Palladium-catalyzed carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacol-borate were successfully conducted in the absence of any extra ligand to produce β,γ-unsaturated esters in satisfact...Palladium-catalyzed carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacol-borate were successfully conducted in the absence of any extra ligand to produce β,γ-unsaturated esters in satisfactory to good yields. The carboxylative Suzuki coupling reaction proceeded smooth-ly under mild conditions in the presence of palladium nanoparticles generated in situ through the formation of a π-benzylpalladium chloride intermediate.展开更多
A novel bromination of α,β-unsaturated carboxylic acids was developed via a decarboxylation by virtue of a direct anodic electro-oxidation.In this method,ammonium bromide was employed as a bromine source and the rea...A novel bromination of α,β-unsaturated carboxylic acids was developed via a decarboxylation by virtue of a direct anodic electro-oxidation.In this method,ammonium bromide was employed as a bromine source and the reaction features transition-metal-free,short time,and no additional supporting electrolyte.展开更多
The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative...The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative cyclization of a variety of alkynic hydrazones with carbon dioxide to produce the corresponding 1,3,4-oxadiazin-2-ones under mild reaction conditions. In this reaction, silver(I) salts play a π-Lewis acid role for the highly efficient activation of the alkyne moiety in the hydrazone substrates. Single-crystal X-ray analysis and NOE experiments confirm that the newly formed oxadiazinone products exhibit Z configuration. Based on control experiments and NMR studies, a mechanism including the formation of a reactive carbazate intermediate, electrophilic cyclization, and subsequent protonation is proposed. This study offers an efficient and atom- economical method for the synthesis of biologically important 1,3,4-oxadiazin-2-ones.展开更多
A novel and general carbon-nitrogen and carbon-carbon cross-coupling reaction between 3,4-dihydropyrimidine-2-thiones and copper(Ⅰ) carboxylates were performed in the presence of palladium acetate.The copper(Ⅰ) ...A novel and general carbon-nitrogen and carbon-carbon cross-coupling reaction between 3,4-dihydropyrimidine-2-thiones and copper(Ⅰ) carboxylates were performed in the presence of palladium acetate.The copper(Ⅰ) carboxylates act not only as desulfurative reagents but also as sources of carbon nudeophiles.A wide array of highly substituted and functionalized pyrimidines scaffolds were synthesized in good yields.展开更多
Silver-catalyzed decarboxylative C–H alkylation of cyclic aldimines with abundant aliphatic carboxylic acids has been realized under mild reaction conditions generating the corresponding products in moderate to good ...Silver-catalyzed decarboxylative C–H alkylation of cyclic aldimines with abundant aliphatic carboxylic acids has been realized under mild reaction conditions generating the corresponding products in moderate to good yields(32%–91%).In addition,a gram-scale reaction,late-stage modification of drug,synthetic transformation of the product,and further application of the catalytic strategy were also performed.Preliminary studies indicate that the reaction undergoes a radical process.展开更多
We report a tandem asymmetric Cu-catalyzed propargylic amination(ACPA)/Ag-catalyzed carboxylative cyclization(SCC)with CO_(2) to 5-methylidene-2-oxazolidinones;even with tetrasubstituted stereocenters.By varying pyrid...We report a tandem asymmetric Cu-catalyzed propargylic amination(ACPA)/Ag-catalyzed carboxylative cyclization(SCC)with CO_(2) to 5-methylidene-2-oxazolidinones;even with tetrasubstituted stereocenters.By varying pyridine bisoxazoline(PYBOX)ligands;a general and highly enantioselective ACPA of unprecedentedly broad scope of secondary propargylic acetates and primary amines is achieved.Bothα-aryl andα-aliphatic propargylic acetates could react with either aromatic or aliphatic primary amines to give the corresponding N-aryl or N-aliphatic ethynylamines withα-aliphatic orα-aryl groups in over 90%ee for use in the next step.The key to developing this one-pot sequence is to use a chelator triethylenetetramine(TETA)to mask the copper ion;to avoid its negative effect on Ag-catalyzed cyclization;whilst releasing PYBOX to activate the silver catalyst.With the methylidene moiety;these oxazolidinones can be readily elaborated.The value of the sequence is further shown by the catalytic enantioselective total synthesis of(–)-cytoxazone and the potent ezetimibe analogue.展开更多
In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines.The protocol is performed at mild conditions without the use of noble metals as ca...In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines.The protocol is performed at mild conditions without the use of noble metals as catalysts.A wide range of structurally diverse secondary amines could be obtained in good yields(up to 94%)with good functional group tolerance.This transformation shows good to excellent selectivity,avoiding the generation of over alkylated byproducts.展开更多
Boronate esters are highly valued in synthetic and pharmaceutical industries for their versatility in creating C—C and C—X bonds.They also find applications as catalysts in chemical transformations as well as stimul...Boronate esters are highly valued in synthetic and pharmaceutical industries for their versatility in creating C—C and C—X bonds.They also find applications as catalysts in chemical transformations as well as stimuli-responsive materials in materials science.Some alkyl boronates themselves also show promising applications in medicinal chemistry.In the past few decades,chemists have been devoted to developing new methods or new starting materials for synthesizing boronate esters.Carboxylic acids and their derivatives are privileged chemical entities due to their readily availability or natural abundance,structural diversity,and chemical stability.Hence,the transformation of carboxylic acid and their derivatives to alkyl/aryl boronate esters has seen its fast development in the past decade.This review summarized the state-to-art development of decarboxylative and decarbonylative borylation of carboxylic acids and their derivatives to aryl and alkyl boronate esters.展开更多
The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed...The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.展开更多
Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O soluti...Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.展开更多
Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high ...Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high BET and surface defects.Additionally,the sodium storage mechanism predominantly occurs in the slope region.This contradicts practical application requirements because the capacity of the plateau region is crucial for determining the actual capacity of batteries.In our work,we prepared a novel“core-shell”carbon framework(CNA1200).Introducingclosedporesand carboxylgroupsinto coal-basedcarbon materials to enhance its sodium storage performance.The closed pore structure dominates in the“core”structure,which is attributed to the timely removal of sodium hydroxide(NaOH)to prevent further for-mation of active carbon structure.The presence of closed pores is beneficial for increasing sodium ion storage in the low-voltage plateau region.And the“shell”structure originates from coal tar pitch,it not only uniformly connects hard carbon particles together to improve cycling stability,but is also rich in carboxyl groups to enhance the reversible sodium storage performance in slope region.CNA1200 has ex-cellent electrochemical performance,it exhibits a specific capacity of 335.2 mAh g^(−1)at a current density of 20 mA g^(−1)with ICE=51.53%.In addition,CNA1200 has outstanding cycling stability with a capac-ity retention of 91.8%even when cycling over 200 times.When CNA1200 is used as anode paired with Na_(3)V_(2)(PO_(4))_(3)cathode,it demonstrates a capacity of 109.54 mAh g^(−1)at 0.1 C and capacity retention of 94.64%at 0.5 C.This work provides valuable methods for regulating the structure of sodium-ion battery(SIBs)anode and enhances the potential for commercialization.展开更多
A carboxylative coupling reaction of various primary amine and 3-phenyl-2-propynyl or 2-nonynyl chloride in the presence of 8-diazabicyclo[5.4.0]undec-7-ene(DBU)using carbon dioxide as carboxylative reagent was presen...A carboxylative coupling reaction of various primary amine and 3-phenyl-2-propynyl or 2-nonynyl chloride in the presence of 8-diazabicyclo[5.4.0]undec-7-ene(DBU)using carbon dioxide as carboxylative reagent was presented.This transition-metal free reaction system shows broad substrate scope and gives a series of propargylcarbamates in moderate to good yield.The obtained N-alkyl substituted carbamate product can undergo base-catalyzed intramolecular cyclization reaction to afford functionalized 4-methylene-2-oxazolidinone in good yield.展开更多
A copper-catalyzed decarboxylative oxidative coupling of α,β-unsaturated carboxylic acids with non-cyclic ethers is developed.This method provides a new approach for C(sp^3)–H bond functionalization of non-cyclic e...A copper-catalyzed decarboxylative oxidative coupling of α,β-unsaturated carboxylic acids with non-cyclic ethers is developed.This method provides a new approach for C(sp^3)–H bond functionalization of non-cyclic ethers. Mechanism study shows the reaction involves a radical process.展开更多
Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are o...Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.展开更多
Ketones serve as one of the most critical building blocks in organic synthesis,involving numerous functional group transformations.Herein,we rep ort an unprecedented photoredox-nickel metallap hotoredox-catalyzed deca...Ketones serve as one of the most critical building blocks in organic synthesis,involving numerous functional group transformations.Herein,we rep ort an unprecedented photoredox-nickel metallap hotoredox-catalyzed decarboxylative acylation of common aliphatic acids with readily available aromatic and aliphatic thioesters.A wide range of structurally diverse asymmetrical aryl alkyl and dialkyl ketones have been constructed in yields of up to 98% with this strategy.The protocol has excellent reaction selectivity and functional group compatibility,representing a significant step forward in ketone synthesis.The one-pot decarboxylative acylation at the gram scale from two different carboxylic acids and the late-stage application for the synthesis of complex ketones shows its synthetic robustness.Both mechanistic experiments and density functional theory(DFT)calculations suggest that the decarboxylative acylation reaction operates via an underdeveloped Ni(Ⅰ)-Ni(Ⅱ)-Ni(Ⅰ)-Ni(Ⅲ)-Ni(Ⅰ)catalytic cycle.展开更多
An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acylox...An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature.展开更多
Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)...Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.展开更多
A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assig...A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.展开更多
Microbial consortia that catalyze chain elongation processes have been enriched using different selection strategies,for which the electron donor is an essential one.Propanol is an extraordinarily promising electron d...Microbial consortia that catalyze chain elongation processes have been enriched using different selection strategies,for which the electron donor is an essential one.Propanol is an extraordinarily promising electron donor because it can be generated from renewable resources,including lignocellulosic biomass and protein wastes.Here,propanol was proven in detail to be an efficient electron donor,enhancing the production of odd medium-chain carboxylates during chain elongation.By exploring various electron acceptors,reactor conditions,and electron donor/electron acceptor mol ratios,our study highlights that acetate is the most suitable electron acceptor for the production of both odd-and even-chain carboxylates.The optimal conditions for propanol-based chain elongation were 30℃ and pH 6,achieving 82.8%selectivity for odd-chain carboxylates.Another critical insight from our work is that a propanol/acetate mol ratio of 1:1 can minimize the inhibitory effect of propanol and maximize the yield of medium-chain carboxylates,with the highest concentration of n-heptanoate reaching 124.5 mmol C/L.This was further illustrated by 16S rRNA amplicon sequencing,which elucidated that the community composition and keystone species in a propanol-based reactor closely resembled that of the ethanol one.The dominant phylum of the propanol-based reactor,Firmicutes showed a significant positive correlation with the concentrations of n-caproate and n-valerate.Additionally,the co-occurrence of Clostridium sensu stricto 12 and Oscillibacter,known as typical chain elongators,was identified within the propanol-based reactor.These findings enhance our understanding of propanolbased chain elongation,offer guiding principles for reactor microbiota assembly,and support efficient odd medium-chain carboxylate production.展开更多
Unconventional natural gas has become an important supplement to conventional energy sources,and the process of enrichment and purification of methane from low concentration coalbed methane is crucial.To this end,we r...Unconventional natural gas has become an important supplement to conventional energy sources,and the process of enrichment and purification of methane from low concentration coalbed methane is crucial.To this end,we report a copper-based metal-organic framework(MOF),ZJNU-119Cu,featuring two methane traps constructed with uncoordinated carboxylic acid oxygens and open metal sites.ZJNU-119Cu exhibits a high methane adsorption capacity(58.2 cm^(3)·g^(-1))at 298 K and 0.1 MPa and excellent CH_(4)/N_(2) separation performance under dynamic conditions.Densityfunctional theory calculations combined with grand canonical Monte Carlo simulation theory reveal the interaction mechanism for the uncoordinated carboxylic acid oxygen atoms and open metal sites in ZJNU-119Cu with CH4.The gas adsorption isotherms,heat of adsorption calculations,and breakthrough separation experiments indicate that this MOF is a very promising adsorbent for CH_(4)/N_(2) separation.展开更多
文摘Palladium-catalyzed carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacol-borate were successfully conducted in the absence of any extra ligand to produce β,γ-unsaturated esters in satisfactory to good yields. The carboxylative Suzuki coupling reaction proceeded smooth-ly under mild conditions in the presence of palladium nanoparticles generated in situ through the formation of a π-benzylpalladium chloride intermediate.
基金the National Nature Science Foundation of China(Nos.21472177,21672200,21432009,J1310010)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20000000)
文摘A novel bromination of α,β-unsaturated carboxylic acids was developed via a decarboxylation by virtue of a direct anodic electro-oxidation.In this method,ammonium bromide was employed as a bromine source and the reaction features transition-metal-free,short time,and no additional supporting electrolyte.
基金supported by the National Natural Science Foundation of China(21878038)the Natural Science Foundation of Liaoning Province(20170540156)the Program for Changjiang Scholars and Innovative Research Team in University(IRT-17R14)~~
文摘The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative cyclization of a variety of alkynic hydrazones with carbon dioxide to produce the corresponding 1,3,4-oxadiazin-2-ones under mild reaction conditions. In this reaction, silver(I) salts play a π-Lewis acid role for the highly efficient activation of the alkyne moiety in the hydrazone substrates. Single-crystal X-ray analysis and NOE experiments confirm that the newly formed oxadiazinone products exhibit Z configuration. Based on control experiments and NMR studies, a mechanism including the formation of a reactive carbazate intermediate, electrophilic cyclization, and subsequent protonation is proposed. This study offers an efficient and atom- economical method for the synthesis of biologically important 1,3,4-oxadiazin-2-ones.
基金Financial support from the National Natural Science Foundation of China(Nos.21362032 and 21362031)the NSF of Gansu Province(No.1208RJYA083)
文摘A novel and general carbon-nitrogen and carbon-carbon cross-coupling reaction between 3,4-dihydropyrimidine-2-thiones and copper(Ⅰ) carboxylates were performed in the presence of palladium acetate.The copper(Ⅰ) carboxylates act not only as desulfurative reagents but also as sources of carbon nudeophiles.A wide array of highly substituted and functionalized pyrimidines scaffolds were synthesized in good yields.
基金financially supported by the National Natural Science Foundation of China(Nos.21402116,21502111,21572126)the Science and Technology Innovation Talents of Henan Province(No.2018JQ0011)the Key Science Research of Education Committee in Henan Province(No.21A150044)。
文摘Silver-catalyzed decarboxylative C–H alkylation of cyclic aldimines with abundant aliphatic carboxylic acids has been realized under mild reaction conditions generating the corresponding products in moderate to good yields(32%–91%).In addition,a gram-scale reaction,late-stage modification of drug,synthetic transformation of the product,and further application of the catalytic strategy were also performed.Preliminary studies indicate that the reaction undergoes a radical process.
基金supported by the National Natural Science Foundation of China(21871090,21725203)the National Key Research and Development Program of China(2020YFA0710200)+2 种基金the Shanghai Science and Technology Innovation Action Plan(20JC1416900)the Innovation Program of Shanghai Municipal Education Commission(2023ZKZD37)the Fundamental Research Funds for the Central Universities.
文摘We report a tandem asymmetric Cu-catalyzed propargylic amination(ACPA)/Ag-catalyzed carboxylative cyclization(SCC)with CO_(2) to 5-methylidene-2-oxazolidinones;even with tetrasubstituted stereocenters.By varying pyridine bisoxazoline(PYBOX)ligands;a general and highly enantioselective ACPA of unprecedentedly broad scope of secondary propargylic acetates and primary amines is achieved.Bothα-aryl andα-aliphatic propargylic acetates could react with either aromatic or aliphatic primary amines to give the corresponding N-aryl or N-aliphatic ethynylamines withα-aliphatic orα-aryl groups in over 90%ee for use in the next step.The key to developing this one-pot sequence is to use a chelator triethylenetetramine(TETA)to mask the copper ion;to avoid its negative effect on Ag-catalyzed cyclization;whilst releasing PYBOX to activate the silver catalyst.With the methylidene moiety;these oxazolidinones can be readily elaborated.The value of the sequence is further shown by the catalytic enantioselective total synthesis of(–)-cytoxazone and the potent ezetimibe analogue.
基金National Key Research and Development Program of China(2022YFA1503200,2021YFC2101901)the National Natural Science Foundation of China(22122103,22101130,22001117,21971108,22271144)Fundamental Research Funds for the Central Universities(020514380304,020514380252,020514380272)for financial support.
文摘In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines.The protocol is performed at mild conditions without the use of noble metals as catalysts.A wide range of structurally diverse secondary amines could be obtained in good yields(up to 94%)with good functional group tolerance.This transformation shows good to excellent selectivity,avoiding the generation of over alkylated byproducts.
基金the National Natural Science Foundation of China(22271295)Gansu Provincial Natural Science Foundation Key Project(23JRRA606)+1 种基金Major Program of the Lanzhou Institute of Chemical Physics,CAS(No.ZYFZFX-9)State Key Laboratory Program of the Lanzhou Institute of Chemical Physics(CHGZ-202208)for generous financial support.
文摘Boronate esters are highly valued in synthetic and pharmaceutical industries for their versatility in creating C—C and C—X bonds.They also find applications as catalysts in chemical transformations as well as stimuli-responsive materials in materials science.Some alkyl boronates themselves also show promising applications in medicinal chemistry.In the past few decades,chemists have been devoted to developing new methods or new starting materials for synthesizing boronate esters.Carboxylic acids and their derivatives are privileged chemical entities due to their readily availability or natural abundance,structural diversity,and chemical stability.Hence,the transformation of carboxylic acid and their derivatives to alkyl/aryl boronate esters has seen its fast development in the past decade.This review summarized the state-to-art development of decarboxylative and decarbonylative borylation of carboxylic acids and their derivatives to aryl and alkyl boronate esters.
基金supported by the National Natural Science Foundation of China,Nos.91849115 and U1904207(to YX),81974211 and 82171247(to CS)Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences,No.2020-PT310-01(to YX).
文摘The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.
文摘Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.
基金the National Natural Science Foundation of China(No.21978164,22078189 and 22105120)the Outstanding Youth Science Fund of Shaanxi Province(No.2021JC-046)and the Special Support Program for high level talents of Shaanxi Province+3 种基金the Innovation Support Program of Shaanxi Province(2021JZY-001)the Key Research and Development Program of Shaanxi Province(No.2020GY-243)the Special Research Fund of Education Department of Shaanxi(No.20JK0535)the National High-end Foreign Expert Project(No.GDW20186100428).
文摘Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high BET and surface defects.Additionally,the sodium storage mechanism predominantly occurs in the slope region.This contradicts practical application requirements because the capacity of the plateau region is crucial for determining the actual capacity of batteries.In our work,we prepared a novel“core-shell”carbon framework(CNA1200).Introducingclosedporesand carboxylgroupsinto coal-basedcarbon materials to enhance its sodium storage performance.The closed pore structure dominates in the“core”structure,which is attributed to the timely removal of sodium hydroxide(NaOH)to prevent further for-mation of active carbon structure.The presence of closed pores is beneficial for increasing sodium ion storage in the low-voltage plateau region.And the“shell”structure originates from coal tar pitch,it not only uniformly connects hard carbon particles together to improve cycling stability,but is also rich in carboxyl groups to enhance the reversible sodium storage performance in slope region.CNA1200 has ex-cellent electrochemical performance,it exhibits a specific capacity of 335.2 mAh g^(−1)at a current density of 20 mA g^(−1)with ICE=51.53%.In addition,CNA1200 has outstanding cycling stability with a capac-ity retention of 91.8%even when cycling over 200 times.When CNA1200 is used as anode paired with Na_(3)V_(2)(PO_(4))_(3)cathode,it demonstrates a capacity of 109.54 mAh g^(−1)at 0.1 C and capacity retention of 94.64%at 0.5 C.This work provides valuable methods for regulating the structure of sodium-ion battery(SIBs)anode and enhances the potential for commercialization.
基金National Natural Science Foundation of China(No.21172026)Scientific Research Fund of Liaoning Provincial Education Department(No.L2012024)X.-B.L.gratefully acknowledges the Chang Jiang Scholars Program(No.T2011056)from Ministry of Education of the People's Republic of China.
文摘A carboxylative coupling reaction of various primary amine and 3-phenyl-2-propynyl or 2-nonynyl chloride in the presence of 8-diazabicyclo[5.4.0]undec-7-ene(DBU)using carbon dioxide as carboxylative reagent was presented.This transition-metal free reaction system shows broad substrate scope and gives a series of propargylcarbamates in moderate to good yield.The obtained N-alkyl substituted carbamate product can undergo base-catalyzed intramolecular cyclization reaction to afford functionalized 4-methylene-2-oxazolidinone in good yield.
基金supported by the National Natural Science Foundation of China (21572240)
文摘A copper-catalyzed decarboxylative oxidative coupling of α,β-unsaturated carboxylic acids with non-cyclic ethers is developed.This method provides a new approach for C(sp^3)–H bond functionalization of non-cyclic ethers. Mechanism study shows the reaction involves a radical process.
基金supported by LifeArc Philanthropic Fund(P2019-0004)LifeArc Pathfinder Award+7 种基金along with Wellcome Trust Seed Award(109626/Z/15/Z)FA PESP-UoB Strategic Collaboration FundBirmingham Fellowship(to SS)grants from Laboratoire d'Excellence Revive(Investissement d'AvenirANR-10-LABX-73)the Region lle-de-France via doctoral school Innovation Therapeutique,du Fondamentalàl'Appliqué(ED569)from Universite Paris-Saclay(to LA)Medical Research Council(MRC)Developmental Pathway Funding Scheme(DPFS)grant(MR/P007732/1)(to TB)supported by the Association Fran?aise contre les Myopathies(AFM-Téléthon)。
文摘Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.
基金the financial support from the National Natural Science Foundation of China(grant nos.22001117,21971108,21971111,and 21732003)the Natural Science Foundation of Jiangsu Province(grant no.BK20190006)+1 种基金Fundamental Research Funds for the Central Universities(0205/14380252),“Innovation&Entrepreneurship Talents Plan”of Jiangsu ProvinceFoundation of Advanced Catalytic Engineering Research Center of the Ministry of Education of Hunan University.
文摘Ketones serve as one of the most critical building blocks in organic synthesis,involving numerous functional group transformations.Herein,we rep ort an unprecedented photoredox-nickel metallap hotoredox-catalyzed decarboxylative acylation of common aliphatic acids with readily available aromatic and aliphatic thioesters.A wide range of structurally diverse asymmetrical aryl alkyl and dialkyl ketones have been constructed in yields of up to 98% with this strategy.The protocol has excellent reaction selectivity and functional group compatibility,representing a significant step forward in ketone synthesis.The one-pot decarboxylative acylation at the gram scale from two different carboxylic acids and the late-stage application for the synthesis of complex ketones shows its synthetic robustness.Both mechanistic experiments and density functional theory(DFT)calculations suggest that the decarboxylative acylation reaction operates via an underdeveloped Ni(Ⅰ)-Ni(Ⅱ)-Ni(Ⅰ)-Ni(Ⅲ)-Ni(Ⅰ)catalytic cycle.
文摘An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature.
文摘Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.
基金the National Key R&D Program of China(No.2022YFB4101900)National Natural Science Foundation of China(Nos.22278305,U21B2096)Natural Science Foundation of Tianjin City(No.23JCZDJC00040)。
文摘A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.
基金supported by the National Key R&D Program of China(No.2022YFC2105301)the National Natural Science Foundation of China(No.52270096).
文摘Microbial consortia that catalyze chain elongation processes have been enriched using different selection strategies,for which the electron donor is an essential one.Propanol is an extraordinarily promising electron donor because it can be generated from renewable resources,including lignocellulosic biomass and protein wastes.Here,propanol was proven in detail to be an efficient electron donor,enhancing the production of odd medium-chain carboxylates during chain elongation.By exploring various electron acceptors,reactor conditions,and electron donor/electron acceptor mol ratios,our study highlights that acetate is the most suitable electron acceptor for the production of both odd-and even-chain carboxylates.The optimal conditions for propanol-based chain elongation were 30℃ and pH 6,achieving 82.8%selectivity for odd-chain carboxylates.Another critical insight from our work is that a propanol/acetate mol ratio of 1:1 can minimize the inhibitory effect of propanol and maximize the yield of medium-chain carboxylates,with the highest concentration of n-heptanoate reaching 124.5 mmol C/L.This was further illustrated by 16S rRNA amplicon sequencing,which elucidated that the community composition and keystone species in a propanol-based reactor closely resembled that of the ethanol one.The dominant phylum of the propanol-based reactor,Firmicutes showed a significant positive correlation with the concentrations of n-caproate and n-valerate.Additionally,the co-occurrence of Clostridium sensu stricto 12 and Oscillibacter,known as typical chain elongators,was identified within the propanol-based reactor.These findings enhance our understanding of propanolbased chain elongation,offer guiding principles for reactor microbiota assembly,and support efficient odd medium-chain carboxylate production.
基金financial support from the National Natural Science Foundation of China(22408258 and 22378287)the Joint Founds of the National Natural Science Foundation of China(U20B6004)the Natural Science Foundation of Shanxi Province(202303021222012).
文摘Unconventional natural gas has become an important supplement to conventional energy sources,and the process of enrichment and purification of methane from low concentration coalbed methane is crucial.To this end,we report a copper-based metal-organic framework(MOF),ZJNU-119Cu,featuring two methane traps constructed with uncoordinated carboxylic acid oxygens and open metal sites.ZJNU-119Cu exhibits a high methane adsorption capacity(58.2 cm^(3)·g^(-1))at 298 K and 0.1 MPa and excellent CH_(4)/N_(2) separation performance under dynamic conditions.Densityfunctional theory calculations combined with grand canonical Monte Carlo simulation theory reveal the interaction mechanism for the uncoordinated carboxylic acid oxygen atoms and open metal sites in ZJNU-119Cu with CH4.The gas adsorption isotherms,heat of adsorption calculations,and breakthrough separation experiments indicate that this MOF is a very promising adsorbent for CH_(4)/N_(2) separation.