-N bond and one C(sp^(2))-C(sp)bond,in a single reaction step.This reaction represents a mild,general route to the construction of theα-amido allenyl nitrile architectures,which characterizes a broad scope,a good functional group compatibility and an excellent selectivity.展开更多
A simple and efficient visible-light-induced photo redox-catalyzed diarylation of N-methacryloyl-2-arylbenzoimidazoles with aryl diazonium salts was developed.The reaction provides a conve nient access to a variety of...A simple and efficient visible-light-induced photo redox-catalyzed diarylation of N-methacryloyl-2-arylbenzoimidazoles with aryl diazonium salts was developed.The reaction provides a conve nient access to a variety of benzimidazoisoquinolinones through the construction of two C-C bonds in one step under mild reaction conditions.展开更多
In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high effic...In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.展开更多
Context and Background: Recent research has shown that the amount of energy conserved in light-matter interaction is given by the product of light’s power P times its period τ, i.e. Pτ. To date, evide...Context and Background: Recent research has shown that the amount of energy conserved in light-matter interaction is given by the product of light’s power P times its period τ, i.e. Pτ. To date, evidences of the validity of such finding are restricted to the interaction of light with capacitors, infrared spectroscopy, and vision in vertebrates. Motivation: In this article, we want to explore the validity of the role of Pτin a broader range of phenomena. Hypothesis: We assume that the photothermoelectric (PTE) effect and photoredox catalysis reactions (PCRs) are manifestations of light-matter interaction and therefore have Pτconserved in the process. Method: We take the data published in two articles, one on the PTE effect and the other on PCRs and revisit the data analysis of the authors of the original articles considering Pτas the energy conserved. Results: In the case of the PTE effect, we unveil that the size of the light’s beam cross-sectional area impinging on the photodetectors plays a major role in defining the performance of the photodetectors. With our analysis, the photodetector responsivities actually turn out to be higher than those reported in the original article. In the case of the PCRs, we find that the magnitude of Pτinvolved in successful PCRs is independent of the type of light used, whether near-infrared or blue. In addition, the involvement of Pτin the description of PCRs helps to clarify the role of the law of conservation of energy, which was neglected by the authors of the original article. Conclusions: From this study, we infer that the hypothesis that Pτthat the hypothesis that represents the amount of energy conserved in light-matter interaction is valid and general, useful to measure device performance, and predict alternative processes to achieve desired outcomes.展开更多
Solvents are known to affect the product yield in photoredox catalysis.Previously,Efforts have been made to understand how solvents affect photoredox catalysis at the ensemble level.However,the underlying mechanism ha...Solvents are known to affect the product yield in photoredox catalysis.Previously,Efforts have been made to understand how solvents affect photoredox catalysis at the ensemble level.However,the underlying mechanism has not yet been fully elucidated.Here,we studied the behavior of single photoredox catalysts in a variety of solvents by using singlemolecule fluorescence imaging.By analyzing the trajectories of single eosin Y(EY),we found that the solvent could affect photoredox catalysis both physically and chemically.Evidence of the long-lived triplet excited state of the photoredox catalyst and redox active impurities was found.These two factors may play important roles in photoredox catalysis and thus need to be given attention.展开更多
C-Glycosides,known for their superior in vivo stability compared to their O-and N-glycoside counterparts,have been widely explored as drug candidates and utilized in biological research.Traditional radical C-glycosida...C-Glycosides,known for their superior in vivo stability compared to their O-and N-glycoside counterparts,have been widely explored as drug candidates and utilized in biological research.Traditional radical C-glycosidation techniques relied on precursors such as glycosyl halides and glycosyl sulfones.These methods,however,face several challenges,including the instability of glycosyl precursors,the requirement for multi-step synthesis,and limited practicality.Herein,we present a straightforward,metal-free method to synthesize both sp^(2) and sp^(3) Cglycosides with high stereoselectivity via direct deoxy-glycosidation of readily available and stable 1-hydroxycarbohydrates.Mechanistic investigations indicate the involvement of glycosyl radicals in the reaction.Cellular assays reveal the antitumor activity of the synthesized products,which underscores the potential of this strategy in medicinal chemistry.展开更多
The bibenzyl skeleton is prevalent in numerous natural products and other biologically active compounds.Radical homocoupling provides a straightforward approach for synthesizing bibenzyls in a single step with the red...The bibenzyl skeleton is prevalent in numerous natural products and other biologically active compounds.Radical homocoupling provides a straightforward approach for synthesizing bibenzyls in a single step with the reductive homocoupling of benzyl halides undergoing extensive development.Unlike benzyl bromides and other tailored precursors used in visible-lightmediated homocoupling,benzyl chlorides offer greater abundance and chemical stability.Nevertheless,achieving chemoselective cleavage of the C-Cl bond poses significant challenges,with only a limited number of studies reported to date.Herein,we demonstrate a catalytic reductive homocoupling of benzyl chlorides facilitated by zirconocene and photoredox catalysis.This cooperative catalytic system promotes C-Cl bond cleavage in benzyl chlorides under mild conditions and supports the homocoupling of a wide range of benzyl chlorides,including those derived from pharmaceutical agents.Our preliminary mechanistic investigations highlight the pivotal role of hydrosilane in the catalytic cycle.展开更多
基金support of this work by the National Natural Science Foundation of China(Nos.22371307,21971267)the program for Guangdong Introducing Innovative and Entrepreneurial Teams(No.2017ZT07C069).
文摘Selective defluorinative functionalization of trifluoromethylarenes(ArCF3)to obtain the pharmaceutically commonα,α-difluorobenzylic motif is an attractive and elegant synthetic route.Over the past decade,although C(sp^(3))-F bonds functionalization have been greatly developed,catalytic cross-coupling of trifluoromethylarenes with C-H of terminal alkynes remains a challenge.Here,we report an approach to achieve Sonogashira-type cross-coupling of trifluoromethylarenes with terminal alkynes C(sp)-H bonds via photoredox and Cu/L dual catalysis.Tridentate anionic ligand is pivotal to realize this C-H sp-sp^(3) cross-coupling.Moreover,this unique catalytic system is also suitable for cross-coupling of C(sp^(3))-F bonds with azoles C(sp^(2))-H bonds.A series of trifluoromethylarenes,terminal alkynes and azoles with various functional groups are compatible with this protocol affording a variety of defluoroalkynylation or defluoroazolation products.Preliminary mechanistic studies indicated that deprotonated BINOL involved as a photocatalyst to activate ArCF3 rather than a ligand to the metal.
文摘Late-stage modification of complex molecules via site-selective hydrodefluorination is a challenging endeavor.The selective activation of carbon-fluorine(C-F) bonds in the presence of multiple C-F bonds is of importance in organic synthesis and drug discovery.Herein,we describe the activation of C-F bonds via multiphoton photoredox catalysis to selectively produces a series of hydrodefluorinated compounds by simply tuning the reaction conditions.Moreover,this protocol was successfully applied to the late-stage functionalization of different drug-derivatives and the corresponding mono-,di-,and tri-defluorinated products were obtained in good to excellent yields.A detailed mechanistic investigation provides insight into the unprecedented hydrodefluorination pathway.
基金Financial support from National Natural Science Foundation of China(Nos.22201202,22171206 and 22371201)Natural Science Foundation of Zhejiang Province(No.LZ23B020001)+2 种基金Open Foundation of Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers(No.E22307)Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(No.2020ZD04)Open Research Fund of Key Laboratory of the Ministry of Education for Advanced Catalysis Materials and Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces,Zhejiang Normal University。
文摘A photoredox-catalyzed synthesis ofα,α-difluoromethyl sulfones from sulfur dioxide with readily available gem–difluoroalkenes is reported.This protocol features mild reaction conditions,broad substrate scope and good functional group compatibility,giving rise to the targetα,α-difluoromethyl sulfones in moderate to excellent yields.Mechanistic studies indicate that this reaction is initiated by an aryl radical with the insertion of sulfur dioxide.
基金the National Natural Science Foundation of China(No.21901199)National Training Program of Innovation and Entrepreneurship for Undergraduates(No.S202310698011)Xi’an Jiaotong University(No.7121192002)for financial support.
文摘The radical difunctionalization of alkenes with sulfonyl bifunctional represents a powerful and straightforward approach to access functionalized alkane derivatives.However,both the mechanistic activation mode and the substrate scopes of this type of radical difunctionalizations are still limited.We demonstrate herein a modular photoredox strategy for the difunctionalization of alkenes,employing arylsulfonyl acetate as the bifunctional reagent.This approach involves a radical addition/Smiles rearrangement cascade process,offering a robust alternative for the synthesis of valuableγ,γ-diaryl andγ-aryl esters.A complementary oxidative bifunctional reagents activation mode is identified to govern the radical cascade reactions,facilitating the simultaneous incorporation of aryl and carboxylate-bearing alkyl groups into the alkenes with excellent diastereoselectivity.Noteworthy features of this method include mild reaction conditions,organophotocatalysis,high atom-and step-economy,excellent functional group compatibility and great structural diversity.
基金This work was supported by the National Natural Science Foundation of China(Nos.21872029,20903023,U1463204 and 21173045)the Program for Leading Talents of Fujian Universities,the Natural Science Foundation of Fujian Province for the Distinguished Young Investigator Rolling Grant(No.2017J07002)+1 种基金the 1st Program of Fujian Province for Top Creative Young Talents,the Natural Science Foundation of Fujian Province(No.2019J0106)the Award Program for Minjiang Scholar Professorship is gratefully acknowledged.
文摘The conversion of biomass into valuable chemicals has promise for application in biorefineries.Light-driven photoredox catalysis,with the typical features of green route and operation under mild conditions,is considered a promising strategy for renewable biomass or biomass-derived intermediates conversion into high-value-added chemical feedstocks.In this review,we strongly emphasize the recent advances in photocatalytic valorization of lignin model compounds and biomassderived alcohols.We briefl y summarize the advances in photocatalytic cleavage of theβ-O-4 bond or C–C bond into usable chemicals in the lignin model.On the other hand,we clarify not only the hybrid system for cooperative biomass-relevant alcohols oxidation and hydrogen(H2)evolution but also the tunable accessibility to variation of the target products from the same alcohol reactant by catalyst design and optimization of reaction conditions.It is hoped that this review will inspire the rational design of photoredox catalysis-based systems toward efficient biomass-derived platform molecules valorization to obtain target-oriented valuable products.
文摘Visible light‐driven carboxylation with CO_(2) have emerged as a sustainable and powerful way to transfer waste to treasure.However,it is still challenging for aryl fluorides due to the low reactivities of both C(sp2)−F bonds and CO_(2).Herein,we report the first photocatalytic carboxylation of aryl C−F bonds with CO_(2).The visible‐light photoredox catalysis enables selective carboxylation of strong C(sp2)−F bonds in diverse polyluoroarenes,such as penta‐,tetra‐,and tri‐fluoroarenes under mild conditions,providing a facile access to a series of important polyfluoroaryl carboxylic acids with good yields.In contrast to previous reports of direct capture of polyfluoroaryl radicals,mechanistic studies suggest that the reduction of fleeting polyfluoroaryl radicals into polyfluoroaryl anions might be involved in this transformation,which may open a new avenue for photocatalytic functionalization of aryl C−F bonds.
文摘The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high yields.Moreover,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.
文摘An efficient and practical route to various 3-alkoxylquinoxalin-2(1 H)-ones through visible-light photocatalytic C(sp^2)-H/O-H cross-dehydrogenation coupling of quinoxalin-2(1 H)-ones and alcohols,employing ambient air as an oxidant at room temperature under metal-free conditions,was developed.
基金supported by National Natural Science Foundation of China(No.22171133)State Key Laboratory of Analytical Chemistry for Life Science(No.5431ZZXM2308)。
文摘Glycosyl radicals,produced under mild photoredox conditions,show unique utility in the preparation of C-linked glycoconjugates.We herein report the construction of C-glycosidic bonds on α,β-dehydroalanine(DHA)of peptides with easily available glycosyl bromides as glycosyl radical precursors under highly anomeric control,leading to C-glycosylation modifications of peptides.This method not only has outstanding functional group compatibility,but also is feasible in near-physiological conditions(pH~7 and temperature T≤37℃ in aqueous media).
基金supported by the Natural Science Foundation of China (Nos. 22172030, 22072023, 21872029, U1463204 and 21173045)the Program for National Science and Technology Innovation Leading Talents (No. 00387072)+2 种基金the Program for Leading Talents of Fujian Universitiesthe 1st Program of Fujian Province for Top Creative Young Talentsthe Natural Science Foundation of Fujian Province (Nos. 2017J07002 and 2019J01631)。
文摘Ternary composites of reduced graphene oxide(GR)-CdS-Pd have been successfully synthesized via solvothermal and photodeposition methods for photocatalytic selective conversion of benzyl alcohol(BA)coupled with hydrogen(H_(2))production, which exhibit significantly improved photoactivity and selectivity than bare CdS. Mechanistic studies unveil that the cooperative effect of the close interface contact and matched energy level alignment between electrical conducting GR nanosheets(NSs) and CdS nanoparticles(NPs) in GR-CdS-Pd composite not only benefits the separation and transfer of photogenerated carriers but also improves the photocorrosion resistance of CdS. The photodeposited Pd NPs further promote the photogenerated charge separation and accelerate the formation of intermediate products(α-hydroxybenzyl radicals), thereby contributing to enhanced conversion of BA. This work would facilitate the rational design of GR as cocatalyst to construct an efficient and stable CdS-based composite photocatalyst for cooperative coupling of fine chemical synthesis and H_(2) evolution.
基金the National Science Foundation of China(21822103,21820102003,21772052,21772053,21572074,21472057)the Program of Introducing Talents of Discipline to Universities of China(111 Program,B17019)+1 种基金the Natural Science Foundation of Hubei Province(2017AHB047)the International Joint Research Center for Intelligent Biosensing Technology and Health for support of this research~~
文摘An efficient C–P bond formation reaction was developed by virtue of the synergetic catalysis strategy by merging heterogeneous photocatalysis and nickel catalysis.This platform utilizing cadmium sulfide semiconductors as heterogeneous photocatalysts and nickel complexes as transition metal catalysts provided a variety of organophosphorus compounds from readily available aryl and vinyl halides,as well as aryl triflates,with generally a good-to-excellent reaction efficiency(31 examples,46%-98%yields).The current protocol features mild reaction conditions,a broad substrate scope,recyclability of photocatalysts,and inexpensive catalysts,thus defining the practical and economic proprieties of the present catalyst system.
基金the National Natural Science Foundation of China(NSFC,Nos.22071011,21871031,22271028 and 82073998)Longquan Talents Program,the Science&Technology Department of Sichuan Province(Nos.2021YJ0404,2022JDRC0045 and 2023NSFSC1081)the innovative project of Chengdu University is gratefully acknowledged.
文摘Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic chemistry.Herein,we report a multi-component,regioselective bis-acylation of olefins by merging NHC organocatalysis and photoredox catalysis.With this protocol,a broad range of 1,4-diketones could be rapidly assembled using bench-stable feedstock materials.The robustness of this method was further evaluated by sensitivity screening,and good reproductivity was observed.Moreover,the diketone products could be readily converted into functionalized heterocycles,such as multi-substituted furan,pyrrole,and pyridazine.Mechanistic investigations shed light on the NHC and photoredox dual catalytic radical reaction mechanism.
基金the National Natural Science Foundation of China (Nos. 22225106, 22301193)Fundamental Research Funds from Sichuan University (No. 2020SCUNL102)the Fundamental Research Funds for the Central Universities。
文摘Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.
基金the National Natural Science Foundation of China(No.22271245)for the financial supportthe Yantai“Double Hundred Plan”the Talent Induction Program for Youth Innovation Teams in Colleges and Universities of Shan-dong Province。
文摘A new 1,4-amidocyanation of 1,3-enynes with N-amidopyridin-1-ium salts and TMSCN using a copper and photoredox synergetic catalysis for producingα-amido allenyl nitriles is developed.Employing N-amidopyridin-1-ium salts as the amidyl radical precursors,the reaction enables the formation of two new bonds,one C(sp^(3))-N bond and one C(sp^(2))-C(sp)bond,in a single reaction step.This reaction represents a mild,general route to the construction of theα-amido allenyl nitrile architectures,which characterizes a broad scope,a good functional group compatibility and an excellent selectivity.
基金the National Natural Science Foundation of China(No.21772062)for financial support。
文摘A simple and efficient visible-light-induced photo redox-catalyzed diarylation of N-methacryloyl-2-arylbenzoimidazoles with aryl diazonium salts was developed.The reaction provides a conve nient access to a variety of benzimidazoisoquinolinones through the construction of two C-C bonds in one step under mild reaction conditions.
基金financially supported by the Young Talents Cultivation Program of the China Association for Science and Technology(No.2015-41)The Training Programme Foundation for the Talents of the Zun Yi Science and Technology Bureau(No.201540)+1 种基金Key Programs of Guizhou Province(125 Program,No.2015039)The Natural Science Foundation of Jiangsu Province(No.BK20141265)
文摘In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.
文摘Context and Background: Recent research has shown that the amount of energy conserved in light-matter interaction is given by the product of light’s power P times its period τ, i.e. Pτ. To date, evidences of the validity of such finding are restricted to the interaction of light with capacitors, infrared spectroscopy, and vision in vertebrates. Motivation: In this article, we want to explore the validity of the role of Pτin a broader range of phenomena. Hypothesis: We assume that the photothermoelectric (PTE) effect and photoredox catalysis reactions (PCRs) are manifestations of light-matter interaction and therefore have Pτconserved in the process. Method: We take the data published in two articles, one on the PTE effect and the other on PCRs and revisit the data analysis of the authors of the original articles considering Pτas the energy conserved. Results: In the case of the PTE effect, we unveil that the size of the light’s beam cross-sectional area impinging on the photodetectors plays a major role in defining the performance of the photodetectors. With our analysis, the photodetector responsivities actually turn out to be higher than those reported in the original article. In the case of the PCRs, we find that the magnitude of Pτinvolved in successful PCRs is independent of the type of light used, whether near-infrared or blue. In addition, the involvement of Pτin the description of PCRs helps to clarify the role of the law of conservation of energy, which was neglected by the authors of the original article. Conclusions: From this study, we infer that the hypothesis that Pτthat the hypothesis that represents the amount of energy conserved in light-matter interaction is valid and general, useful to measure device performance, and predict alternative processes to achieve desired outcomes.
基金ACS Petroleum Research Fund(65009-DNI4)the University of Akron for providing funding support.
文摘Solvents are known to affect the product yield in photoredox catalysis.Previously,Efforts have been made to understand how solvents affect photoredox catalysis at the ensemble level.However,the underlying mechanism has not yet been fully elucidated.Here,we studied the behavior of single photoredox catalysts in a variety of solvents by using singlemolecule fluorescence imaging.By analyzing the trajectories of single eosin Y(EY),we found that the solvent could affect photoredox catalysis both physically and chemically.Evidence of the long-lived triplet excited state of the photoredox catalyst and redox active impurities was found.These two factors may play important roles in photoredox catalysis and thus need to be given attention.
基金supported by the National Key R&D Program of China(No.2022YFA1505100 and 2021YFA1500100)National Natural Science Foundation of China(Nos.22031008,A.L.+1 种基金212200007,W.L.)the Science Foundation of Wuhan(No.2020010601012192).
文摘C-Glycosides,known for their superior in vivo stability compared to their O-and N-glycoside counterparts,have been widely explored as drug candidates and utilized in biological research.Traditional radical C-glycosidation techniques relied on precursors such as glycosyl halides and glycosyl sulfones.These methods,however,face several challenges,including the instability of glycosyl precursors,the requirement for multi-step synthesis,and limited practicality.Herein,we present a straightforward,metal-free method to synthesize both sp^(2) and sp^(3) Cglycosides with high stereoselectivity via direct deoxy-glycosidation of readily available and stable 1-hydroxycarbohydrates.Mechanistic investigations indicate the involvement of glycosyl radicals in the reaction.Cellular assays reveal the antitumor activity of the synthesized products,which underscores the potential of this strategy in medicinal chemistry.
基金supported by JSPS KAKENHI Grant Numbers JP21H05213(Digi-TOS)(to J.Y.),JP20K15290(to E.O.),Daiichi Kigenso Kagaku Kogyo(to E.O.)Satomi Foundation(to E.O.)supported by JST ERATO Grant No.JPMJER1901(to J.Y.).
文摘The bibenzyl skeleton is prevalent in numerous natural products and other biologically active compounds.Radical homocoupling provides a straightforward approach for synthesizing bibenzyls in a single step with the reductive homocoupling of benzyl halides undergoing extensive development.Unlike benzyl bromides and other tailored precursors used in visible-lightmediated homocoupling,benzyl chlorides offer greater abundance and chemical stability.Nevertheless,achieving chemoselective cleavage of the C-Cl bond poses significant challenges,with only a limited number of studies reported to date.Herein,we demonstrate a catalytic reductive homocoupling of benzyl chlorides facilitated by zirconocene and photoredox catalysis.This cooperative catalytic system promotes C-Cl bond cleavage in benzyl chlorides under mild conditions and supports the homocoupling of a wide range of benzyl chlorides,including those derived from pharmaceutical agents.Our preliminary mechanistic investigations highlight the pivotal role of hydrosilane in the catalytic cycle.
