Research on asymmetric A–D–A structured non-fullerene acceptors has lagged far behind the development of symmetric counterpart.In this contribution,by simply replacing one sulfur atom in indacenodithiophene unit wit...Research on asymmetric A–D–A structured non-fullerene acceptors has lagged far behind the development of symmetric counterpart.In this contribution,by simply replacing one sulfur atom in indacenodithiophene unit with a selenium atom,an asymmetric building block Se PT and a corresponding asymmetric non-fullerene acceptor Se PT-IN have been developed.Asymmetric Se PT-IN achieved a high efficiency of 10.20% in organic solar cells when blended with PBT1-C,much higher than that of symmetric TPT-IN counterpart(8.91%).Our results demonstrated an effective heteroatom substitution strategy to develop asymmetric A–D–A structured non-fullerene acceptors.展开更多
A new iodiplumbate/organic hybrid constructed from asymmetric viologen and polyiodides,(PBPY-H_2)_2[PbI_4(I_3)_2](1, PBPY = N-(propionate)-4,4?-bipyridinium), has been synthesized via solvothermal reaction and structu...A new iodiplumbate/organic hybrid constructed from asymmetric viologen and polyiodides,(PBPY-H_2)_2[PbI_4(I_3)_2](1, PBPY = N-(propionate)-4,4?-bipyridinium), has been synthesized via solvothermal reaction and structurally determined by X-ray diffraction method. Compound 1 crystallizes in monoclinic system, space group P21/c with Mr = 1936.72, a = 11.622(2), b = 14.839(3), c = 13.372(2) ?, β = 109.447(3)°, V = 2174.6(7) ?3, Z = 2, Dc = 2.958 g/cm3, F(000) = 1712, μ(Mo Kα) = 11.011 mm–1, the final R = 0.0389 and wR = 0.0854 for 3866 observed reflections with I > 2σ(I). [Pb I4(I3)2]4-mononuclear cluster of 1 features a seldom example of coordinated I-3 donors for the lead center. Intermolecular hydrogen bonds between [Pb I4+4(I3)2]-clusters and(PBPY-H)42 dimmers contribute to the formation of a 2-D layer. Its absorption spectrum was investigated, and lower energy band gap of 1.42 eV was explained by DFT calculation. Interestingly, 1 exhibits photocatalytic activity for the degradation of rhodamine B.展开更多
Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied,The effects of shake speed,hydrophobictiy of organic solvent ,v...Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied,The effects of shake speed,hydrophobictiy of organic solvent ,volume ratio of water phase to organic phase,pH value of aqueous phase and reaction temperature on the initial reaction rate,maximum yield and enantiomeric excess(ee) of the product were systematically explored,All the above-mentioned factors had significant infuence on the reaction.n-Hexane was found to be the best organic solvent for the reaction.The optimum shake speed,volume ratio of water phase to organic phase,pH value and reaction temperature were 150 r.min^-1,1/2,8 and 30℃ respectively,under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%,which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase ,To our best knowledge,this is the most satisfactory result obtained.展开更多
A series of chiral secondary alcohols were easily prepared by means of asymmetric hydrogenation of prochiral aromatic ketones using a new((R_(ax))-BuP)/(R,R)-DPEN-Ru(Ⅱ) complex catalyst system.The hydrogenation of 2-...A series of chiral secondary alcohols were easily prepared by means of asymmetric hydrogenation of prochiral aromatic ketones using a new((R_(ax))-BuP)/(R,R)-DPEN-Ru(Ⅱ) complex catalyst system.The hydrogenation of 2-methylacetophenone in n-butanol (t-BuOK/Ru =45.6/1,S/C = 500,20 atm.of H_2,20℃,48 h) afforded(S)-1-(2'-methylphenyl)ethanol in 92%ee and>99% conversion.展开更多
Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical properties.Sub...Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical properties.Substituted alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge transport.Here,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain length.Most importantly,a unique LUMO level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification properties.These results indicate that asymmetric side-chain engineering opens a route for breath healthcare.展开更多
Asymmetric-dimethylarginine(ADMA) competes with L-arginine for each of the three isoforms of nitric oxide synthase:endothelial;neuronal;inducible.ADMA is synthesized by protein methyltransferases followed by proteolyt...Asymmetric-dimethylarginine(ADMA) competes with L-arginine for each of the three isoforms of nitric oxide synthase:endothelial;neuronal;inducible.ADMA is synthesized by protein methyltransferases followed by proteolytic degradation.ADMA is metabolized to citrulline and dimethylamine,by dimethylarginine dimethylaminohydrolase(DDAH) and enters cells through cationic amino-acid transporters extensively expressed in the liver.The liver plays a crucial role in ADMA metabolism by DDAH-1 and,as has been recently demonstrated,it is also responsible for ADMA biliary excretion.A correlation has been demonstrated between plasma ADMA levels and the degree of hepatic dysfunction in patients suffering from liver diseases with varying aetiologies:plasma ADMA levels are increased in patients with liver cirrhosis,alcoholic hepatitis and acute liver failure.The mechanism by which liver dysfunction results in raised ADMA concentrations is probably due to impaired activity of DDAH due to severe inflammation,oxidative stress,and direct damage to DDAH.High plasma ADMA levels are also relevant as they are associated with the onset of multiorgan failure(MOF).Increased plasma concentration of ADMA was identified as an independent risk factor for MOF in critically-ill patients causing enhanced Intensive Care Unit mortality:a significant reduction in nitric oxide synthesis,leading to malperfusion in various organs,eventually culminating in multi organs dysfunction.展开更多
The optical α-amino acids were synthesized under room temperature byalkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phasetransfer conditions using polymer-supported cinchonine (or q...The optical α-amino acids were synthesized under room temperature byalkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phasetransfer conditions using polymer-supported cinchonine (or quinine) alkaloids as chiralphase transfer catalysts and dichloromethane as solvent, followed by hydrolysis of theabove intermediates introduced to the final products-optical α-amino acids. This is anew method for the asymmetric synthesis of α-amino acids. The influences of catalyst,temperature, substrates, and organic solvents on the chemical yield and optical purities ofproducts were studied.展开更多
Asymmetry has been demonstrated an effective approach in recent years to tune the structural and energetic orders of nonfullerene electron acceptors(NFAs)to prepare efficient organic solar cells(OSCs).In this article,...Asymmetry has been demonstrated an effective approach in recent years to tune the structural and energetic orders of nonfullerene electron acceptors(NFAs)to prepare efficient organic solar cells(OSCs).In this article,five asymmetric NFAs,namely C9BTP-BO-Th Cl-2F,C9BTP-BO-Cl-2F,C9BTP-BO-2Cl-2F,C7BTP-BO-2Cl-2F and C5BTP-BO-2Cl-2F possessing varied asymmetric end-groups and alkyl chains are synthesized to tune the charge transport networks formed within these NFAs.We found that the enhanced planarity in the asymmetric NFA can facilitate closerπ-πstacking distance in either the A-to-A or A-toD type NFA dimers,whilst the larger dipole moment can promote the formation of three-dimensional(3D)charge transport networks among NFAs.Taking those advantages,C7BTP-BO-2Cl-2F exhibit a compact 3D honeycomb network with a high packing coefficient of 72.1%and molecular packing density of 0.48 g/cm^(3),contributing to a superior power conversion efficiency of 18.0%when employing PM6 as the donor,with an open-circuit voltage of 0.85 V,short-circuit current of26.7 m A cm^(-2)and fill factor of 79.3%.Our work provides guidelines in engineering the end group and side chains of asymmetric NFAs to achieve compact charge transport networks for high efficiency OSCs.展开更多
A series of novel atropisomeric diphosphine ligands termed Tan Phos were designed and synthesized,which has a smaller bite angle compared with that of other ligands such as BINAP.Tan Phos showed high reactivity and en...A series of novel atropisomeric diphosphine ligands termed Tan Phos were designed and synthesized,which has a smaller bite angle compared with that of other ligands such as BINAP.Tan Phos showed high reactivity and enantioselectivity in the rhodiumcatalyzed asymmetric hydrogenation ofα-dehydro amino ketones,and up 99%yield and 99%ee were obtained for a wide range of chiralα-amino ketones.展开更多
Narrow bandgap non-fullerene acceptors(NFAs)are relevant as key materials components for the fabrication of near-infrared(NIR)organic solar cells(OSCs)and organic photodiodes(OPDs)thanks to their complementary absorpt...Narrow bandgap non-fullerene acceptors(NFAs)are relevant as key materials components for the fabrication of near-infrared(NIR)organic solar cells(OSCs)and organic photodiodes(OPDs)thanks to their complementary absorption,tunable energy levels,and enhanced stability.However,high-performance NIR photodetectors are still scarce due to the absence of narrow bandgap NFAs.Herein,an asymmetric A-D-π-A type NFA,named ABTPV-S,with a broad optical absorption approaching 1,000 nm is designed and synthesized through integrating alkylthio side chains and a vinyleneπ-bridge.The optimal inverted OPD device exhibits an excellent performance with a photoresponsivity of 0.39 AW-1,a noise current of 2.25×10^(-14)A Hz^(-0.5),a specific detectivity(D*)of 3.43×10^(12)Jones at 840 nm,and linear dynamic range(LDR)of 140 d B.In addition,the rise and fall times for ABTPV-S-based OPDs also reach 1.07 and 0.71μs,respectively.ABTPV-S-based OPDs exhibit a high D*over 1012Jones at 950 nm,which is a competitive result for the self-powered photodiode-type NIR OPDs.These findings highlight the outstanding potential of asymmetric A-D-π-A type NIR NFAs for high-performance OPDs competing with their silicon counterparts.展开更多
Nonfullerene acceptors(NFAs),which usually possess symmetric skeletons,have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts.Moreover,breaking the symmetry of NF...Nonfullerene acceptors(NFAs),which usually possess symmetric skeletons,have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts.Moreover,breaking the symmetry of NFAs could fine tune the molecular dipole,solubility,energy level,intermolecular interaction,molecular packing,crystallinity,etc.,and give rise to improved photovoltaic performance.Currently,there are three main strategies for the design of asymmetric NFAs.This review highlights the recent advances of high-performance asymmetric NFAs and briefly outlooks the materials exploration for the future.展开更多
基金financially supported by the National Natural Science Foundation of China (NSFC) (Nos. 21674007 and 21734001)the financial support from National Research Foundation (NRF) of Korea (2012M3A6A7055540 and 2015M1A2A2057506)
文摘Research on asymmetric A–D–A structured non-fullerene acceptors has lagged far behind the development of symmetric counterpart.In this contribution,by simply replacing one sulfur atom in indacenodithiophene unit with a selenium atom,an asymmetric building block Se PT and a corresponding asymmetric non-fullerene acceptor Se PT-IN have been developed.Asymmetric Se PT-IN achieved a high efficiency of 10.20% in organic solar cells when blended with PBT1-C,much higher than that of symmetric TPT-IN counterpart(8.91%).Our results demonstrated an effective heteroatom substitution strategy to develop asymmetric A–D–A structured non-fullerene acceptors.
基金Project supported by the National Natural Science Foundation of China(21271043,21771038)Qishan Scholars Program of Fuzhou University(No.XQS-1403)
文摘A new iodiplumbate/organic hybrid constructed from asymmetric viologen and polyiodides,(PBPY-H_2)_2[PbI_4(I_3)_2](1, PBPY = N-(propionate)-4,4?-bipyridinium), has been synthesized via solvothermal reaction and structurally determined by X-ray diffraction method. Compound 1 crystallizes in monoclinic system, space group P21/c with Mr = 1936.72, a = 11.622(2), b = 14.839(3), c = 13.372(2) ?, β = 109.447(3)°, V = 2174.6(7) ?3, Z = 2, Dc = 2.958 g/cm3, F(000) = 1712, μ(Mo Kα) = 11.011 mm–1, the final R = 0.0389 and wR = 0.0854 for 3866 observed reflections with I > 2σ(I). [Pb I4(I3)2]4-mononuclear cluster of 1 features a seldom example of coordinated I-3 donors for the lead center. Intermolecular hydrogen bonds between [Pb I4+4(I3)2]-clusters and(PBPY-H)42 dimmers contribute to the formation of a 2-D layer. Its absorption spectrum was investigated, and lower energy band gap of 1.42 eV was explained by DFT calculation. Interestingly, 1 exhibits photocatalytic activity for the degradation of rhodamine B.
基金Supported by the National Natural Science Foundation of China(No.20076019)the Natural Science Foundation of Guang-dong Province(No.000444).
文摘Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied,The effects of shake speed,hydrophobictiy of organic solvent ,volume ratio of water phase to organic phase,pH value of aqueous phase and reaction temperature on the initial reaction rate,maximum yield and enantiomeric excess(ee) of the product were systematically explored,All the above-mentioned factors had significant infuence on the reaction.n-Hexane was found to be the best organic solvent for the reaction.The optimum shake speed,volume ratio of water phase to organic phase,pH value and reaction temperature were 150 r.min^-1,1/2,8 and 30℃ respectively,under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%,which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase ,To our best knowledge,this is the most satisfactory result obtained.
基金the National Natural Science Foundation of China(Nos.20343005,20473107,20673130,and 20773147)the Hong Kong PolyU Joint Supervision Scheme(A-PH78) for financial support.
文摘A series of chiral secondary alcohols were easily prepared by means of asymmetric hydrogenation of prochiral aromatic ketones using a new((R_(ax))-BuP)/(R,R)-DPEN-Ru(Ⅱ) complex catalyst system.The hydrogenation of 2-methylacetophenone in n-butanol (t-BuOK/Ru =45.6/1,S/C = 500,20 atm.of H_2,20℃,48 h) afforded(S)-1-(2'-methylphenyl)ethanol in 92%ee and>99% conversion.
基金financially supported by the National Natural Science Foundation of China(Nos.6197396,21905276)Natural Science Foundation of Beijing(No.4202077)+1 种基金Chinese Academy of Scinece(No.ZDBS-LY-SLH034)the Fundamental Research Funds for the Central Universities(No.E2ET0309X2)。
文摘Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical properties.Substituted alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge transport.Here,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain length.Most importantly,a unique LUMO level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification properties.These results indicate that asymmetric side-chain engineering opens a route for breath healthcare.
文摘Asymmetric-dimethylarginine(ADMA) competes with L-arginine for each of the three isoforms of nitric oxide synthase:endothelial;neuronal;inducible.ADMA is synthesized by protein methyltransferases followed by proteolytic degradation.ADMA is metabolized to citrulline and dimethylamine,by dimethylarginine dimethylaminohydrolase(DDAH) and enters cells through cationic amino-acid transporters extensively expressed in the liver.The liver plays a crucial role in ADMA metabolism by DDAH-1 and,as has been recently demonstrated,it is also responsible for ADMA biliary excretion.A correlation has been demonstrated between plasma ADMA levels and the degree of hepatic dysfunction in patients suffering from liver diseases with varying aetiologies:plasma ADMA levels are increased in patients with liver cirrhosis,alcoholic hepatitis and acute liver failure.The mechanism by which liver dysfunction results in raised ADMA concentrations is probably due to impaired activity of DDAH due to severe inflammation,oxidative stress,and direct damage to DDAH.High plasma ADMA levels are also relevant as they are associated with the onset of multiorgan failure(MOF).Increased plasma concentration of ADMA was identified as an independent risk factor for MOF in critically-ill patients causing enhanced Intensive Care Unit mortality:a significant reduction in nitric oxide synthesis,leading to malperfusion in various organs,eventually culminating in multi organs dysfunction.
基金Project supported by State Education Committee Initial Research Crams for Return Scholar and supported by NSFC No 29774012.
文摘The optical α-amino acids were synthesized under room temperature byalkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phasetransfer conditions using polymer-supported cinchonine (or quinine) alkaloids as chiralphase transfer catalysts and dichloromethane as solvent, followed by hydrolysis of theabove intermediates introduced to the final products-optical α-amino acids. This is anew method for the asymmetric synthesis of α-amino acids. The influences of catalyst,temperature, substrates, and organic solvents on the chemical yield and optical purities ofproducts were studied.
基金supported by the National Natural Science Foundation of China(52073221,52273196)。
文摘Asymmetry has been demonstrated an effective approach in recent years to tune the structural and energetic orders of nonfullerene electron acceptors(NFAs)to prepare efficient organic solar cells(OSCs).In this article,five asymmetric NFAs,namely C9BTP-BO-Th Cl-2F,C9BTP-BO-Cl-2F,C9BTP-BO-2Cl-2F,C7BTP-BO-2Cl-2F and C5BTP-BO-2Cl-2F possessing varied asymmetric end-groups and alkyl chains are synthesized to tune the charge transport networks formed within these NFAs.We found that the enhanced planarity in the asymmetric NFA can facilitate closerπ-πstacking distance in either the A-to-A or A-toD type NFA dimers,whilst the larger dipole moment can promote the formation of three-dimensional(3D)charge transport networks among NFAs.Taking those advantages,C7BTP-BO-2Cl-2F exhibit a compact 3D honeycomb network with a high packing coefficient of 72.1%and molecular packing density of 0.48 g/cm^(3),contributing to a superior power conversion efficiency of 18.0%when employing PM6 as the donor,with an open-circuit voltage of 0.85 V,short-circuit current of26.7 m A cm^(-2)and fill factor of 79.3%.Our work provides guidelines in engineering the end group and side chains of asymmetric NFAs to achieve compact charge transport networks for high efficiency OSCs.
基金the National Key R&D Program of China(2021YFA1500201)the Stable Support Plan Program of Shenzhen Natural Science Fund(20200925161222002)+5 种基金the Key-Area Research and Development Program of Guangdong Province(2020B010188001)the Innovative Team of Universities in Guangdong Province(2020KCXTD016)the National Natural Science Foundation of China(21991113)the Guangdong Basic and Applied Basic Research Foundation(2022B1515020055)the National Natural Science Foundation of China(22171129)Shenzhen Science and Technology Innovation Committee(JCYJ20210324104202007)for financial support。
文摘A series of novel atropisomeric diphosphine ligands termed Tan Phos were designed and synthesized,which has a smaller bite angle compared with that of other ligands such as BINAP.Tan Phos showed high reactivity and enantioselectivity in the rhodiumcatalyzed asymmetric hydrogenation ofα-dehydro amino ketones,and up 99%yield and 99%ee were obtained for a wide range of chiralα-amino ketones.
基金supported by the National Natural Science Foundation of China(21905137)the Basic Ability Improvement Project for Young and Middle-aged University Teachers of Guangxi(2022KY0256)。
文摘Narrow bandgap non-fullerene acceptors(NFAs)are relevant as key materials components for the fabrication of near-infrared(NIR)organic solar cells(OSCs)and organic photodiodes(OPDs)thanks to their complementary absorption,tunable energy levels,and enhanced stability.However,high-performance NIR photodetectors are still scarce due to the absence of narrow bandgap NFAs.Herein,an asymmetric A-D-π-A type NFA,named ABTPV-S,with a broad optical absorption approaching 1,000 nm is designed and synthesized through integrating alkylthio side chains and a vinyleneπ-bridge.The optimal inverted OPD device exhibits an excellent performance with a photoresponsivity of 0.39 AW-1,a noise current of 2.25×10^(-14)A Hz^(-0.5),a specific detectivity(D*)of 3.43×10^(12)Jones at 840 nm,and linear dynamic range(LDR)of 140 d B.In addition,the rise and fall times for ABTPV-S-based OPDs also reach 1.07 and 0.71μs,respectively.ABTPV-S-based OPDs exhibit a high D*over 1012Jones at 950 nm,which is a competitive result for the self-powered photodiode-type NIR OPDs.These findings highlight the outstanding potential of asymmetric A-D-π-A type NIR NFAs for high-performance OPDs competing with their silicon counterparts.
基金supported by the National Natural Science Foundation of China(Nos.22075069,51933001)Natural Science Foundation of Henan Province(No.212300410002)Program sponsored by Henan Province(Nos.23ZX002,ZYQR201912163).
文摘Nonfullerene acceptors(NFAs),which usually possess symmetric skeletons,have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts.Moreover,breaking the symmetry of NFAs could fine tune the molecular dipole,solubility,energy level,intermolecular interaction,molecular packing,crystallinity,etc.,and give rise to improved photovoltaic performance.Currently,there are three main strategies for the design of asymmetric NFAs.This review highlights the recent advances of high-performance asymmetric NFAs and briefly outlooks the materials exploration for the future.
