Polyhydroxyalkanoate(PHA),a well-known biodegradable polymer,featuresβ-lactones as its monomers,which can be selectively synthesized through ring-expansion carbonylation of epoxides using well-defined[Lewis acid]^(+)...Polyhydroxyalkanoate(PHA),a well-known biodegradable polymer,featuresβ-lactones as its monomers,which can be selectively synthesized through ring-expansion carbonylation of epoxides using well-defined[Lewis acid]^(+)[Co(CO)_(4)]^(-)catalysts.However,the decomposition of[Co(CO)_(4)]^(-)species at temperatures exceeding 80℃presents a hurdle for the development of commercially viable processes under high-temperature reaction conditions to reduce reaction time.Drawing insights from stable{(acyl)Co(CO)n}intermediates involved in historical HCo(CO)_(4)-catalyzed hydroformylation processes,we sought to the high-temperature catalytic activity of epoxide ring-expansion carbonylation.The developed catalyst system,[(acetyl)Co(CO)_(2)dppp]and[(TPP)CrCl],exhibited exceptional catalytic performance with an unprecedented initial turnover frequency of 4700 h^(-1)at 100℃and a turnover numbers of 93000.Notably,the catalyst displayed outstanding stability,operating at 80℃for 168 h while selectively generatingβ-lactones.展开更多
Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-c...Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-coupling reactions are among the most straightforward and effective methods for synthesizing chiral carbonyl compounds, including esters, amides, and ketones. The advances in asymmetric carbonylative cross-coupling reactions using various O-, N-, C-, and S-containing nucleophiles or electrophiles over the past decade are summarized.展开更多
The amide moiety plays an important role as a powerful bioactive backbone,and as the synthetic chemistry community moves toward more sp^(3)-rich scaffolds,alkyl halides have become the feedstock of choice for obtainin...The amide moiety plays an important role as a powerful bioactive backbone,and as the synthetic chemistry community moves toward more sp^(3)-rich scaffolds,alkyl halides have become the feedstock of choice for obtaining carbonylation products.With the development of photoredox catalysis,several aminocarbonylation systems for alkyl halides were developed which usually require transition metal catalysis.Considering the demands for green sustainable chemical synthesis,here we report a metal-free,exogenous catalyst-free aminocarbonylation reaction of alkyl iodides under atmospheric pressure of carbon monoxide.Through a combination of EDA and XAT strategies,the reaction occurs efficiently under only light irradiation at room temperature.展开更多
Carboxylic acid derivatives withα-quaternary carbon center are one of the most ubiquitous moieties in synthetic and medicinal chemistry.Hence,novel and efficient synthetic methods towards carboxylic acid derivatives ...Carboxylic acid derivatives withα-quaternary carbon center are one of the most ubiquitous moieties in synthetic and medicinal chemistry.Hence,novel and efficient synthetic methods towards carboxylic acid derivatives withα-quaternary carbon remain in high demand.However,most of the precursors of these complex compounds are not easy to prepare.Reported herein is a carbonylative five-component synthesis of amides and esters withα-quaternary carbon center enabled by palladium catalysis from abundant acrylonitrile,carbon monoxide,fluoroalkyl halides,and nucleophiles.Diverse amides and esters withα-quaternary carbon which contain difluoromethyl or perfluoroalkyl moiety were prepared in good to excellent yields,providing an efficient synthetic platform for sequential transformations.展开更多
Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in ...Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in moderate to excellent yields,and two promising luminescent material molecules have been synthesized using the developed method.The Lewis acid Fe Cl_(3)was introduced into this reaction,which effectively promoted the ring opening and rearrangement of cyclopropanes.This reaction features a broad substrate scope,satisfactory functional group tolerance,facile scalability,and easy derivatization of the products.展开更多
Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that sy...Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that synergizes CO_(2)-H_(2)O co-electrolysis(producing CO/O_(2) feeds)with oxidative double carbonylation of ethylene/acetylene to synthesize CO_(2)-derived C_(4) diesters(dimethyl succinate,fumarate,and maleate).A group of versatile building blocks for manufacturing plasticizers,biodegradable polymers,and pharmaceutical intermediates.Remarkably,CO_(2) exhibits dual functionality:serving simultaneously as a CO/O_(2) source and an explosion suppressant during the oxidative carbonylation process.We systematically investigated the explosion-suppressing efficacy of CO_(2) in flammable gas mixtures(CO/O_(2),C_(2)H_(4)/CO/O_(2),and C_(2)H_(2)/CO/O_(2))across varying concentrations.Notably,the mixed gas stream from CO_(2)/H_(2)O co-electrolysis at an industrial-scale current densities of 400 mA/cm^(2),enabling direct utilization in oxidative double carbonylation reactions with exceptional compatibility and inherent safety.Extended applications were demonstrated through substrate scope expansion and gram-scale synthesis.This study establishes not only a safe protocol for oxidative carbonylation processes,but also opens an innovative pathway for sustainable CO_(2) valorization,including CO surrogate and explosion suppressant.展开更多
Herein,we present a copper-catalyzed carbonylative cross-coupling of unactivated alkyl bromides with aryl boronates under CO atmosphere which enabling the efficient synthesis of C(sp3)-C(sp2)ketones with extensive fun...Herein,we present a copper-catalyzed carbonylative cross-coupling of unactivated alkyl bromides with aryl boronates under CO atmosphere which enabling the efficient synthesis of C(sp3)-C(sp2)ketones with extensive functional group compatibility.This strategy represents a significant advance in copper-catalyzed carbonylation involving alkyl bromides and C(sp2)-nucleophiles.The protocol addresses key challenges commonly encountered in the coupling of C(sp3)-alkyl halides with aryl boron reagents,such as sluggish oxidative addition of alkyl halides,competing Suzuki-Miyaura cross-coupling,undesired dehalogenation and so on.Distinguished by its broad substrate scope and high functional group tolerance,this approach offers a robust and versatile platform for the streamlined synthesis of alkyl aryl ketones.展开更多
Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Des...Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Despite continuous research efforts,the insight into the reaction mechanism and kinetics theory are still in their nascent stage.In this study,ZEO-1 material,a zeolite with up to now the largest cages comprising 16×16-MRs,16×12-MRs,and 12×12-MRs,was explored for DMM carbonylation and disproportionation reactions.The rate of MMAc formation based on accessible Brönsted acid sites is 2.5 times higher for ZEO-1(Si/Al=21)relative to the previously investigated FAU(Si/Al=15),indicating the positive effect of spatial separation of active sites in ZEO-1 on catalytic activity.A higher MF formation rate is also observed over ZEO-1 with lower activation energy(79.94 vs.95.19 kJ/mol)compared with FAU(Si/Al=30).Two types of active sites are proposed within ZEO-1 zeolite:Site 1 located in large cages formed by 16×16-MRs and 16×12-MRs,which is active predominantly for MMAc formation,and Site 2 located in smaller cages for methyl formate/dimethyl ether formation.Kinetics investigation of DMM carbonylation over ZEO-1 exhibit a first-order dependence on CO partial pressure and a slightly inverse-order dependence on DMM partial pressure.The DMM disproportionation is nearly first-order dependence on DMM partial pressure,while it reveals a strongly inverse dependence with increasing CO partial pressure.Furthermore,ZEO-1 exhibits good catalytic stability,and almost no deactivation is observed during the more than 70 h test with high carbonylation selectivity of above 89%,due to the well-enhanced diffusion property demonstrated by intelligent-gravimetric analysis.展开更多
Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In ...Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In this study,an anthropogenic COS emission inventory from 2015 to 2021 was constructed by applying the bottom-up approach based on activity data from emission sources.China’s anthropogenic COS emissions increased from approximately 171 to 198 Gg S yr^(-1)from 2015-2021,differing from the trends of other pollutants.Despite an initial decline in COS emissions across sectors during the early stage of the COVID-19 pandemic,a rapid rebound in emissions occurred following the resumption of economic activities.In 2021,industrial sources,coal combustion,agriculture and vehicle exhaust accounted for 76.8%,12.3%,10.5%and 0.4%of total COS emissions,respectively.The aluminum industry was the primary COS emitter among industrial sources,contributing40.7% of total emissions.Shandong,Shanxi,and Zhejiang were the top three provinces in terms of anthropogenic COS emissions,reaching 39,21 and 17 Gg S yr-1,respectively.Provincial-level regions(hereafter province)with high COS emissions are observed mainly in the eastern and coastal regions of China,which,together with the wind direction,helps explain the pattern of high COS concentrations in the Western Pacific Ocean in winter.The Green Contribution Coefficient of COS(GCCCOS)was used to assess the relationship between GDP and COS emissions,highlighting the disparity between GDP and COS contributions to green development.As part of this analysis,relevant recommendations are proposed to address this disparity.The COS emission inventory in our study can be used as input for the Sulfur Transport and Deposition Model(STEM),reducing uncertainties in the atmospheric COS source?sink budget and promoting understanding of the atmosphere sulfur cycle.展开更多
Matrix-assisted laser desorption/ionization(MALDI)mass spectrometry imaging(MSI)is an attractive technology for the visualization of metabolite distributions in tissues.However,detection and identification of low-abun...Matrix-assisted laser desorption/ionization(MALDI)mass spectrometry imaging(MSI)is an attractive technology for the visualization of metabolite distributions in tissues.However,detection and identification of low-abundance or poorly ionized metabolites remains challenging.Although on-tissue chemical derivatization(OTCD)holds great promise for improving MALDI MS detection sensitivity and selectivity by modification of specific chemical groups,the available methods for subsequent metabolite annotation are limited.Herein,a laser-assisted chemical transfer(LACT)-based parallel OTCD strategy was established for visualizing and annotating carbonyl metabolites in murine brain tissues.Girard's T and Girard's P reagents were applied for parallel OTCD to generate the characteristic m/z pairs with a 19.969 Da mass shift(±0.020 Da tolerance)for rapid recognition of derivatized metabolites.The similarity of spatial distribution patterns of each m/z pair was further statistically evaluated to remove the ambiguous annotations due to the occurrence of interference compounds.As a result,90 ion pairs were annotated as candidate carbonyl metabolites,66 were previously known and 24 were potential unreported carbonyls.Furthermore,the spatial alterations of carbonyl metabolites in the ischemic rat brain were successfully visualized and characterized,including small molecule aldehydes and ketones,long-chain fatty aldehydes,and monosaccharides.This further emphasizes great potential of parallel OTCD strategy for efficient and confident molecular annotation of spatial submetabolomics data associated with brain diseases.展开更多
Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8...Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8 assay. Apoptosis was measured using flow cytometry. Reagent kits were used to detect carbonyl stress markers malondialdehyde, 4-hydroxynonenal, thiobarbituric acid reactive substances, and protein carbonylation. Aldehyde-protein adduct formation and alcohol dehydrogenase, aldehyde dehydrogenase 2, aldo-keto reductase, nuclear factor E2-related factor 2(Nrf2), and cystathionine β-synthase(CBS) expression were determined using western blotting or real-time PCR. Sulforaphane(SFP) was used to activate Nrf2. RNA interference was used to inhibit CBS expression.Results GYY4137(an H_(2)S donor) pretreatment significantly reversed the uranium-induced increase in carbonyl stress markers and aldehyde-protein adducts. GYY4137 effectively restored the uraniumdecreased Nrf2 expression, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2, accompanied by a reversal of the uranium-decreased expression of CBS and aldehyde-metabolizing enzymes. The application of CBS siRNA efficiently abrogated the SFP-enhanced effects on the expression of CBS, Nrf2 activation, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2 and concomitantly reversed the SFP-enhanced effects of the uranium-induced mRNA expression of aldehyde-metabolizing enzymes.Simultaneously, CBS siRNA reversed the SFP-mediated alleviation of the uranium-induced increase in reactive aldehyde levels, apoptosis rates, and uranium-induced cell viability.Conclusion H_(2)S induces Nrf2 activation and nuclear translocation, which modulates the expression of aldehyde-metabolizing enzymes and the CBS/H_(2)S axis. Simultaneously, the Nrf2-controlled CBS/H_(2)S axis may at least partially promote Nrf2 activation and nuclear translocation. These events form a cycleregulating mode through which H_(2)S attenuates the carbonyl stress-mediated NRK-52E cytotoxicity triggered by uranium.展开更多
Marine biological activity has long been recognized to impact the atmospheric chemistry of coastal areas.In this work,we monitored the seasonal variation of carbonyl compounds in the coastal city of Qingdao,located in...Marine biological activity has long been recognized to impact the atmospheric chemistry of coastal areas.In this work,we monitored the seasonal variation of carbonyl compounds in the coastal city of Qingdao,located in the north of China’s coastline and the south of Jiaodong Peninsula,with the vast hinterland in the west.The mean total concentration of the 15 carbonyls varied significantly between seasons,with the highest observed in autumn(10.2±6.2 ppbv),followed by spring(9.0±3.0 ppbv),winter(6.4±4.0 ppbv)and summer(3.4±1.4 ppbv).Using bivariate analysis,the agricultural emissions from inland areas were responsible for the high levels of carbonyls in the autumn.In summer,clean and humid sea winds helped reduce the concentration of carbonyls,but they also brought air masses from vegetation,and marine organisms,which contributed to high levels of carbonyls in the spring of coastal areas.The observation-based chemistry box model found that the forma-tion of formaldehyde and acetaldehyde was primarily controlled by the RO+O2 reaction,and alkenes oxidation was the main contributing factor.Based on the OH radical loss rate(LOH)and ozone formation potential(OFP)calculation,we found that autumn and spring seasons have significantly higher values of LOH and OFP than winter and summer due to the presence of high concentrations of carbonyl compounds.Therefore,it is believed that these carbonyl compounds primarily originate from agricultural activities,and marine air influences the atmospheric chemistry of the coastal areas.展开更多
About 70%of the flue gas in the iron-steel industry has achieved multi-pollutant ultra-low emissions in China until 2023,and then the blast furnace gas purification has become the control step and bottleneck.Our resea...About 70%of the flue gas in the iron-steel industry has achieved multi-pollutant ultra-low emissions in China until 2023,and then the blast furnace gas purification has become the control step and bottleneck.Our research group has designed and constructed the world’s first blast furnace gas desulfurization pilot plant with the scale of 2000 Nm^(3)/h in October 2021.The pilot plant is a two-step combined desulfurization device including catalytic hydrolysis of carbonyl sulfur(COS)and absorption-oxidation of H_(2)S,continuously running for 120 days.In the hydrolysis system,one reason for catalyst deactivation has been verified from the sulfur deposition.HCN in blast furnace gas can be hydrolyzed on the hydrolysis catalyst to produce the nitrogen deposition,which is one of the reasons for catalyst deactivation and has never been found in previous studies.The deposition forms of S and N elements are determined,S element forms elemental sulfur and sulfate,while N element forms-NH_(2)and NH_(4)^(+).In the absorption-oxidation system,the O_(2)loading and the residence time have been optimized to control the oxidation of HS^(−)to produce elemental sulfur instead of by-product S_(2)O_(3)^(2−).The balance and distribution of S and N elements have been calculated for thewholemulti-phase system,approximately 84.4%of the sulfur is converted to solid sulfur product,about 1.3%of the sulfur and 19.2%of N element are deposited on the hydrolysis catalyst.The pilot plant provides technical support formulti-pollutant control of blast furnace.展开更多
The advancement of wireless technologies has increased the global demand for ubiquitous connectivity.However,this surge has increased electromagnetic pollution.This study introduces a composite comprising a polymer ma...The advancement of wireless technologies has increased the global demand for ubiquitous connectivity.However,this surge has increased electromagnetic pollution.This study introduces a composite comprising a polymer matrix(polydimethylsiloxane,PDMS)and a magnetic filler(carbonyl iron powder,CIP)to effectively absorb electromagnetic waves(EMW)and suppress electromagnetic noise,while exhibiting good mechanical properties.Eutectic gallium–indium(EGa In)liquid metal(LM)was introduced to improve the insulating properties of magnetic fillers.A core–shell structure was obtained by coating the CIP particles with EGa In,thereby combining magnetic and dielectric materials to enhance EMW absorption.The fluid characteristics of the LM improved the mechanical properties,whereas its electrical conductivity enhanced interfacial polarization loss,thereby augmenting the dielectric loss value of the composites.Moreover,the application of mechanical strain enhanced the EMW absorption of the LM/CIP/PDMS composites due to the formation of a conductive LM network.展开更多
Oxidative carbonylation of ethanol to diethyl carbonate(DEC),an essential electrolyte for lithium-ion battery,has attracted broad interest from both academia and industry in recent years.But high selective formation o...Oxidative carbonylation of ethanol to diethyl carbonate(DEC),an essential electrolyte for lithium-ion battery,has attracted broad interest from both academia and industry in recent years.But high selective formation of DEC is a great challenge due to the difficultyin efficientactivation of CO at the same time as the site-specificactivation of O―H bond in ethanol.Herein,we propose a Pd-Cu_(x)O synergetic catalysis toward oxidative carbonylation of ethanol,where the synergy between Pd and Cu_(x)O promotes CO activation and carbonylation,thus increasing the selectivity to the site-specificactivation of O―H bond in ethanol.A nitrogen-doped carbon nanotubes supported Pd-Cu_(x)O(Pd-Cu_(x)O/NCNTs)has been designed via galvanic displacement of Pd on Cu_(x)O to form the strong interactions between Pd and Cu_(x)O,affording a selectivity of 94.7%to DEC and a space-time yield(STY)of up to 5966 mg·g^(-1)·h^(-1),which is an order of magnitude higher than that reported in the literatures.This work offers novel insights for the design of highly efficientcatalysts and advances the industrial development for the oxidative carbonylation of ethanol.展开更多
In the field of broadband metamaterial absorbers,most research efforts have focused on optimizing the resonant layers and designing multi-layer structures,but relatively little attention has been paid to the dielectri...In the field of broadband metamaterial absorbers,most research efforts have focused on optimizing the resonant layers and designing multi-layer structures,but relatively little attention has been paid to the dielectric layers themselves.This paper proposed a method using carbonyl iron powder to modify the dielectric layer.This method significantly enhances the electromagnetic wave attenuation capability of the dielectric layer with the X-band range for metamaterial absorbers.A broadband absorber with a reflection loss(RL)of less than-10 dB within the frequency range of 4.98-18 GHz and covering the C,X,and Ku band was designed.This work analyzed the surface current distribution and the power loss distribution to elucidate the absorption mechanism of the absorber.It was found that the modified dielectric layer accounted for more than 30%of the total loss in the 2-18 GHz frequency band,and the effective absorption bandwidth(RL≤-10 dB)was almost twice that of the unmodified dielectric layer.This enhancement in absorption bandwidth is attributed to the introduction of a new electromagnetic wave loss mechanism by carbonyl iron powder.Meanwhile,the absorber exhibited good angular stability,maintaining at least 80%absorption(RL≤-7 dB)in the 7.0-18.0 GHz range even when the incident angle was increased to 60°.The experimental results showed that the measured results matched the simulation results well.Furthermore,compared with other methods for broadening the absorption bandwidth,the metamaterial absorber obtained by this method offers several advantages,including wideband absorption,thin profile,and a simple manufacturing process.This approach provides a new and promising direction for the design of broadband absorbers.展开更多
Carbonyl compounds are abundant in nature and represent a substantial portion of biomass resources.Despite significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo...Carbonyl compounds are abundant in nature and represent a substantial portion of biomass resources.Despite significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate challenge.Herein,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single step.This method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material sciences.Mechanistic investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.展开更多
With global carbon emissions continuing to rise,carbon dioxide(CO_(2))capture and resource utilization have become central challenges in achieving the“dual carbon”goals(carbon peak and carbon neutrality).Traditional...With global carbon emissions continuing to rise,carbon dioxide(CO_(2))capture and resource utilization have become central challenges in achieving the“dual carbon”goals(carbon peak and carbon neutrality).Traditional carbon capture and storage(CCS)technology can only temporarily sequester CO_(2),whereas emerging green catalytic technologies(photo/electro/thermal catalysis)enable the conversion of CO_(2) into high-value chemicals(e.g.,fuels,pharmaceutical intermediates),advancing the closure of the artificial carbon cycle[1,2].展开更多
Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper （Cu/HMOR） catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wet...Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper （Cu/HMOR） catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wetness impregnation and ion-exchange. The results showed that Cu/HMOR prepared via iron-exchange method exhibited the highest catalytic activity due to the synergistic effect of active-site metal and acidic molecular sieve support. Conversion of 95.3% and methyl acetate selectivity of 94.9% were achieved under conditions of 210℃, 1.5 MPa, and GSHV of 4883 h-1. The catalysts were characterized by nitrogen absorption, X-ray diffraction, NH3 temperature program desorption, and CO temperature program desorption techniques. It was found that Cu/HMOR prepared by ion-exchange method possessed high surface area, moderate strong acid centers, and CO adsorption centers, which improved catalytic performance for the reaction of CO insertion to dimethyl ether.展开更多
The effect of calcination temperature on the catalytic activity for the dimethyl ether （DME） carbonylation into methyl acetate （MA） was investigated over mordenite supported copper （Cu/HMOR） prepared by ion-exch...The effect of calcination temperature on the catalytic activity for the dimethyl ether （DME） carbonylation into methyl acetate （MA） was investigated over mordenite supported copper （Cu/HMOR） prepared by ion-exchange process. The results showed that the catalytic activity was obviously affected by the calcination temperature. The maximal DME conversion of 97.2% and the MA selectivity of 97.9% were obtained over the Cu/HMOR calcined at 430 ℃ under conditions of 210 ℃, 1.5 MPa, and GSHV of 4883 h^-1. The obtained Cu/HMOR catalysts were characterized by powder X-ray diffraction, N2 absorption, NH3 temperature program desorption, CO temperature program desorption, and Raman techniques. Proper calcination temperature was effective to promote copper ions migration and diffusion, and led the support HMOR to possess more acid activity sites, which exhibited the complete decomposing of copper nitrate, large surface area and optimum micropore structure, more amount of CO adsorption site and proper amount of weak acid centers.展开更多
文摘Polyhydroxyalkanoate(PHA),a well-known biodegradable polymer,featuresβ-lactones as its monomers,which can be selectively synthesized through ring-expansion carbonylation of epoxides using well-defined[Lewis acid]^(+)[Co(CO)_(4)]^(-)catalysts.However,the decomposition of[Co(CO)_(4)]^(-)species at temperatures exceeding 80℃presents a hurdle for the development of commercially viable processes under high-temperature reaction conditions to reduce reaction time.Drawing insights from stable{(acyl)Co(CO)n}intermediates involved in historical HCo(CO)_(4)-catalyzed hydroformylation processes,we sought to the high-temperature catalytic activity of epoxide ring-expansion carbonylation.The developed catalyst system,[(acetyl)Co(CO)_(2)dppp]and[(TPP)CrCl],exhibited exceptional catalytic performance with an unprecedented initial turnover frequency of 4700 h^(-1)at 100℃and a turnover numbers of 93000.Notably,the catalyst displayed outstanding stability,operating at 80℃for 168 h while selectively generatingβ-lactones.
文摘Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-coupling reactions are among the most straightforward and effective methods for synthesizing chiral carbonyl compounds, including esters, amides, and ketones. The advances in asymmetric carbonylative cross-coupling reactions using various O-, N-, C-, and S-containing nucleophiles or electrophiles over the past decade are summarized.
基金supported by National Key R&D Program of China(No.2023YFA1507500)the International Partnership Program of Chinese Academy of Sciences(No.028GJHZ2023045FN)。
文摘The amide moiety plays an important role as a powerful bioactive backbone,and as the synthetic chemistry community moves toward more sp^(3)-rich scaffolds,alkyl halides have become the feedstock of choice for obtaining carbonylation products.With the development of photoredox catalysis,several aminocarbonylation systems for alkyl halides were developed which usually require transition metal catalysis.Considering the demands for green sustainable chemical synthesis,here we report a metal-free,exogenous catalyst-free aminocarbonylation reaction of alkyl iodides under atmospheric pressure of carbon monoxide.Through a combination of EDA and XAT strategies,the reaction occurs efficiently under only light irradiation at room temperature.
基金the financial support from National Key R&D Program of China(No.2023YFA1507500)DICP。
文摘Carboxylic acid derivatives withα-quaternary carbon center are one of the most ubiquitous moieties in synthetic and medicinal chemistry.Hence,novel and efficient synthetic methods towards carboxylic acid derivatives withα-quaternary carbon remain in high demand.However,most of the precursors of these complex compounds are not easy to prepare.Reported herein is a carbonylative five-component synthesis of amides and esters withα-quaternary carbon center enabled by palladium catalysis from abundant acrylonitrile,carbon monoxide,fluoroalkyl halides,and nucleophiles.Diverse amides and esters withα-quaternary carbon which contain difluoromethyl or perfluoroalkyl moiety were prepared in good to excellent yields,providing an efficient synthetic platform for sequential transformations.
基金the financial support from the National Natural Science Foundation of China(Nos.21801025,22225106)Natural Science Foundation of Sichuan Province(No.2022NSFSC0200)Sichuan Science and Technology Program(No.MZGC20230100)。
文摘Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in moderate to excellent yields,and two promising luminescent material molecules have been synthesized using the developed method.The Lewis acid Fe Cl_(3)was introduced into this reaction,which effectively promoted the ring opening and rearrangement of cyclopropanes.This reaction features a broad substrate scope,satisfactory functional group tolerance,facile scalability,and easy derivatization of the products.
文摘Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that synergizes CO_(2)-H_(2)O co-electrolysis(producing CO/O_(2) feeds)with oxidative double carbonylation of ethylene/acetylene to synthesize CO_(2)-derived C_(4) diesters(dimethyl succinate,fumarate,and maleate).A group of versatile building blocks for manufacturing plasticizers,biodegradable polymers,and pharmaceutical intermediates.Remarkably,CO_(2) exhibits dual functionality:serving simultaneously as a CO/O_(2) source and an explosion suppressant during the oxidative carbonylation process.We systematically investigated the explosion-suppressing efficacy of CO_(2) in flammable gas mixtures(CO/O_(2),C_(2)H_(4)/CO/O_(2),and C_(2)H_(2)/CO/O_(2))across varying concentrations.Notably,the mixed gas stream from CO_(2)/H_(2)O co-electrolysis at an industrial-scale current densities of 400 mA/cm^(2),enabling direct utilization in oxidative double carbonylation reactions with exceptional compatibility and inherent safety.Extended applications were demonstrated through substrate scope expansion and gram-scale synthesis.This study establishes not only a safe protocol for oxidative carbonylation processes,but also opens an innovative pathway for sustainable CO_(2) valorization,including CO surrogate and explosion suppressant.
文摘Herein,we present a copper-catalyzed carbonylative cross-coupling of unactivated alkyl bromides with aryl boronates under CO atmosphere which enabling the efficient synthesis of C(sp3)-C(sp2)ketones with extensive functional group compatibility.This strategy represents a significant advance in copper-catalyzed carbonylation involving alkyl bromides and C(sp2)-nucleophiles.The protocol addresses key challenges commonly encountered in the coupling of C(sp3)-alkyl halides with aryl boron reagents,such as sluggish oxidative addition of alkyl halides,competing Suzuki-Miyaura cross-coupling,undesired dehalogenation and so on.Distinguished by its broad substrate scope and high functional group tolerance,this approach offers a robust and versatile platform for the streamlined synthesis of alkyl aryl ketones.
文摘Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Despite continuous research efforts,the insight into the reaction mechanism and kinetics theory are still in their nascent stage.In this study,ZEO-1 material,a zeolite with up to now the largest cages comprising 16×16-MRs,16×12-MRs,and 12×12-MRs,was explored for DMM carbonylation and disproportionation reactions.The rate of MMAc formation based on accessible Brönsted acid sites is 2.5 times higher for ZEO-1(Si/Al=21)relative to the previously investigated FAU(Si/Al=15),indicating the positive effect of spatial separation of active sites in ZEO-1 on catalytic activity.A higher MF formation rate is also observed over ZEO-1 with lower activation energy(79.94 vs.95.19 kJ/mol)compared with FAU(Si/Al=30).Two types of active sites are proposed within ZEO-1 zeolite:Site 1 located in large cages formed by 16×16-MRs and 16×12-MRs,which is active predominantly for MMAc formation,and Site 2 located in smaller cages for methyl formate/dimethyl ether formation.Kinetics investigation of DMM carbonylation over ZEO-1 exhibit a first-order dependence on CO partial pressure and a slightly inverse-order dependence on DMM partial pressure.The DMM disproportionation is nearly first-order dependence on DMM partial pressure,while it reveals a strongly inverse dependence with increasing CO partial pressure.Furthermore,ZEO-1 exhibits good catalytic stability,and almost no deactivation is observed during the more than 70 h test with high carbonylation selectivity of above 89%,due to the well-enhanced diffusion property demonstrated by intelligent-gravimetric analysis.
基金National Natural Science Foundation of China,No.42250205“CUG Scholar”Scientific Research Funds at China University of Geosciences,No.2019004+1 种基金Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA23100202Scientific Research Foundation of China University of Geosciences,No.162301192642。
文摘Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In this study,an anthropogenic COS emission inventory from 2015 to 2021 was constructed by applying the bottom-up approach based on activity data from emission sources.China’s anthropogenic COS emissions increased from approximately 171 to 198 Gg S yr^(-1)from 2015-2021,differing from the trends of other pollutants.Despite an initial decline in COS emissions across sectors during the early stage of the COVID-19 pandemic,a rapid rebound in emissions occurred following the resumption of economic activities.In 2021,industrial sources,coal combustion,agriculture and vehicle exhaust accounted for 76.8%,12.3%,10.5%and 0.4%of total COS emissions,respectively.The aluminum industry was the primary COS emitter among industrial sources,contributing40.7% of total emissions.Shandong,Shanxi,and Zhejiang were the top three provinces in terms of anthropogenic COS emissions,reaching 39,21 and 17 Gg S yr-1,respectively.Provincial-level regions(hereafter province)with high COS emissions are observed mainly in the eastern and coastal regions of China,which,together with the wind direction,helps explain the pattern of high COS concentrations in the Western Pacific Ocean in winter.The Green Contribution Coefficient of COS(GCCCOS)was used to assess the relationship between GDP and COS emissions,highlighting the disparity between GDP and COS contributions to green development.As part of this analysis,relevant recommendations are proposed to address this disparity.The COS emission inventory in our study can be used as input for the Sulfur Transport and Deposition Model(STEM),reducing uncertainties in the atmospheric COS source?sink budget and promoting understanding of the atmosphere sulfur cycle.
基金supported by the National Natural Science Foundation of China(Nos.82374028 and 81803957)。
文摘Matrix-assisted laser desorption/ionization(MALDI)mass spectrometry imaging(MSI)is an attractive technology for the visualization of metabolite distributions in tissues.However,detection and identification of low-abundance or poorly ionized metabolites remains challenging.Although on-tissue chemical derivatization(OTCD)holds great promise for improving MALDI MS detection sensitivity and selectivity by modification of specific chemical groups,the available methods for subsequent metabolite annotation are limited.Herein,a laser-assisted chemical transfer(LACT)-based parallel OTCD strategy was established for visualizing and annotating carbonyl metabolites in murine brain tissues.Girard's T and Girard's P reagents were applied for parallel OTCD to generate the characteristic m/z pairs with a 19.969 Da mass shift(±0.020 Da tolerance)for rapid recognition of derivatized metabolites.The similarity of spatial distribution patterns of each m/z pair was further statistically evaluated to remove the ambiguous annotations due to the occurrence of interference compounds.As a result,90 ion pairs were annotated as candidate carbonyl metabolites,66 were previously known and 24 were potential unreported carbonyls.Furthermore,the spatial alterations of carbonyl metabolites in the ischemic rat brain were successfully visualized and characterized,including small molecule aldehydes and ketones,long-chain fatty aldehydes,and monosaccharides.This further emphasizes great potential of parallel OTCD strategy for efficient and confident molecular annotation of spatial submetabolomics data associated with brain diseases.
基金supported by the National Natural Science Foundation of China(No.82160627)the Natural Science Foundation of the Guangxi Autonomous Region(No.2020GXNFSAA297262)。
文摘Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8 assay. Apoptosis was measured using flow cytometry. Reagent kits were used to detect carbonyl stress markers malondialdehyde, 4-hydroxynonenal, thiobarbituric acid reactive substances, and protein carbonylation. Aldehyde-protein adduct formation and alcohol dehydrogenase, aldehyde dehydrogenase 2, aldo-keto reductase, nuclear factor E2-related factor 2(Nrf2), and cystathionine β-synthase(CBS) expression were determined using western blotting or real-time PCR. Sulforaphane(SFP) was used to activate Nrf2. RNA interference was used to inhibit CBS expression.Results GYY4137(an H_(2)S donor) pretreatment significantly reversed the uranium-induced increase in carbonyl stress markers and aldehyde-protein adducts. GYY4137 effectively restored the uraniumdecreased Nrf2 expression, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2, accompanied by a reversal of the uranium-decreased expression of CBS and aldehyde-metabolizing enzymes. The application of CBS siRNA efficiently abrogated the SFP-enhanced effects on the expression of CBS, Nrf2 activation, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2 and concomitantly reversed the SFP-enhanced effects of the uranium-induced mRNA expression of aldehyde-metabolizing enzymes.Simultaneously, CBS siRNA reversed the SFP-mediated alleviation of the uranium-induced increase in reactive aldehyde levels, apoptosis rates, and uranium-induced cell viability.Conclusion H_(2)S induces Nrf2 activation and nuclear translocation, which modulates the expression of aldehyde-metabolizing enzymes and the CBS/H_(2)S axis. Simultaneously, the Nrf2-controlled CBS/H_(2)S axis may at least partially promote Nrf2 activation and nuclear translocation. These events form a cycleregulating mode through which H_(2)S attenuates the carbonyl stress-mediated NRK-52E cytotoxicity triggered by uranium.
基金supported by the National Natural Science Foundation of China(Nos.21976106,42005092,and 42105111)the Natural Science Foundation of Shandong Province(Nos.ZR2020QD058 and ZR2021QD144)+1 种基金the Introduction and Cultivation Plan for Young Innovative Talents of Colleges and Universities by the Education Department of Shandong Province(No.142,2019)。
文摘Marine biological activity has long been recognized to impact the atmospheric chemistry of coastal areas.In this work,we monitored the seasonal variation of carbonyl compounds in the coastal city of Qingdao,located in the north of China’s coastline and the south of Jiaodong Peninsula,with the vast hinterland in the west.The mean total concentration of the 15 carbonyls varied significantly between seasons,with the highest observed in autumn(10.2±6.2 ppbv),followed by spring(9.0±3.0 ppbv),winter(6.4±4.0 ppbv)and summer(3.4±1.4 ppbv).Using bivariate analysis,the agricultural emissions from inland areas were responsible for the high levels of carbonyls in the autumn.In summer,clean and humid sea winds helped reduce the concentration of carbonyls,but they also brought air masses from vegetation,and marine organisms,which contributed to high levels of carbonyls in the spring of coastal areas.The observation-based chemistry box model found that the forma-tion of formaldehyde and acetaldehyde was primarily controlled by the RO+O2 reaction,and alkenes oxidation was the main contributing factor.Based on the OH radical loss rate(LOH)and ozone formation potential(OFP)calculation,we found that autumn and spring seasons have significantly higher values of LOH and OFP than winter and summer due to the presence of high concentrations of carbonyl compounds.Therefore,it is believed that these carbonyl compounds primarily originate from agricultural activities,and marine air influences the atmospheric chemistry of the coastal areas.
基金supported by the Key Research and Development Program of Hebei Province(No.21373702D)the Key Science and Technology Program of HBIS Group Co.,Ltd.(No.HG2021117)+1 种基金the National Natural Science Foundation of China(No.52370124)the National Key R&D Program of China(No.2023YFC3707003).
文摘About 70%of the flue gas in the iron-steel industry has achieved multi-pollutant ultra-low emissions in China until 2023,and then the blast furnace gas purification has become the control step and bottleneck.Our research group has designed and constructed the world’s first blast furnace gas desulfurization pilot plant with the scale of 2000 Nm^(3)/h in October 2021.The pilot plant is a two-step combined desulfurization device including catalytic hydrolysis of carbonyl sulfur(COS)and absorption-oxidation of H_(2)S,continuously running for 120 days.In the hydrolysis system,one reason for catalyst deactivation has been verified from the sulfur deposition.HCN in blast furnace gas can be hydrolyzed on the hydrolysis catalyst to produce the nitrogen deposition,which is one of the reasons for catalyst deactivation and has never been found in previous studies.The deposition forms of S and N elements are determined,S element forms elemental sulfur and sulfate,while N element forms-NH_(2)and NH_(4)^(+).In the absorption-oxidation system,the O_(2)loading and the residence time have been optimized to control the oxidation of HS^(−)to produce elemental sulfur instead of by-product S_(2)O_(3)^(2−).The balance and distribution of S and N elements have been calculated for thewholemulti-phase system,approximately 84.4%of the sulfur is converted to solid sulfur product,about 1.3%of the sulfur and 19.2%of N element are deposited on the hydrolysis catalyst.The pilot plant provides technical support formulti-pollutant control of blast furnace.
基金supported by the Global Research Development Center(GRDC)Cooperative Hub Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(MSIT)(No.RS-202300257595)。
文摘The advancement of wireless technologies has increased the global demand for ubiquitous connectivity.However,this surge has increased electromagnetic pollution.This study introduces a composite comprising a polymer matrix(polydimethylsiloxane,PDMS)and a magnetic filler(carbonyl iron powder,CIP)to effectively absorb electromagnetic waves(EMW)and suppress electromagnetic noise,while exhibiting good mechanical properties.Eutectic gallium–indium(EGa In)liquid metal(LM)was introduced to improve the insulating properties of magnetic fillers.A core–shell structure was obtained by coating the CIP particles with EGa In,thereby combining magnetic and dielectric materials to enhance EMW absorption.The fluid characteristics of the LM improved the mechanical properties,whereas its electrical conductivity enhanced interfacial polarization loss,thereby augmenting the dielectric loss value of the composites.Moreover,the application of mechanical strain enhanced the EMW absorption of the LM/CIP/PDMS composites due to the formation of a conductive LM network.
基金Financial support from the National Natural Science Foundation of China(22138001 and 22288102)。
文摘Oxidative carbonylation of ethanol to diethyl carbonate(DEC),an essential electrolyte for lithium-ion battery,has attracted broad interest from both academia and industry in recent years.But high selective formation of DEC is a great challenge due to the difficultyin efficientactivation of CO at the same time as the site-specificactivation of O―H bond in ethanol.Herein,we propose a Pd-Cu_(x)O synergetic catalysis toward oxidative carbonylation of ethanol,where the synergy between Pd and Cu_(x)O promotes CO activation and carbonylation,thus increasing the selectivity to the site-specificactivation of O―H bond in ethanol.A nitrogen-doped carbon nanotubes supported Pd-Cu_(x)O(Pd-Cu_(x)O/NCNTs)has been designed via galvanic displacement of Pd on Cu_(x)O to form the strong interactions between Pd and Cu_(x)O,affording a selectivity of 94.7%to DEC and a space-time yield(STY)of up to 5966 mg·g^(-1)·h^(-1),which is an order of magnitude higher than that reported in the literatures.This work offers novel insights for the design of highly efficientcatalysts and advances the industrial development for the oxidative carbonylation of ethanol.
基金supported by the Key Research and Development Projects of Shaanxi Province,China(No.2020 ZDGY01-01)the Fundamental Research Funds for the Central Universities,China(No.D5000220202).
文摘In the field of broadband metamaterial absorbers,most research efforts have focused on optimizing the resonant layers and designing multi-layer structures,but relatively little attention has been paid to the dielectric layers themselves.This paper proposed a method using carbonyl iron powder to modify the dielectric layer.This method significantly enhances the electromagnetic wave attenuation capability of the dielectric layer with the X-band range for metamaterial absorbers.A broadband absorber with a reflection loss(RL)of less than-10 dB within the frequency range of 4.98-18 GHz and covering the C,X,and Ku band was designed.This work analyzed the surface current distribution and the power loss distribution to elucidate the absorption mechanism of the absorber.It was found that the modified dielectric layer accounted for more than 30%of the total loss in the 2-18 GHz frequency band,and the effective absorption bandwidth(RL≤-10 dB)was almost twice that of the unmodified dielectric layer.This enhancement in absorption bandwidth is attributed to the introduction of a new electromagnetic wave loss mechanism by carbonyl iron powder.Meanwhile,the absorber exhibited good angular stability,maintaining at least 80%absorption(RL≤-7 dB)in the 7.0-18.0 GHz range even when the incident angle was increased to 60°.The experimental results showed that the measured results matched the simulation results well.Furthermore,compared with other methods for broadening the absorption bandwidth,the metamaterial absorber obtained by this method offers several advantages,including wideband absorption,thin profile,and a simple manufacturing process.This approach provides a new and promising direction for the design of broadband absorbers.
基金National Natural Science Foundation of China(NSFC,No.21971093)the Fundamental Research Funds for the Central Universities(No.lzujbky-2021-sp53)+2 种基金the International Joint Research centre for Green Catalysis and Synthesis(No.2016B01017)The Science and Technology Major Program of Gansu Province of China(No.22ZD6FA006)the 111 project for support of our research.We also thank the Canada Research Chair(Tier I)foundation,the E.B。
文摘Carbonyl compounds are abundant in nature and represent a substantial portion of biomass resources.Despite significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate challenge.Herein,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single step.This method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material sciences.Mechanistic investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.
基金supported by the National Natural Science Foundation of China(22472069,22102064,and 22302080)China Postdoctoral Science Foundation(2024M760028).
文摘With global carbon emissions continuing to rise,carbon dioxide(CO_(2))capture and resource utilization have become central challenges in achieving the“dual carbon”goals(carbon peak and carbon neutrality).Traditional carbon capture and storage(CCS)technology can only temporarily sequester CO_(2),whereas emerging green catalytic technologies(photo/electro/thermal catalysis)enable the conversion of CO_(2) into high-value chemicals(e.g.,fuels,pharmaceutical intermediates),advancing the closure of the artificial carbon cycle[1,2].
文摘Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper （Cu/HMOR） catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wetness impregnation and ion-exchange. The results showed that Cu/HMOR prepared via iron-exchange method exhibited the highest catalytic activity due to the synergistic effect of active-site metal and acidic molecular sieve support. Conversion of 95.3% and methyl acetate selectivity of 94.9% were achieved under conditions of 210℃, 1.5 MPa, and GSHV of 4883 h-1. The catalysts were characterized by nitrogen absorption, X-ray diffraction, NH3 temperature program desorption, and CO temperature program desorption techniques. It was found that Cu/HMOR prepared by ion-exchange method possessed high surface area, moderate strong acid centers, and CO adsorption centers, which improved catalytic performance for the reaction of CO insertion to dimethyl ether.
基金This work was supported by the National Natural Science Foundation of China （No.51006110 and No.51276183） and the National Natural Research Foundation of China/Japan Science and Technology Agency （No.51161140331）.
文摘The effect of calcination temperature on the catalytic activity for the dimethyl ether （DME） carbonylation into methyl acetate （MA） was investigated over mordenite supported copper （Cu/HMOR） prepared by ion-exchange process. The results showed that the catalytic activity was obviously affected by the calcination temperature. The maximal DME conversion of 97.2% and the MA selectivity of 97.9% were obtained over the Cu/HMOR calcined at 430 ℃ under conditions of 210 ℃, 1.5 MPa, and GSHV of 4883 h^-1. The obtained Cu/HMOR catalysts were characterized by powder X-ray diffraction, N2 absorption, NH3 temperature program desorption, CO temperature program desorption, and Raman techniques. Proper calcination temperature was effective to promote copper ions migration and diffusion, and led the support HMOR to possess more acid activity sites, which exhibited the complete decomposing of copper nitrate, large surface area and optimum micropore structure, more amount of CO adsorption site and proper amount of weak acid centers.
