The authors regret<an error occurred regarding the spelling of the author’s name in the final published manuscript.The correct spelling is Jingtao Bi,but it was mistakenly published as Jingtai Bi.We hereby request...The authors regret<an error occurred regarding the spelling of the author’s name in the final published manuscript.The correct spelling is Jingtao Bi,but it was mistakenly published as Jingtai Bi.We hereby request to correct the name to Jingtao Bi as originally intended.>.The authors would like to apologize for any inconvenience caused.展开更多
The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduct...The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.展开更多
The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the ef...The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods.展开更多
Selective reduction of nitroarenes has long been a problem in organic synthesis,as a wide distribution of many different products could be generated from the multi-electron transfer processes.Development of a mild and...Selective reduction of nitroarenes has long been a problem in organic synthesis,as a wide distribution of many different products could be generated from the multi-electron transfer processes.Development of a mild and preciously controllable strong reductive catalytic system is the key challenge to realize selective reduction of nitroarenes.In this work,the authors disclose a photocatalytic strategy with formate as the electron donor via generation of the highly reductive CO_(2)radical anion species.Various arylhydroxylamines or anilines could be synthesized selectively under visible-light irradiation by simply switching the photocatalysts.Moreover,in the presence of formaldehyde,the N-methyl anilines or imidazoline derivative could also be constructed in one-pot manner.Nitroalkanes were also amendable in this photocatalytic system to selectively yield oximes.展开更多
Oxalic acid salts(oxalate)were recently developed as C1 synthon,potent single-electron-transfer(SET)reductant,and hole scavengers via generation of CO_(2) and CO_(2) radical anion(CO_(2)·^(-))under mild photochem...Oxalic acid salts(oxalate)were recently developed as C1 synthon,potent single-electron-transfer(SET)reductant,and hole scavengers via generation of CO_(2) and CO_(2) radical anion(CO_(2)·^(-))under mild photochemical conditions.A series of challenging reductive transformations were realized with oxalic dianion under catalytic photoredox conditions or through an electron-donor-acceptor(EDA)complex formation process.As a chemical intermediate for carbon capture and utilization(also a cheap and readily available reagent),oxalate salts could release one electron easily(E_(ox)=+0.06 V vs.SCE)via visible-light irradiation to give CO_(2) and CO_(2)·^(-) and therefore opened a new arena for reductive carboxylation reactions with highly expanded reaction diversity and chemical space to realize challenging C-X bond activation,alkenes cross coupling,and reductive carboxylation of unsaturated chemical bonds in a more sustainable and efficient way.This review features the recently developed aspects with oxalate salts and also an outlook for its further application in organic radical transformations.展开更多
Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on lo...Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on low-toxicity tetravalent platinum(Pt(Ⅳ))com plexes holds substantial research value.Herein,we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals(·O_(2)^(-))generation in aqueous solutions under ultrasound(US)irradiation.Given that·O_(2)^(-)is known to mediate the reduction of Pt(Ⅳ)to divalent platinum(Pt(Ⅱ)),we engineered an US-responsive dual-drug nanoprodrug(P-cisPt(Ⅳ)@5-MOP).This nanoprodrug was prepared by covalently conjugating Pt(Ⅳ)and methoxy polyethylene glycol hydroxyl(m PEG-OH)to a poly(_(L)-glutamic acid)(PLG)carrier,followed by encapsulating coumarin derivatives.Under low-intensity US irradiation(1.5 W/cm^(2),1 MHz,10 min),P-cisPt(Ⅳ)@5-MOP achieved a Pt(Ⅳ)reduction rate of 91.4%.Furthermore,upon US exposure,its half-maximal inhibitory concentration(IC_(50))against 4T1 breast cancer cells decreased dramatically from 25.7μmol/L to 0.1μmol/L.Remarkably,this system combined with US therapy yielded a tumor inhibition rate of 90.9%,with 40%of tumor-bea ring mice achieving com plete eradication of tumors,while exhibiting low systemic toxicity.Collectively,this work not only identifies a novel sonosensitizer capable of generating·O_(2)^(-)but also develops a new class of ultrasound-activatable Pt(Ⅳ)nanoprodrug.展开更多
A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The I...A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The IC50 values of these compounds range from 280 to 880 μg/mL, which should be attributed to their different substitutes.展开更多
A novel water-soluble cystine C60 derivative was synthesized in the presence of the catalyst, tetrabutylammonium hydroxide （TBAH）. The product was characterized by FT-IR, UV, ^1H NMR, ^13C NMR, MS and elemental anal...A novel water-soluble cystine C60 derivative was synthesized in the presence of the catalyst, tetrabutylammonium hydroxide （TBAH）. The product was characterized by FT-IR, UV, ^1H NMR, ^13C NMR, MS and elemental analysis. Furthermore, the scavenging ability to superoxygen anion radical O2^·- and hydroxyl radical ^·OH was studied by chemiluminescence. It was found that cystine C60 derivative showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration （IC50） for superoxygen anion radical and hydroxyl radical were 0.167 and 0.008 mg/mL, respectively.展开更多
The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates ...The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.展开更多
The data referring to the mechanism and efficiency of electronically excited macroradical and radical anionreactions, the important role of photochemical chain reactions in polymers are presented, It was found that by...The data referring to the mechanism and efficiency of electronically excited macroradical and radical anionreactions, the important role of photochemical chain reactions in polymers are presented, It was found that by varying photonenergy, temperature, photolysis time and competition between thermal and photochemical reactions, it is possible to change the functional composition and molecular weight distribution of polymers.展开更多
Water-soluble b-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2- and hydroxyl radical.OH were studied by autoxidation of pyrogallol and chemiluminescence, respectively....Water-soluble b-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2- and hydroxyl radical.OH were studied by autoxidation of pyrogallol and chemiluminescence, respectively. It was found thatβ-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.展开更多
In this study,the environmentally friendly precursor,tartaric acid(TA),was employed for the generation of CO_(2)anion radical(CO_(2)^(·-))in an advanced UV/TA/Fe^(3+)system to reduce the hazardous NO_(2)^(-)-N in...In this study,the environmentally friendly precursor,tartaric acid(TA),was employed for the generation of CO_(2)anion radical(CO_(2)^(·-))in an advanced UV/TA/Fe^(3+)system to reduce the hazardous NO_(2)^(-)-N in wastewater.To optimize this process,various factors,including the dosage of Fe^(3+),TA,and p H,were systematically investigated for their impact on the reduction process.Under the conditions of 3 mmol/L Fe^(3+)dosage,10 mmol/L TA dosage,and a pH of 2.5,NO_(2)^(-)-N was effectively removed from the water within 60 min,selectively transformed into N_(2),with a remarkable N_(2)selectivity of 91.2%.In the optimal conditions,the NO_(2)^(-)-N reduction mechanism in the UV/TA/Fe^(3+)system and the critical role of CO_(2)^(·-)were illustrated.Finally,this study explored the reduction of real nitrified seawater using the UV/TA/Fe^(3+)system.The results demonstrated that the UV/TA/Fe^(3+)system could completely eliminate NO_(2)^(-)-N and achieve a N_(2)selectivity of up to 90%,with minimal interference from coexisting ions.This work holds promising implications for the environmentally benign treatment of nitrite-polluted wastewater.展开更多
In this study, the superoxide anion radicals were generated by the auto-oxidation of 1,2,3-trihydroxybenzene and determined by UV spectrophotometry, and the reaction was found to be facilitated by anthraquinone-2-sulf...In this study, the superoxide anion radicals were generated by the auto-oxidation of 1,2,3-trihydroxybenzene and determined by UV spectrophotometry, and the reaction was found to be facilitated by anthraquinone-2-sulfonic acid sodium salt. The bamboo kraft pulps were treated by the 1,2,3-trihydroxybenzene auto-oxidation method or the 1,2,3-trihydroxybenzene auto-oxidation combined with anthraquinone-2-sulfonic acid sodium salt to show the ef-fect of the superoxide anion radicals during the oxygen delignification of bamboo kraft pulp and the enhancing af-fect of anthraquinone compounds as an additive on delignification. The results indicated that the superoxide anion radicals could react with lignin and remove it from pulp with negligible damage on cellulose, and the an-thraquinone-2-sulfonic acid sodium salt could facilitate the generation of superoxide anion radical to enhance delig-nification of pulps. The oxygen delignification selectivity could be improved using the 1,2,3-trihydroxybenzene auto-oxidation system combined with anthraquinone-2-sulfonic acid sodium salt.展开更多
UAtomic oxygen radical anion （O-） is one of the most active oxygen species, and has extremely high oxidation ability toward small-molecules of hydrocarbons. However, to our knowledge, little is known about the effec...UAtomic oxygen radical anion （O-） is one of the most active oxygen species, and has extremely high oxidation ability toward small-molecules of hydrocarbons. However, to our knowledge, little is known about the effects of O- on cells of micro-organisms. This work showed that O- could quickly react with the Bacillus subtilis cells and seriously damage the cell walls a s well as their other contents, leading to a fast and irreversible inactivation. SEM micrographs revealed that the cell structures were dramatically destroyed by their exposure to O-. The inactivation efficiencies of B. subtilis depend on the O- intensity, the initial population of cells and the treatment temperature, but not on the pH in the range of our investigation. For a cell concentration of 10^6 cfu/ml, the number of survived cells dropped from 10^6 cfu/ml to 10^3 cfu/ml after about five-minute irradiation by an O- flux in an intensity of 233 nA/cm^2 under a dry argon environment （30 ℃, 1 atm, exposed size： 1.8 cm^2）. The inactivation mechanism of micro-organisms induced by O- is also discussed.展开更多
Despite the extensive application of advanced oxidation processes(AOPs)in water treatment,the efficiency of AOPs in eliminating various emerging contaminants such as halogenated antibiotics is constrained by a number ...Despite the extensive application of advanced oxidation processes(AOPs)in water treatment,the efficiency of AOPs in eliminating various emerging contaminants such as halogenated antibiotics is constrained by a number of factors.Halogen moieties exhibit strong resistance to oxidative radicals,affecting the dehalogenation and detoxification efficiencies.To address these limitations of AOPs,advanced reduction processes(ARPs)have been proposed.Herein,a novel nucleophilic reductant—namely,the carbon dioxide radical anion(CO_(2)^(·-))—is introduced for the simultaneous degradation,dehalogenation,and detoxification of florfenicol(FF),a typical halogenated antibiotic.The results demonstrate that FF is completely eliminated by CO_(2)^(·-),with approximately 100%of Cland 46%of Freleased after 120 min of treatment.Simultaneous detoxification is observed,which exhibits a linear response to the release of free inorganic halogen ions(R^(2)=0.97,p<0.01).The formation of halogen-free products is the primary reason for the superior detoxification performance of this method,in comparison with conventional hydroxyl-radical-based AOPs.Products identification and density functional theory(DFT)calculations reveal the underlying dehalogenation mechanism,in which the chlorine moiety of FF is more susceptible than other moieties to nucleophilic attack by CO_(2)^(·-).Moreover,CO_(2)^(·-)-based ARPs exhibit superior dehalogenation efficiencies(>75%)in degrading a series of halogenated antibiotics,including chloramphenicol(CAP),thiamphenicol(THA),diclofenac(DLF),triclosan(TCS),and ciprofloxacin(CIP).The system shows high tolerance to the pH of the solution and the presence of natural water constituents,and demonstrates an excellent degradation performance in actual groundwater,indicating the strong application potential of CO_(2)^(·-)-based ARPs in real life.Overall,this study elucidates the feasibility of CO_(2)^(·-)for the simultaneous degradation,dehalogenation,and detoxification of halogenated antibiotics and provides a promising method for their regulation during water or wastewater treatment.展开更多
Photoinduced molecular oxygen activation is crucial for artificial photosynthesis.However,metal-free semiconductor photocatalysts with high activation efficiency are still lacking up to now.Herein,two isomorphic tris(...Photoinduced molecular oxygen activation is crucial for artificial photosynthesis.However,metal-free semiconductor photocatalysts with high activation efficiency are still lacking up to now.Herein,two isomorphic tris(triazolo)triazine-based covalent organic frameworks were successfully constructed under solvothermal conditions.And they possess high crystallinity,inherent porosity with large surface area and good stability.Strong electron donor-acceptor skeletons expand the visible light harvesting,also facilitate the charge separation and thus lead to their superior activity of photoinduced molecular oxygen activation including photosynthesis of tetrahydroquinolines and hydrogen peroxide.This work provides a way to improve the efficiency of molecular oxygen activation through the rational design of COFs,and also opens new avenues for the construction of highly active and metal-free photocatalysts toward sustainable solar-to-chemical energy conversion.展开更多
It is important to search for the ingredients with SOD—like activity present in Chinese traditional drugs.Four classes of constituents including fifteen compounds isolated from Chinese rhubarb were studied for their ...It is important to search for the ingredients with SOD—like activity present in Chinese traditional drugs.Four classes of constituents including fifteen compounds isolated from Chinese rhubarb were studied for their SOD-like activity by determining the percentage of scavenging effect of the superoxide radical anion (O2),(S％),The results showed that the SOD-like activities of four tanninoid compounds were stronger among which(—)-epi- catechin has the strongest SOD-like activity at lower concentrations:the activity of five stil- bene compounds is weaker:while chrysophanol-8-glucoside and desoxyrhaponticin have no SOD-like activity and,on the contrary.may promote the production of O_2^-展开更多
The potential energy profile of the reaction between the atomic oxygen radical anion and acetonitrile has been mapped at the G3MP2B3 level of theory. Geometries of the reactants, products, intermediate complexes, and ...The potential energy profile of the reaction between the atomic oxygen radical anion and acetonitrile has been mapped at the G3MP2B3 level of theory. Geometries of the reactants, products, intermediate complexes, and transition states involved in this reaction have been optimized at the （U）B3LYP/6-31＋G（d,p） level, and then their accurate relative energies have been improved using the G3MP2B3 method. The potential energy profile is confirmed via intrinsic reaction coordinate calculations of transition states. Four possible production channels are examined respectively, as H＋ transfer, H-atom transfer, H2＋ transfer, and bi- molecular nucleophilic substitution （SN2） reaction pathways. Based on present calculations, the H2＋ transfer reaction is major among these four channels, which agrees with previous experimental conclusions.展开更多
Achieving multilevel conduction in a cost-effective transition metal complex of a redox-active ligand will be an efficient way for designing a molecular memristor.This study presents a rare example of a tris-azo anion...Achieving multilevel conduction in a cost-effective transition metal complex of a redox-active ligand will be an efficient way for designing a molecular memristor.This study presents a rare example of a tris-azo anion radical ligand-wrapped singlet five-coordinate low-spin Co(Ⅱ)complex,[(L)^(·−)Co(Ⅱ)]PF_(6),[1]PF_(6),that showed solution-processible resistive switching memory with synaptic functionality.The single-crystal X-ray structure,variable-temperature magnetic studies,and DFT calculations of[1]PF_(6) showed that it has a one-electron-reduced ligand,[L]^(·−),which is antiferromagnetically coupled with the low-spin Co(Ⅱ)center that results in an s=0 ground state.[1]PF_(6) showed multiple reversible and quasi-reversible redox events,indicating that it can be explored as a molecular memristor.The indium tin oxide/[1]PF_(6)/Ag memristor demonstrated excellent switching performance with a large ON/OFF ratio(>10^(3)),excellent endurance(>500 cycles),long retention time(>10^(4) s),and long-term stability at an elevated temperature(100℃).Moreover,upon applying pulsed electrical stimuli,the memristor exhibited potentiation and depression behaviors,a key feature for synaptic plasticity.The device was SET at a cathodic potential,and thus,the facile ligand-based reductions in[1]PF_(6) played a decisive role in the device.展开更多
Persistent radical-containing hybrid materials are a focus of attention due to their functions such as photomodulated electrical conductivity,magnetism,and photochromism.Such hybrid materials are relatively underexplo...Persistent radical-containing hybrid materials are a focus of attention due to their functions such as photomodulated electrical conductivity,magnetism,and photochromism.Such hybrid materials are relatively underexplored,however,mainly due to the lack of suitable highly photoactive building blocks.In this work,a hybrid material SiMo-NDI with persistent radical anions was rationally designed and prepared by incorporating photoactive naphthalenediimides(NDIs)and polyoxometallate into its structure.Characterization of SiMo-NDI not only confirmed its photochromism and narrow band gap,but also revealed the radical derived from photoinduced electron transfer between the NDI and electron donor.The persistent radical and strong near-infrared absorption characteristics of this hybrid material enable effective near-infrared photothermal conversion.Moreover,it can efficiently generate superoxide radical anions under light irradiation which promote the photocatalytic hydroxylation of arylboronic acids and C-3 thiocyanation of indoles in high yield with good recyclability at room temperature and without additives.展开更多
文摘The authors regret<an error occurred regarding the spelling of the author’s name in the final published manuscript.The correct spelling is Jingtao Bi,but it was mistakenly published as Jingtai Bi.We hereby request to correct the name to Jingtao Bi as originally intended.>.The authors would like to apologize for any inconvenience caused.
基金funding programs,the Walter Benjamin Programme(DFG,German Research Foundation,project number:530742479)the ProChancecareer Programme for the Promotion of Equal Opportunities in Academia for providing the financial support+1 种基金financial support by the Deutsche Forschungsgemeinschaft via the TRR 234 Cata Light(DFG,German Research Foundation)-Projektnummer 364549901-TRR 234[B6]the financial support taken from the CSIR and UGC,Delhi,India。
文摘The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.
基金supported by the National Natural Science Foundation of China(Nos.52270165 and 51978537)the Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province。
文摘The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods.
基金financially supported by the Jiangsu Province Shuangchuang Ph.D Award(No.JSSCBS20211267,Pei Xu)the Natural Science Research Project of Jiangsu Universities(No.23KJB150037,Pei Xu)+1 种基金sponsored by the Jiangsu Specially-Appointed Professor program(Xu Zhu)the start-up funding provided by Xuzhou Medical University。
文摘Selective reduction of nitroarenes has long been a problem in organic synthesis,as a wide distribution of many different products could be generated from the multi-electron transfer processes.Development of a mild and preciously controllable strong reductive catalytic system is the key challenge to realize selective reduction of nitroarenes.In this work,the authors disclose a photocatalytic strategy with formate as the electron donor via generation of the highly reductive CO_(2)radical anion species.Various arylhydroxylamines or anilines could be synthesized selectively under visible-light irradiation by simply switching the photocatalysts.Moreover,in the presence of formaldehyde,the N-methyl anilines or imidazoline derivative could also be constructed in one-pot manner.Nitroalkanes were also amendable in this photocatalytic system to selectively yield oximes.
基金financially supported by the Jiangsu Province Shuangchuang Ph.D.award(No.JSSCBS20211267,Pei Xu)the Natural Science Research Project of Jiangsu Universities(No.23KJB150037,Pei Xu)+2 种基金sponsored by the Jiangsu Specially-Appointed Professor Program(Xu Zhu)the Start-up Funding provided by Xuzhou Medical UniversityThe Public Experimental Research Center of Xuzhou Medical University is also acknowledged。
文摘Oxalic acid salts(oxalate)were recently developed as C1 synthon,potent single-electron-transfer(SET)reductant,and hole scavengers via generation of CO_(2) and CO_(2) radical anion(CO_(2)·^(-))under mild photochemical conditions.A series of challenging reductive transformations were realized with oxalic dianion under catalytic photoredox conditions or through an electron-donor-acceptor(EDA)complex formation process.As a chemical intermediate for carbon capture and utilization(also a cheap and readily available reagent),oxalate salts could release one electron easily(E_(ox)=+0.06 V vs.SCE)via visible-light irradiation to give CO_(2) and CO_(2)·^(-) and therefore opened a new arena for reductive carboxylation reactions with highly expanded reaction diversity and chemical space to realize challenging C-X bond activation,alkenes cross coupling,and reductive carboxylation of unsaturated chemical bonds in a more sustainable and efficient way.This review features the recently developed aspects with oxalate salts and also an outlook for its further application in organic radical transformations.
基金financially supported by the National Natural Science Foundation of China(Nos.52533015,52495013,52403211,52573183,52273157,52073279 and 52025035)Jilin Province,China(Nos.20250601009RC and 20230508102RC)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2022224)。
文摘Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on low-toxicity tetravalent platinum(Pt(Ⅳ))com plexes holds substantial research value.Herein,we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals(·O_(2)^(-))generation in aqueous solutions under ultrasound(US)irradiation.Given that·O_(2)^(-)is known to mediate the reduction of Pt(Ⅳ)to divalent platinum(Pt(Ⅱ)),we engineered an US-responsive dual-drug nanoprodrug(P-cisPt(Ⅳ)@5-MOP).This nanoprodrug was prepared by covalently conjugating Pt(Ⅳ)and methoxy polyethylene glycol hydroxyl(m PEG-OH)to a poly(_(L)-glutamic acid)(PLG)carrier,followed by encapsulating coumarin derivatives.Under low-intensity US irradiation(1.5 W/cm^(2),1 MHz,10 min),P-cisPt(Ⅳ)@5-MOP achieved a Pt(Ⅳ)reduction rate of 91.4%.Furthermore,upon US exposure,its half-maximal inhibitory concentration(IC_(50))against 4T1 breast cancer cells decreased dramatically from 25.7μmol/L to 0.1μmol/L.Remarkably,this system combined with US therapy yielded a tumor inhibition rate of 90.9%,with 40%of tumor-bea ring mice achieving com plete eradication of tumors,while exhibiting low systemic toxicity.Collectively,this work not only identifies a novel sonosensitizer capable of generating·O_(2)^(-)but also develops a new class of ultrasound-activatable Pt(Ⅳ)nanoprodrug.
文摘A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The IC50 values of these compounds range from 280 to 880 μg/mL, which should be attributed to their different substitutes.
基金The project supported by the National Natural Science Foundation of China(No.20474020).
文摘A novel water-soluble cystine C60 derivative was synthesized in the presence of the catalyst, tetrabutylammonium hydroxide （TBAH）. The product was characterized by FT-IR, UV, ^1H NMR, ^13C NMR, MS and elemental analysis. Furthermore, the scavenging ability to superoxygen anion radical O2^·- and hydroxyl radical ^·OH was studied by chemiluminescence. It was found that cystine C60 derivative showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration （IC50） for superoxygen anion radical and hydroxyl radical were 0.167 and 0.008 mg/mL, respectively.
文摘The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.
基金This work was financially supported by Federal program "Integration" (Grant A0114).
文摘The data referring to the mechanism and efficiency of electronically excited macroradical and radical anionreactions, the important role of photochemical chain reactions in polymers are presented, It was found that by varying photonenergy, temperature, photolysis time and competition between thermal and photochemical reactions, it is possible to change the functional composition and molecular weight distribution of polymers.
文摘Water-soluble b-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2- and hydroxyl radical.OH were studied by autoxidation of pyrogallol and chemiluminescence, respectively. It was found thatβ-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.
基金financially supported by National Natural Science Foundation of China(No.22208081)Central Guidance on Local Science and Technology Development Fund of Hebei Province(No.226Z3102G)Fundamental Research Funds of Hebei University of Technology(No.JBKYTD2001)。
文摘In this study,the environmentally friendly precursor,tartaric acid(TA),was employed for the generation of CO_(2)anion radical(CO_(2)^(·-))in an advanced UV/TA/Fe^(3+)system to reduce the hazardous NO_(2)^(-)-N in wastewater.To optimize this process,various factors,including the dosage of Fe^(3+),TA,and p H,were systematically investigated for their impact on the reduction process.Under the conditions of 3 mmol/L Fe^(3+)dosage,10 mmol/L TA dosage,and a pH of 2.5,NO_(2)^(-)-N was effectively removed from the water within 60 min,selectively transformed into N_(2),with a remarkable N_(2)selectivity of 91.2%.In the optimal conditions,the NO_(2)^(-)-N reduction mechanism in the UV/TA/Fe^(3+)system and the critical role of CO_(2)^(·-)were illustrated.Finally,this study explored the reduction of real nitrified seawater using the UV/TA/Fe^(3+)system.The results demonstrated that the UV/TA/Fe^(3+)system could completely eliminate NO_(2)^(-)-N and achieve a N_(2)selectivity of up to 90%,with minimal interference from coexisting ions.This work holds promising implications for the environmentally benign treatment of nitrite-polluted wastewater.
基金Supported by the National Natural Science Foundation of China (No.20477046)the Natural Science Foundation of Fujian Prov-ince of China (No.2004HZ03-5)the Young Scientist Innovation Foundation of Fujian Province of China (No.2006F3009).
文摘In this study, the superoxide anion radicals were generated by the auto-oxidation of 1,2,3-trihydroxybenzene and determined by UV spectrophotometry, and the reaction was found to be facilitated by anthraquinone-2-sulfonic acid sodium salt. The bamboo kraft pulps were treated by the 1,2,3-trihydroxybenzene auto-oxidation method or the 1,2,3-trihydroxybenzene auto-oxidation combined with anthraquinone-2-sulfonic acid sodium salt to show the ef-fect of the superoxide anion radicals during the oxygen delignification of bamboo kraft pulp and the enhancing af-fect of anthraquinone compounds as an additive on delignification. The results indicated that the superoxide anion radicals could react with lignin and remove it from pulp with negligible damage on cellulose, and the an-thraquinone-2-sulfonic acid sodium salt could facilitate the generation of superoxide anion radical to enhance delig-nification of pulps. The oxygen delignification selectivity could be improved using the 1,2,3-trihydroxybenzene auto-oxidation system combined with anthraquinone-2-sulfonic acid sodium salt.
基金the innovation program 2002 by CAS in China,(No.KJ0364)
文摘UAtomic oxygen radical anion （O-） is one of the most active oxygen species, and has extremely high oxidation ability toward small-molecules of hydrocarbons. However, to our knowledge, little is known about the effects of O- on cells of micro-organisms. This work showed that O- could quickly react with the Bacillus subtilis cells and seriously damage the cell walls a s well as their other contents, leading to a fast and irreversible inactivation. SEM micrographs revealed that the cell structures were dramatically destroyed by their exposure to O-. The inactivation efficiencies of B. subtilis depend on the O- intensity, the initial population of cells and the treatment temperature, but not on the pH in the range of our investigation. For a cell concentration of 10^6 cfu/ml, the number of survived cells dropped from 10^6 cfu/ml to 10^3 cfu/ml after about five-minute irradiation by an O- flux in an intensity of 233 nA/cm^2 under a dry argon environment （30 ℃, 1 atm, exposed size： 1.8 cm^2）. The inactivation mechanism of micro-organisms induced by O- is also discussed.
基金financially supported by the National Natural Science Foundation of China(22176059,21777042,and 22076045)the authors would also like to acknowledge support from the Science and Technology Commission of Shanghai Municipality’s Yangfan Special Project(23YF1408400)the Fundamental Research Funds for the Central Universities.
文摘Despite the extensive application of advanced oxidation processes(AOPs)in water treatment,the efficiency of AOPs in eliminating various emerging contaminants such as halogenated antibiotics is constrained by a number of factors.Halogen moieties exhibit strong resistance to oxidative radicals,affecting the dehalogenation and detoxification efficiencies.To address these limitations of AOPs,advanced reduction processes(ARPs)have been proposed.Herein,a novel nucleophilic reductant—namely,the carbon dioxide radical anion(CO_(2)^(·-))—is introduced for the simultaneous degradation,dehalogenation,and detoxification of florfenicol(FF),a typical halogenated antibiotic.The results demonstrate that FF is completely eliminated by CO_(2)^(·-),with approximately 100%of Cland 46%of Freleased after 120 min of treatment.Simultaneous detoxification is observed,which exhibits a linear response to the release of free inorganic halogen ions(R^(2)=0.97,p<0.01).The formation of halogen-free products is the primary reason for the superior detoxification performance of this method,in comparison with conventional hydroxyl-radical-based AOPs.Products identification and density functional theory(DFT)calculations reveal the underlying dehalogenation mechanism,in which the chlorine moiety of FF is more susceptible than other moieties to nucleophilic attack by CO_(2)^(·-).Moreover,CO_(2)^(·-)-based ARPs exhibit superior dehalogenation efficiencies(>75%)in degrading a series of halogenated antibiotics,including chloramphenicol(CAP),thiamphenicol(THA),diclofenac(DLF),triclosan(TCS),and ciprofloxacin(CIP).The system shows high tolerance to the pH of the solution and the presence of natural water constituents,and demonstrates an excellent degradation performance in actual groundwater,indicating the strong application potential of CO_(2)^(·-)-based ARPs in real life.Overall,this study elucidates the feasibility of CO_(2)^(·-)for the simultaneous degradation,dehalogenation,and detoxification of halogenated antibiotics and provides a promising method for their regulation during water or wastewater treatment.
文摘Photoinduced molecular oxygen activation is crucial for artificial photosynthesis.However,metal-free semiconductor photocatalysts with high activation efficiency are still lacking up to now.Herein,two isomorphic tris(triazolo)triazine-based covalent organic frameworks were successfully constructed under solvothermal conditions.And they possess high crystallinity,inherent porosity with large surface area and good stability.Strong electron donor-acceptor skeletons expand the visible light harvesting,also facilitate the charge separation and thus lead to their superior activity of photoinduced molecular oxygen activation including photosynthesis of tetrahydroquinolines and hydrogen peroxide.This work provides a way to improve the efficiency of molecular oxygen activation through the rational design of COFs,and also opens new avenues for the construction of highly active and metal-free photocatalysts toward sustainable solar-to-chemical energy conversion.
基金This project was supported by the National Natural Science Foundation of ChinaA preliminary report of this work has heen presented at the First International Symposium OH Rhubarb.Chengde China.May 30.1990
文摘It is important to search for the ingredients with SOD—like activity present in Chinese traditional drugs.Four classes of constituents including fifteen compounds isolated from Chinese rhubarb were studied for their SOD-like activity by determining the percentage of scavenging effect of the superoxide radical anion (O2),(S％),The results showed that the SOD-like activities of four tanninoid compounds were stronger among which(—)-epi- catechin has the strongest SOD-like activity at lower concentrations:the activity of five stil- bene compounds is weaker:while chrysophanol-8-glucoside and desoxyrhaponticin have no SOD-like activity and,on the contrary.may promote the production of O_2^-
文摘The potential energy profile of the reaction between the atomic oxygen radical anion and acetonitrile has been mapped at the G3MP2B3 level of theory. Geometries of the reactants, products, intermediate complexes, and transition states involved in this reaction have been optimized at the （U）B3LYP/6-31＋G（d,p） level, and then their accurate relative energies have been improved using the G3MP2B3 method. The potential energy profile is confirmed via intrinsic reaction coordinate calculations of transition states. Four possible production channels are examined respectively, as H＋ transfer, H-atom transfer, H2＋ transfer, and bi- molecular nucleophilic substitution （SN2） reaction pathways. Based on present calculations, the H2＋ transfer reaction is major among these four channels, which agrees with previous experimental conclusions.
基金the Science&Engineering Research Board(Grant No.CRG/2023/001476)Government of India,for the financial support+6 种基金IIT Jammu for providing seed grant supportUGC and HTRA(MHRD,IIT Jammu)for the fellowship supportthe Council of Scientific and Industrial Research,Govt.of India,for the financial assistanceAnusandhan National Research Foundation(ANRF),Government of India(Grant No.CRG/2022/006352formerly Science&Engineering Research Board),for the financial supportthe Department of Atomic Energy(DAE),Government of India,for the financial support(Grant No.0803/2/2020/NISER/R&D-II/8149)the High-Performance Computing Facility AGASTYA of IIT Jammu.
文摘Achieving multilevel conduction in a cost-effective transition metal complex of a redox-active ligand will be an efficient way for designing a molecular memristor.This study presents a rare example of a tris-azo anion radical ligand-wrapped singlet five-coordinate low-spin Co(Ⅱ)complex,[(L)^(·−)Co(Ⅱ)]PF_(6),[1]PF_(6),that showed solution-processible resistive switching memory with synaptic functionality.The single-crystal X-ray structure,variable-temperature magnetic studies,and DFT calculations of[1]PF_(6) showed that it has a one-electron-reduced ligand,[L]^(·−),which is antiferromagnetically coupled with the low-spin Co(Ⅱ)center that results in an s=0 ground state.[1]PF_(6) showed multiple reversible and quasi-reversible redox events,indicating that it can be explored as a molecular memristor.The indium tin oxide/[1]PF_(6)/Ag memristor demonstrated excellent switching performance with a large ON/OFF ratio(>10^(3)),excellent endurance(>500 cycles),long retention time(>10^(4) s),and long-term stability at an elevated temperature(100℃).Moreover,upon applying pulsed electrical stimuli,the memristor exhibited potentiation and depression behaviors,a key feature for synaptic plasticity.The device was SET at a cathodic potential,and thus,the facile ligand-based reductions in[1]PF_(6) played a decisive role in the device.
基金supported by the National Natural Science Foundation of China(22269018 and 21961030)Basis Research Joint Project of Yunnan Local Colleges(202301BA070001-101)Key Laboratory of Yunnan Provincial Department of Education,Scientific and Technological Innovation Team for Function-Oriented Crystalline Porous Materials in Yunnan Institutions of Higher Learning,and Program for Innovative Research Team in Qujing Normal University.
文摘Persistent radical-containing hybrid materials are a focus of attention due to their functions such as photomodulated electrical conductivity,magnetism,and photochromism.Such hybrid materials are relatively underexplored,however,mainly due to the lack of suitable highly photoactive building blocks.In this work,a hybrid material SiMo-NDI with persistent radical anions was rationally designed and prepared by incorporating photoactive naphthalenediimides(NDIs)and polyoxometallate into its structure.Characterization of SiMo-NDI not only confirmed its photochromism and narrow band gap,but also revealed the radical derived from photoinduced electron transfer between the NDI and electron donor.The persistent radical and strong near-infrared absorption characteristics of this hybrid material enable effective near-infrared photothermal conversion.Moreover,it can efficiently generate superoxide radical anions under light irradiation which promote the photocatalytic hydroxylation of arylboronic acids and C-3 thiocyanation of indoles in high yield with good recyclability at room temperature and without additives.
