The ZnO-Ag core-shell nanoparticle in ethanol was prepared by photoreduction and colloidal methods. The experimental results obtained from the absorption spectrum, fluorescence spectrum and electron microscopy reveale...The ZnO-Ag core-shell nanoparticle in ethanol was prepared by photoreduction and colloidal methods. The experimental results obtained from the absorption spectrum, fluorescence spectrum and electron microscopy revealed that the structure of the hybrid particle is ZnO core covered with Ag. The thickness of silver layer formed on ZnO core can be controlled by the concentration of Ag+ and the time of UV irradiation.In addition, the electrical properties of the charge double layer of the ZnO particle greatly affect the formation of ZnO-Ag hybrid particle.展开更多
The ability to selectively introduce diverse functionality onto hydrocarbons is of substantial value in the synthesis of both small molecules and pharmaceuticals.In this endeavour,as a photocatalyst-and metalfree proc...The ability to selectively introduce diverse functionality onto hydrocarbons is of substantial value in the synthesis of both small molecules and pharmaceuticals.In this endeavour,as a photocatalyst-and metalfree process,the electron donor–acceptor(EDA)strategy has not been well explored.Here we report an approach to aliphatic carbon-hydrogen bond diversification through an EDA complex constituted by HCl and S^(IV)=O groups.As an efficient hydrogen atom transfer(HAT)reagent,chlorine radical can be produced via a proton-coupled electron transfer process in this system.Based on this unusual path,a photopromoted versatile aliphatic C–H functionalization is developed without photo-and metal-catalysts,including thiolation,arylation,alkynylation,and allylation.This conversion has concise and ambient reaction conditions,good functional group tolerance,and substrate diversity,and provides an alternative solution for the high value-added utilization of bulk light alkanes.展开更多
Bifunctional reagents that serve as dual coupling partners with an activating species have emerged as valuable synthetic tools in organic chemistry.They allow for the development of diverse reaction modes with enhance...Bifunctional reagents that serve as dual coupling partners with an activating species have emerged as valuable synthetic tools in organic chemistry.They allow for the development of diverse reaction modes with enhanced efficiency and structural variability,which is in high demand for atom-economic and sustainable synthesis.Among them,bifunctional reagents containing Nheteroaryl groups have received much attention due to their ability to introduce privileged N-heteroaryl moieties into complex molecules that are otherwise challenging to access.Furthermore,these reagents have been employed under visible-light conditions to achieve various synthetic applications,enabling difunctionalization of alkenes,alkynes,and[1.1.1]propellanes under mild reaction conditions,providing access to highly functionalized N-heteroarenes.In this review,we provide an overview of the recent achievements and applications of photoinduced difunctionalization using bifunctional reagents containing N-heteroaryl groups.We systematically categorize the representative contributions in the field based on bifunctional reagents and their reactivity patterns.This review aims to highlight the potential of these reagents as powerful synthetic tools for sustainable and diverse synthesis.展开更多
Photodynamic therapy(PDT)usually shows limited efficacy in solid tumors since traditional PDT is O_(2)^(-)dependent while solid tumors are inherently hypoxic.In addition,hypoxic tumor cells possess antiapoptotic pathw...Photodynamic therapy(PDT)usually shows limited efficacy in solid tumors since traditional PDT is O_(2)^(-)dependent while solid tumors are inherently hypoxic.In addition,hypoxic tumor cells possess antiapoptotic pathways that resist PDT-induced apoptosis.Therefore,developing photosensitizers(PSs)that show low O_(2)^(-)dependency and can induce nonapoptotic cell death pathways is critically needed.Herein,a series of Ru(II)polypyridine complex-based PSs,RuNMe,RuH,and RuCN,were synthesized,and their applications against hypoxic tumor cells through PDT were investigated.All three complexes showthe ability to generate the superoxide anion radical(·O_(2)^(-)),which is the type I photoreaction and less O_(2)^(-)dependent.RuNMe shows the best PDT performance against MCF-7 cells and three-dimensional multicellular spheroids,due to its higher cellular uptake and more reactive oxygen species generation.More importantly,RuNMe-incubated MCF-7 cells show photoinduced ferroptosis as evidenced by glutathione peroxidase 4 downregulation and lipid peroxide accumulation.This work not only develops a novel ferroptosis-inducing Ru(II)complex with the type I PDT process but also offers an effective strategy to solve tumor hypoxia in PDT.展开更多
Photochromic diarylethenes have been widely used in many fields. However, their cyclization process must be induced by UV light. In this article, a simple strategy is developed by extending π-conjugation with electro...Photochromic diarylethenes have been widely used in many fields. However, their cyclization process must be induced by UV light. In this article, a simple strategy is developed by extending π-conjugation with electron donating groups. The modified dirylethene derivative can photocyclolize under 405-nm light with a good photochromic efficiency. Meanwhile, its absorption and moderate fluorescence can be switched effectively in both directions by visible lights(405 and 520 nm, respectively) in different solutions and in living cells. We believe that this simple method will become a versatile strategy for developing various dirylethylenes with visible-light photochromism.展开更多
The first example of the p-orbital overlap controlled enantioselectivity of Norrish type II photocyclization reaction was described. Irradiation of 5-methyl bicyclo[l. 1.1 ]pentanyl ketone with UV in the solid state a...The first example of the p-orbital overlap controlled enantioselectivity of Norrish type II photocyclization reaction was described. Irradiation of 5-methyl bicyclo[l. 1.1 ]pentanyl ketone with UV in the solid state as well as in the acetonitrile solution afforded the Norrish/Yang photocyclization compound as the sole product. Solid-state asymmetric photochemical studies using ionic chiral auxiliary technique led to the enantioselectivity as high as 60%. The results were rationalized by Xray single crystal structure.展开更多
Organic matters in drinking water of Kaschin-Beck disease areas were extracted. Then analyses and characterization were performed by means of multiply chemical and physical methods. The results did not show the obviou...Organic matters in drinking water of Kaschin-Beck disease areas were extracted. Then analyses and characterization were performed by means of multiply chemical and physical methods. The results did not show the obvious difference in the frame structure of humic substances and the structure of rmcromolecular compounds in the drinking water of disease and non-disease areas, but the difference in the contents of some micromolecular compounds and radicals. The investigation also includes the preliminary research on the photoreaction of drinking water from disease and non-disease areas and the accumulation of natural organic matter in the bone of tested animals.展开更多
An X-band EPR study on a Na_3(CrMo_6O_(24)H_6)·8H_2O single crystal diluted by its isomor-phic compound Na_3(AlMo_6O_(24)H_6)·8H_2O at room temperature is reported. Using the least squares-fitting method to ...An X-band EPR study on a Na_3(CrMo_6O_(24)H_6)·8H_2O single crystal diluted by its isomor-phic compound Na_3(AlMo_6O_(24)H_6)·8H_2O at room temperature is reported. Using the least squares-fitting method to simulate the EPR data for principal planes, the Hamiltonian parameterswere obtained. The principal values of the g tensors are g_(ZZ) = 1.904, g_(XX)= 1.973, g_(YY)=1.933. The zero field splitting tensor parameters are D = 0.275 cm^(-1), E = 0.05 cm^(-1). The fielddependence of Cr^(3+) energy levels with field at different angles from the principal axes whenthe field is along the principal planes is calculated based on these experimental parameters.The isofrequency plots of calculated field vs. angle are also shown. They agree well with theexperimental results.展开更多
Molecular design, synthesis and photochromic properties of spirooxazines and fulgides are described. In the case of fulgides, the change of the substituents may lead to different photochromic properties and different ...Molecular design, synthesis and photochromic properties of spirooxazines and fulgides are described. In the case of fulgides, the change of the substituents may lead to different photochromic properties and different photoreactions of the kind of compounds. In photochromic process of pyrryl-substituted fulgides, the excited singlet state is the mam species, but the excited triplet state is also involved. However, no excited triplet state has been observed in cyclization of aryl-substituted fulgides. In the case of spirooxazines, the substituents at 2’-position have great effect on the formation of photoproduct and on the mechanism of photoreaction. The increase of steric hindrance of the 2’-position substituent gives rise to the decrease of the quantum yield for the formation of photochromic merocyanine (PMC) and the increase of the relative quantum yield for the charge separated twist intermediate (CT).展开更多
文摘The ZnO-Ag core-shell nanoparticle in ethanol was prepared by photoreduction and colloidal methods. The experimental results obtained from the absorption spectrum, fluorescence spectrum and electron microscopy revealed that the structure of the hybrid particle is ZnO core covered with Ag. The thickness of silver layer formed on ZnO core can be controlled by the concentration of Ag+ and the time of UV irradiation.In addition, the electrical properties of the charge double layer of the ZnO particle greatly affect the formation of ZnO-Ag hybrid particle.
基金supported by the National Key Research and Development Program of China(2022YFC2804105)the Joint Fund of Shandong Natural Science Foundation(ZR2021LSW013)+5 种基金Natural Science Foundation of Shandong Province(ZR2020QB044,ZR2020QH364,ZR2023MH245,and ZR2022QB090)Postdoctoral Science Foundation of China(2020M682157)Qingdao Emerging Industry Cultivation Project in 2023(23-1-4-xxgg-19-nsh)Shandong Provincial Science and Technology SME Innovation Capacity Improvement Project(2022TSGC2204)the National Natural Science Foundation of China(82003787)Postdoctoral Innovation Project of Shandong Province。
文摘The ability to selectively introduce diverse functionality onto hydrocarbons is of substantial value in the synthesis of both small molecules and pharmaceuticals.In this endeavour,as a photocatalyst-and metalfree process,the electron donor–acceptor(EDA)strategy has not been well explored.Here we report an approach to aliphatic carbon-hydrogen bond diversification through an EDA complex constituted by HCl and S^(IV)=O groups.As an efficient hydrogen atom transfer(HAT)reagent,chlorine radical can be produced via a proton-coupled electron transfer process in this system.Based on this unusual path,a photopromoted versatile aliphatic C–H functionalization is developed without photo-and metal-catalysts,including thiolation,arylation,alkynylation,and allylation.This conversion has concise and ambient reaction conditions,good functional group tolerance,and substrate diversity,and provides an alternative solution for the high value-added utilization of bulk light alkanes.
基金supported by the Institute for Basic Science(IBS-R010-A2)。
文摘Bifunctional reagents that serve as dual coupling partners with an activating species have emerged as valuable synthetic tools in organic chemistry.They allow for the development of diverse reaction modes with enhanced efficiency and structural variability,which is in high demand for atom-economic and sustainable synthesis.Among them,bifunctional reagents containing Nheteroaryl groups have received much attention due to their ability to introduce privileged N-heteroaryl moieties into complex molecules that are otherwise challenging to access.Furthermore,these reagents have been employed under visible-light conditions to achieve various synthetic applications,enabling difunctionalization of alkenes,alkynes,and[1.1.1]propellanes under mild reaction conditions,providing access to highly functionalized N-heteroarenes.In this review,we provide an overview of the recent achievements and applications of photoinduced difunctionalization using bifunctional reagents containing N-heteroaryl groups.We systematically categorize the representative contributions in the field based on bifunctional reagents and their reactivity patterns.This review aims to highlight the potential of these reagents as powerful synthetic tools for sustainable and diverse synthesis.
基金This work was financially supported by the National Natural Science Foundation of China(grant nos.22122701,21731004,91953201,92153303,21977044,and 21907050)the Natural Science Foundation of Jiangsu Province(grant nos.BK20202004 and BK20190282)the Excellent Research Program of Nanjing University(grant no.ZYJH004).
文摘Photodynamic therapy(PDT)usually shows limited efficacy in solid tumors since traditional PDT is O_(2)^(-)dependent while solid tumors are inherently hypoxic.In addition,hypoxic tumor cells possess antiapoptotic pathways that resist PDT-induced apoptosis.Therefore,developing photosensitizers(PSs)that show low O_(2)^(-)dependency and can induce nonapoptotic cell death pathways is critically needed.Herein,a series of Ru(II)polypyridine complex-based PSs,RuNMe,RuH,and RuCN,were synthesized,and their applications against hypoxic tumor cells through PDT were investigated.All three complexes showthe ability to generate the superoxide anion radical(·O_(2)^(-)),which is the type I photoreaction and less O_(2)^(-)dependent.RuNMe shows the best PDT performance against MCF-7 cells and three-dimensional multicellular spheroids,due to its higher cellular uptake and more reactive oxygen species generation.More importantly,RuNMe-incubated MCF-7 cells show photoinduced ferroptosis as evidenced by glutathione peroxidase 4 downregulation and lipid peroxide accumulation.This work not only develops a novel ferroptosis-inducing Ru(II)complex with the type I PDT process but also offers an effective strategy to solve tumor hypoxia in PDT.
基金supported by the National Natural Science Foundation of China (21877011, 21576038, 21421005)the Fundamental Research Funds for the Central Universities of China (DUT16TD21)+1 种基金Science Program of Dalian City (2014J11JH133, 2015J12JH207)the Supercomputing Center of Dalian University of Technology
文摘Photochromic diarylethenes have been widely used in many fields. However, their cyclization process must be induced by UV light. In this article, a simple strategy is developed by extending π-conjugation with electron donating groups. The modified dirylethene derivative can photocyclolize under 405-nm light with a good photochromic efficiency. Meanwhile, its absorption and moderate fluorescence can be switched effectively in both directions by visible lights(405 and 520 nm, respectively) in different solutions and in living cells. We believe that this simple method will become a versatile strategy for developing various dirylethylenes with visible-light photochromism.
基金We are grateful to the financial supports from the National Natural Science Foundation of China （Nos. 20802013, 21002018, 21072038）, the Natural Scientific Research Innovation Foundation in Harbin institute of Technology （Nos. 01107866, 01107986） and the Wenzhou Science and Technology Program （No. G20100056）.
文摘The first example of the p-orbital overlap controlled enantioselectivity of Norrish type II photocyclization reaction was described. Irradiation of 5-methyl bicyclo[l. 1.1 ]pentanyl ketone with UV in the solid state as well as in the acetonitrile solution afforded the Norrish/Yang photocyclization compound as the sole product. Solid-state asymmetric photochemical studies using ionic chiral auxiliary technique led to the enantioselectivity as high as 60%. The results were rationalized by Xray single crystal structure.
文摘Organic matters in drinking water of Kaschin-Beck disease areas were extracted. Then analyses and characterization were performed by means of multiply chemical and physical methods. The results did not show the obvious difference in the frame structure of humic substances and the structure of rmcromolecular compounds in the drinking water of disease and non-disease areas, but the difference in the contents of some micromolecular compounds and radicals. The investigation also includes the preliminary research on the photoreaction of drinking water from disease and non-disease areas and the accumulation of natural organic matter in the bone of tested animals.
文摘An X-band EPR study on a Na_3(CrMo_6O_(24)H_6)·8H_2O single crystal diluted by its isomor-phic compound Na_3(AlMo_6O_(24)H_6)·8H_2O at room temperature is reported. Using the least squares-fitting method to simulate the EPR data for principal planes, the Hamiltonian parameterswere obtained. The principal values of the g tensors are g_(ZZ) = 1.904, g_(XX)= 1.973, g_(YY)=1.933. The zero field splitting tensor parameters are D = 0.275 cm^(-1), E = 0.05 cm^(-1). The fielddependence of Cr^(3+) energy levels with field at different angles from the principal axes whenthe field is along the principal planes is calculated based on these experimental parameters.The isofrequency plots of calculated field vs. angle are also shown. They agree well with theexperimental results.
基金Project supported by the National Natural Science Foundation of China
文摘Molecular design, synthesis and photochromic properties of spirooxazines and fulgides are described. In the case of fulgides, the change of the substituents may lead to different photochromic properties and different photoreactions of the kind of compounds. In photochromic process of pyrryl-substituted fulgides, the excited singlet state is the mam species, but the excited triplet state is also involved. However, no excited triplet state has been observed in cyclization of aryl-substituted fulgides. In the case of spirooxazines, the substituents at 2’-position have great effect on the formation of photoproduct and on the mechanism of photoreaction. The increase of steric hindrance of the 2’-position substituent gives rise to the decrease of the quantum yield for the formation of photochromic merocyanine (PMC) and the increase of the relative quantum yield for the charge separated twist intermediate (CT).
