Catalyst-aided regeneration is a promising method for reducing the high regeneration energy consumption of amine-based CO_(2)capture technologies.However,the intrinsic relationship between the properties of the acidic...Catalyst-aided regeneration is a promising method for reducing the high regeneration energy consumption of amine-based CO_(2)capture technologies.However,the intrinsic relationship between the properties of the acidic sites and their catalytic activity is controversial.In this study,a series of W-based catalysts supported by ZrTiO_(x)were synthesised,and the effects of the intensity,distribution,and type of acid sites were systematically investigated by quantitatively regulating the acidic site properties.The results indicate stronger acidic sites play a more important role in the catalytic reaction.Moreover,the catalysts showed excellent performance only if the Br?nsted acid sites(BASs)and Lewis acid sites(LASs)coexisted.During the catalytic reaction,the BASs facilitated deprotonation,and the LASs promoted the decomposition of carbamates.The ratio of BASs to LASs(B/L)was a critical factor for catalytic activity,wherein optimal performance was achieved when the B/L ratio was close to 1.The 10%HPW/ZrTiO_(x)composite performed better than WO_(3)/ZrTiO_(x)and HSiW/ZrTiO_(x)because it had a stronger acid intensity and a suitable B/L ratio.As a result,the relative heat duty was reduced by 47%compared to 30%aqueous MEA,and the maximum CO_(2)desorption rate was increased by 83%.The Bader charge indicated that the W atoms of HPW/ZrTiO_(x)lost more electrons(0.18)than those of WO_(3)/ZrTiO_(x),which can weaken the O±H bond energy.Consequently,the calculated deprotonation energy is as low as 257 kJ mol^(-1)for HPW/ZrTiO_(x).展开更多
Amines represent fundamental motifs in various chemical contexts and are widely used in agrochemicals and pharmaceuticals.The development of earth-abundant metal-based heterogeneous catalysts for the synthesis amines ...Amines represent fundamental motifs in various chemical contexts and are widely used in agrochemicals and pharmaceuticals.The development of earth-abundant metal-based heterogeneous catalysts for the synthesis amines remains an important goal in terms of chemical research and industrial application/manufacture.Herein,we developed an efficient and highly selective nitrogen-doped nickel catalyst enriched with Lewis acid sites,which has been applied for to the hydrogenative coupling of nitriles and amines with molecular hydrogen for the synthesis of a train of functionalised and structurally diverse secondary and tertiary amines.Furthermore,catalytic hydrogenation and deuteration of nitriles were achieved under milder conditions,yielding a series of primary amines and deuterated amines with high deuterium incorporation.展开更多
[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was synthesized,using tert-butyldimethylsilane(TBDMS)and 1,2-epoxy-4-vinylcyclohexane(EVC)as the main raw materials and tris(triphenylphosphine)chlororhodium(I)[...[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was synthesized,using tert-butyldimethylsilane(TBDMS)and 1,2-epoxy-4-vinylcyclohexane(EVC)as the main raw materials and tris(triphenylphosphine)chlororhodium(I)[RhCl(Ph3P)3]as the catalyst.[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane is a novel kind of silicon-containing epoxide.The factors affecting the reaction yield,such as catalyst use,reaction time and reaction temperature,were investigated,and the synthesized product was characterized and analyzed by FT-IR and 1H-NMR.A series of amine-curing resins were prepared with[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane,bisphenol A epoxy resin(E-51)and modified amine(593 amine).The mechanical properties of cured splines with the different proportions of amine-curing resins were tested.When the content of 593 amine was 20%,the content of E-51 was 75%and the amount of[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was 5%,the mechanical properties of the cured splines were the best with the tensile strength being 23.3 MPa,the elongation at break being 7.8%,and the Young's modulus being 421.3 MPa.展开更多
A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the ...A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the reaction step and atom economy. It has been investigated that the 2,4,6-trimethylpyridine ligand was critical to achieve the optimized reactivity. This protocol provides a straightforward route for synthesizing the alkynylated free benzylamines, featuring good substrate compatibility and monoselectivity.展开更多
The biphasic solvent is a promising solution to reduce regeneration energy consumption in CO_(2) capture.However,most current biphasic solvents suffer from high viscosity and poor desorption of the rich phase.To the i...The biphasic solvent is a promising solution to reduce regeneration energy consumption in CO_(2) capture.However,most current biphasic solvents suffer from high viscosity and poor desorption of the rich phase.To the issues,a novel pentamethyldiethylenetriamine(PMDETA)-2-amino-2-methyl-1-propanol(AMP)/diethylenetriamine(DETA)-sulfolane biphasic solvent was developed.The mechanism of AMP affecting CO_(2) recycling capacity was analyzed.By adjusting the ratio of AMP and DETA,the absorption and desorption performance were balanced,and the recycling capacity and renewable energy consumption of the absorbent were improved.For the P_(2.4)A_(0.8)D_(0.8)S_(2) biphasic solvent,the CO_(2) loading of the rich phase was 5.87 mol/L,and the proportion of the rich phase volume ratio was 35%,which surpasses most reported biphasic solvents.The viscosity of the absorbent significantly decreased from 527.00 mPa·s to 92.26 mPa·s,attributed to the beneficial effect of AMP.Thermodynamic analysis showed that the biphasic solvent produced a lower regeneration energy consumption of 1.70 GJ/t CO_(2),which was 57%lower than that of monoethanolamine(MEA).Overall,the PMDETA-AMP/DETA-sulfolane biphasic solvent exhibited cycle capacity,which provided new insights for the designing of biphasic solvent.展开更多
In-depth knowledge of the microbes responsible for biogenic amine(BA)production during soy sauce fermentation remains limited.Herein,the variations in the BA profiles,microbial communities,and microbes involved in BA ...In-depth knowledge of the microbes responsible for biogenic amine(BA)production during soy sauce fermentation remains limited.Herein,the variations in the BA profiles,microbial communities,and microbes involved in BA production during the fermentation of soy sauce through Japanese-type(JP)and Cantonese-type(CP)processes were compared.BA analysis revealed that the most abundant BA species were putrescine,tyramine,and histamine in the later three stages(1187.68,785.16,and 193.20 mg/kg on average,respectively).The BA profiles differed significantly,with CP samples containing higher contents of putrescine,tyramine,and histamine(P<0.05)at the end of fermentation.Metagenomic analysis indicated that BA-producing genes exhibited different abundance profiles,with most genes,including spe A,spe B,arg,spe E,and tyr DC,having higher abundances in microbial communities during the CP process.In total,15 high-quality metagenome-assembled genomes(MAGs)were retrieved,of which 10 encoded at BA production-related genes.Enterococcus faecium(MAG10)and Weissella paramesenteroides(MAG5)might be the major tyramine producers.The high putrescine content in CP might be associated with the high abundance of Staphylococcus gallinarum(MAG8).This study provides a comprehensive understanding of the diversity and abundance of genes involved in BA synthesis,especially at the species level,during food fermentation.展开更多
N-substituted furfurylamines(FAs)are valuable precursors for producing pharmacologically active compounds and polymers.However,enzymatic synthesis of the type of chemicals is still in its infancy.Here we report an imi...N-substituted furfurylamines(FAs)are valuable precursors for producing pharmacologically active compounds and polymers.However,enzymatic synthesis of the type of chemicals is still in its infancy.Here we report an imine reductase from Streptomyces albidoflavus(SaIRED)for the reductive amination of biobased furans.A simple,fast and interference-resistant high-throughput screening(HTS)method was developed,based on the coloration reaction of carbonyl compounds with 2,4-dinitrophenylhydrazine.The reductive amination activity of IREDs can be directly indicated by a colorimetric assay.With the reductive amination of furfural with allylamine as the model reaction,SaIRED with the activity of 4.8 U mg^(-1) was subjected to three rounds of protein engineering and screening by this HTS method,affording a high-activity tri-variant I127V/D241A/A242T(named M3,20.2 U mg^(-1)).The variant M3 showed broad substrate scope,and enabled efficient reductive amination of biobased furans with a variety of amines including small aliphatic amines and sterically hindered amines,giving the target FAs in yields up to>99%.In addition,other variants were identified for preparative-scale synthesis of commercially interesting amines such as N-2-(methylsulfonyl)ethyl-FA by the screen method,with isolated yields up to 87%and turnover numbers up to 9700 for enzyme.Gram-scale synthesis of N-allyl-FA,a valuable building block and potential polymer monomer,was implemented at 0.25 mol L^(-1) substrate loading by a whole-cell catalyst incorporating variant M3,with 4.7 g L^(-1) h^(-1) space-time yield and 91%isolated yield.展开更多
Organic amine pesticides(OAPs)are widely used in modern agriculture and these compounds can contaminate drinking water sources in different ways.However,there is a lack of data on the occurrence of OAPs in drinking wa...Organic amine pesticides(OAPs)are widely used in modern agriculture and these compounds can contaminate drinking water sources in different ways.However,there is a lack of data on the occurrence of OAPs in drinking water and their potential human health risks.In this study,tapwater(TW)and bottledwater(BW)sampleswere collected from eight cities in the Yangtze River Delta urban agglomeration in China,and their OAP levelswere analyzed using high-throughput organic analysis testing coupled with high-volume solid-phase extraction(Hi-throat/Hi-volume SPE techniques).This study is the first to systematically characterize the trace levels of OAPs in drinking water in China.Our findings indicated that the total concentration of OAPs(OAPs)in TW(average 11.06±4.99 ng/L)was 29.4%higher than in BW(average 8.55±3.98 ng/L)and fewer kinds(7)of OAPs were detected in BW.Furthermore,the long-term intake of TW in some areas was linked to carcinogenic risks even at an acceptable OAP range,particularly in males,with molinate being the major contributor(61.3%)to OAP exposure.Further analysis revealed that the occurrence and health risks of OAPs in drinking water were mainly influenced by the quality of water sources and the technologies adopted in drinking water treatment plants(DWTPs).Furthermore,our findings demonstrated that advanced treatment technologies such as nanofiltration could more effectively remove OAPs in raw water(up to 87.5%).Therefore,our findings highlighted the importance of selecting appropriate advanced treatment technologies in DWTPs.展开更多
An electronic circular dichroism(ECD)-based chiroptical sensing method has been developed forβ-andγ-chiral primary amines via a C-H activation reaction.With the addition of Pd(OAc)_(2),the flexible remote chiral pri...An electronic circular dichroism(ECD)-based chiroptical sensing method has been developed forβ-andγ-chiral primary amines via a C-H activation reaction.With the addition of Pd(OAc)_(2),the flexible remote chiral primary amine fragment in the bidentate ligand intermediate was fixed to form a cyclopalladium complex,producing an intense ECD response.The correlation between the sign of Cotton effects and the absolute configuration of substrates was proposed,together with theoretical verification using timedependent density functional theory(TDDFT).Chiroptical sensing of an important drug raw material was performed to provide rapid and accurate information on the absolute optical purity.This work introduces an alternative perspective of C-H activation reaction as well as a feasible chiroptical sensing method of remote chiral amines.展开更多
Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their pra...Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their practical applications for flue gas CO_(2) capture.In this work,we reveal that the nature of surface hydroxyl groups(metal hydroxyl Al–OH and nonmetal hydroxyl Si–OH)plays a key role in the deactivation mechanisms.The polyethyleneimine(PEI)supported on Al–OH-containing substrates suffers from severe oxidative degradation during the CO_(2) capture step due to the breakage of amine-support hydrogen bonding networks,but exhibits an excellent anti-urea formation feature by preventing dehydration of carbamate products under a pure CO_(2) regeneration atmosphere.In contrast,PEI supported on Si–OHcontaining substrates exhibits excellent anti-oxidative stability under simulated flue gas conditions by forming a robust hydrogen bonding protective network with Si–OH,but suffers from obvious urea formation during the pure CO_(2) regeneration step.We also reveal that the urea formation problem for PEI-SBA-15 can be avoided by the incorporation of an OH-containing PEG additive.Based on the intrinsic understanding of degradation mechanisms,we successfully synthesized an adsorbent 40PEI-20PEG-SBA-15 that demonstrates outstanding stability and retention of a high CO_(2) capacity of 2.45 mmol g^(−1) over 1000 adsorption–desorption cycles,together with negligible capacity loss during aging in simulated flue gas(10%CO_(2)+5%O_(2)+3%H_(2)O)for one month at 60–70℃.We believe this work makes great contribution to the advancement in the field of ultra-stable solid amine-based CO_(2) capture materials.展开更多
Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bon...Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bonds using individual ethylenediamine(EDA)molecules.Our approach witnesses a remarkable photocatalytic hydrogen evolution(PHE)competence of 65.93 mmol g^(−1)h^(−1)driven by visible light,the highest value yielded by CIZS to date.X-ray absorption spectra of CIZS and density functional theory(DFT)calculations confirm the crucial amine N→Cu coordination after amine functionalization.The new emerging coordination via lone-pair electron donation profitably accesses the regulation of the coordination environment,electronic structures,and carrier behavior.Moreover,individual EDA molecule with two-terminal−NH2 group serves as a molecular bridge to hybrid CIZS and NiS_(x)cocatalyst via N→Cu and N→Ni coordination,favorably promoting efficient charge transport.This study provides advances in practical functionalizing photocatalysts.展开更多
Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,ther...Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.展开更多
Point source CO_(2) capture(PSCC)is crucial for decarbonizing various industrial sectors,while direct air capture(DAC)holds promise for removing CO_(2) directly from the air.Sorbents play a critical role in both techn...Point source CO_(2) capture(PSCC)is crucial for decarbonizing various industrial sectors,while direct air capture(DAC)holds promise for removing CO_(2) directly from the air.Sorbents play a critical role in both technologies,with their performances,efficiency,cost,etc.,largely depending on which type is used(physical or chemical).Solid amine sorbents(SAS)employed in the chemical adsorption of CO_(2) are suitable for both PSCC and DAC.SAS offer significant advantages over liquid amines such as monoethanolamine(MEA),due to their ability to perform cyclic adsorption–desorption with much lower energy requirement.The environmental concern associated with MEA can be mitigated by SAS.Support materials have a significantly important role in stabilizing amine and enhancing stability and kinetics;varieties of support materials have been screened at a laboratory scale.One promising support material is a silica gel(SG),which is commercially available and attractive for designing cost-effective sorbents for large-scale CO_(2) capture.Various impregnation methods such as physical adsorption and covalent functionalization have been employed to functionalize silica surfaces with amines.This review provided a comprehensive critical analysis of SG-based SAS for CO_(2) capture.We discussed and evaluated them in terms of their adsorption capacity,adsorption,and desorption conditions,and the kinetics involved in these processes.Finally,we proposed a few recommendations for further development of low-cost,lower carbon footprint SAS for large-scale deployment of CO_(2) capture technology.展开更多
The collecting power of tertiary amines（DRN,DEN and DPN） on kaolinite follows the order of DENDPNDRN.After reacting with DRN,DEN and DPN,the surface potentials of kaolinite increase remarkably,and the recruitments c...The collecting power of tertiary amines（DRN,DEN and DPN） on kaolinite follows the order of DENDPNDRN.After reacting with DRN,DEN and DPN,the surface potentials of kaolinite increase remarkably,and the recruitments caused by collectors also follow the order of DENDPNDRN.The results of dynamics simulation show that the geometries of substituent groups bonding to N are deflected and twisted,and some of bond angles are changed when tertiary amines cations adsorb on kaolinite（001） surface.Based on the results of dynamics simulations and quantum chemistry calculations,the electrostatic forces between three tertiary amines cations and 4×4×3（001） plane of kaolinite are 1.38×10？7 N（DRN12H＋）,1.44×10-6 N（DEN12H＋）,1.383×10-6 N（DPN12H＋）,respectively.展开更多
An optimization study on the amination reaction of epoxy polyisobutylene for synthesis of polyisobutylene amine is presented. The experimental results indicate that n-butanol and ethylenediamine are the suitable solve...An optimization study on the amination reaction of epoxy polyisobutylene for synthesis of polyisobutylene amine is presented. The experimental results indicate that n-butanol and ethylenediamine are the suitable solvent and amination agents for the reaction, respectively. The reaction yield of the amination reaction is notably increased with the enhanced molar ratio of either n-butanol against epoxy polyisobutylene or ethylenediamine against epoxy polyisobutylene. Also, the yield is enhanced with increasing temperature and time during the experimental range. Strikingly, the yield reaches as high as 91. 30% under optimal conditions; with the molar ratio of ethylenediamine, n-butanol and PIBO of 10∶ 6∶ 1, the reaction temperature of 150 ℃ and the reaction time of 6 h. In addition, the yield of the reaction is slightly decreased with the enhanced water content of the system. Accordingly, the mass concentration of water should be controlled within 1. 7% during the reaction.展开更多
Time resolved laser spectroscopy and GC/MS were used to investigate the primary processes and the side reactions occurring in benzophenone and chlorothioxanthone/amine systems used as photoinitiators of radical polyme...Time resolved laser spectroscopy and GC/MS were used to investigate the primary processes and the side reactions occurring in benzophenone and chlorothioxanthone/amine systems used as photoinitiators of radical polymerization. The discrepancy observed between the experimental data and the expected behaviour is accounted for by detrimental chemical reaction involving the ketone triplet state, the ketyl radical and the amine-derived radical.展开更多
N-(3′,4′,5′-Trimethoxycinnamoyl)ortho-aminobenzoic acid(TOA),at the concentration of 80μg/ml,significantly inhibited the antigen-induced contraction of ileum isolated from the actively sensitized guinea-pig.At the...N-(3′,4′,5′-Trimethoxycinnamoyl)ortho-aminobenzoic acid(TOA),at the concentration of 80μg/ml,significantly inhibited the antigen-induced contraction of ileum isolated from the actively sensitized guinea-pig.At the concentrations of 25 and 50μg/ml, TOA inhibited homocytotropic antibody-mediated degranulation of mast cells in the rat mesentery,and also inhibited anaphylactic histamine release from rat peritoneal mast cells.展开更多
基金supported by the National Natural Science Foundation of China(No.52100133,No.52222005)the Key R&D Program of Yunnan Province(No.202303AC100008)。
文摘Catalyst-aided regeneration is a promising method for reducing the high regeneration energy consumption of amine-based CO_(2)capture technologies.However,the intrinsic relationship between the properties of the acidic sites and their catalytic activity is controversial.In this study,a series of W-based catalysts supported by ZrTiO_(x)were synthesised,and the effects of the intensity,distribution,and type of acid sites were systematically investigated by quantitatively regulating the acidic site properties.The results indicate stronger acidic sites play a more important role in the catalytic reaction.Moreover,the catalysts showed excellent performance only if the Br?nsted acid sites(BASs)and Lewis acid sites(LASs)coexisted.During the catalytic reaction,the BASs facilitated deprotonation,and the LASs promoted the decomposition of carbamates.The ratio of BASs to LASs(B/L)was a critical factor for catalytic activity,wherein optimal performance was achieved when the B/L ratio was close to 1.The 10%HPW/ZrTiO_(x)composite performed better than WO_(3)/ZrTiO_(x)and HSiW/ZrTiO_(x)because it had a stronger acid intensity and a suitable B/L ratio.As a result,the relative heat duty was reduced by 47%compared to 30%aqueous MEA,and the maximum CO_(2)desorption rate was increased by 83%.The Bader charge indicated that the W atoms of HPW/ZrTiO_(x)lost more electrons(0.18)than those of WO_(3)/ZrTiO_(x),which can weaken the O±H bond energy.Consequently,the calculated deprotonation energy is as low as 257 kJ mol^(-1)for HPW/ZrTiO_(x).
文摘Amines represent fundamental motifs in various chemical contexts and are widely used in agrochemicals and pharmaceuticals.The development of earth-abundant metal-based heterogeneous catalysts for the synthesis amines remains an important goal in terms of chemical research and industrial application/manufacture.Herein,we developed an efficient and highly selective nitrogen-doped nickel catalyst enriched with Lewis acid sites,which has been applied for to the hydrogenative coupling of nitriles and amines with molecular hydrogen for the synthesis of a train of functionalised and structurally diverse secondary and tertiary amines.Furthermore,catalytic hydrogenation and deuteration of nitriles were achieved under milder conditions,yielding a series of primary amines and deuterated amines with high deuterium incorporation.
基金Funded by the National Natural Science Foundation of China(No.21865017)。
文摘[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was synthesized,using tert-butyldimethylsilane(TBDMS)and 1,2-epoxy-4-vinylcyclohexane(EVC)as the main raw materials and tris(triphenylphosphine)chlororhodium(I)[RhCl(Ph3P)3]as the catalyst.[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane is a novel kind of silicon-containing epoxide.The factors affecting the reaction yield,such as catalyst use,reaction time and reaction temperature,were investigated,and the synthesized product was characterized and analyzed by FT-IR and 1H-NMR.A series of amine-curing resins were prepared with[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane,bisphenol A epoxy resin(E-51)and modified amine(593 amine).The mechanical properties of cured splines with the different proportions of amine-curing resins were tested.When the content of 593 amine was 20%,the content of E-51 was 75%and the amount of[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was 5%,the mechanical properties of the cured splines were the best with the tensile strength being 23.3 MPa,the elongation at break being 7.8%,and the Young's modulus being 421.3 MPa.
基金supported financially by the Excellent Going Abroad Expert's Training Program in Hebei Province (No. 201940)the Hebei Natural Science Foundation of China (No. H2020208030)the S & T Program of Hebei (No. 22567607H) for financial support。
文摘A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the reaction step and atom economy. It has been investigated that the 2,4,6-trimethylpyridine ligand was critical to achieve the optimized reactivity. This protocol provides a straightforward route for synthesizing the alkynylated free benzylamines, featuring good substrate compatibility and monoselectivity.
基金supported by the Key R&D Program of Yunnan Province(No.202303AC100008)the National Natural Science Foundation of China(No.52100133)the Major Science and Technology-Special Plan“Unveiling and Leading”Project of Shanxi Province(No.202201050201011).
文摘The biphasic solvent is a promising solution to reduce regeneration energy consumption in CO_(2) capture.However,most current biphasic solvents suffer from high viscosity and poor desorption of the rich phase.To the issues,a novel pentamethyldiethylenetriamine(PMDETA)-2-amino-2-methyl-1-propanol(AMP)/diethylenetriamine(DETA)-sulfolane biphasic solvent was developed.The mechanism of AMP affecting CO_(2) recycling capacity was analyzed.By adjusting the ratio of AMP and DETA,the absorption and desorption performance were balanced,and the recycling capacity and renewable energy consumption of the absorbent were improved.For the P_(2.4)A_(0.8)D_(0.8)S_(2) biphasic solvent,the CO_(2) loading of the rich phase was 5.87 mol/L,and the proportion of the rich phase volume ratio was 35%,which surpasses most reported biphasic solvents.The viscosity of the absorbent significantly decreased from 527.00 mPa·s to 92.26 mPa·s,attributed to the beneficial effect of AMP.Thermodynamic analysis showed that the biphasic solvent produced a lower regeneration energy consumption of 1.70 GJ/t CO_(2),which was 57%lower than that of monoethanolamine(MEA).Overall,the PMDETA-AMP/DETA-sulfolane biphasic solvent exhibited cycle capacity,which provided new insights for the designing of biphasic solvent.
基金supported by the Natural Science Foundation of Guangdong Province(2022A1515012158)the National Science Foundation of China(41977138)+3 种基金the Construction Project of Teaching Quality and Teaching Reform in Guangdong Province(SJD202001)the General University Project of Guangdong Provincial Department of Education(2021KCXTD070 and 2021ZDZX4072)the Key Project of Social Welfare and Basic Research of Zhongshan City(2020B2010)the Start-up Fund from the Zhongshan Institute at the University of Electronic Science and Technology in China(419YKQN12)。
文摘In-depth knowledge of the microbes responsible for biogenic amine(BA)production during soy sauce fermentation remains limited.Herein,the variations in the BA profiles,microbial communities,and microbes involved in BA production during the fermentation of soy sauce through Japanese-type(JP)and Cantonese-type(CP)processes were compared.BA analysis revealed that the most abundant BA species were putrescine,tyramine,and histamine in the later three stages(1187.68,785.16,and 193.20 mg/kg on average,respectively).The BA profiles differed significantly,with CP samples containing higher contents of putrescine,tyramine,and histamine(P<0.05)at the end of fermentation.Metagenomic analysis indicated that BA-producing genes exhibited different abundance profiles,with most genes,including spe A,spe B,arg,spe E,and tyr DC,having higher abundances in microbial communities during the CP process.In total,15 high-quality metagenome-assembled genomes(MAGs)were retrieved,of which 10 encoded at BA production-related genes.Enterococcus faecium(MAG10)and Weissella paramesenteroides(MAG5)might be the major tyramine producers.The high putrescine content in CP might be associated with the high abundance of Staphylococcus gallinarum(MAG8).This study provides a comprehensive understanding of the diversity and abundance of genes involved in BA synthesis,especially at the species level,during food fermentation.
文摘N-substituted furfurylamines(FAs)are valuable precursors for producing pharmacologically active compounds and polymers.However,enzymatic synthesis of the type of chemicals is still in its infancy.Here we report an imine reductase from Streptomyces albidoflavus(SaIRED)for the reductive amination of biobased furans.A simple,fast and interference-resistant high-throughput screening(HTS)method was developed,based on the coloration reaction of carbonyl compounds with 2,4-dinitrophenylhydrazine.The reductive amination activity of IREDs can be directly indicated by a colorimetric assay.With the reductive amination of furfural with allylamine as the model reaction,SaIRED with the activity of 4.8 U mg^(-1) was subjected to three rounds of protein engineering and screening by this HTS method,affording a high-activity tri-variant I127V/D241A/A242T(named M3,20.2 U mg^(-1)).The variant M3 showed broad substrate scope,and enabled efficient reductive amination of biobased furans with a variety of amines including small aliphatic amines and sterically hindered amines,giving the target FAs in yields up to>99%.In addition,other variants were identified for preparative-scale synthesis of commercially interesting amines such as N-2-(methylsulfonyl)ethyl-FA by the screen method,with isolated yields up to 87%and turnover numbers up to 9700 for enzyme.Gram-scale synthesis of N-allyl-FA,a valuable building block and potential polymer monomer,was implemented at 0.25 mol L^(-1) substrate loading by a whole-cell catalyst incorporating variant M3,with 4.7 g L^(-1) h^(-1) space-time yield and 91%isolated yield.
基金supported by the National Key Research and Development Program of China(No.2019YFD1100203).
文摘Organic amine pesticides(OAPs)are widely used in modern agriculture and these compounds can contaminate drinking water sources in different ways.However,there is a lack of data on the occurrence of OAPs in drinking water and their potential human health risks.In this study,tapwater(TW)and bottledwater(BW)sampleswere collected from eight cities in the Yangtze River Delta urban agglomeration in China,and their OAP levelswere analyzed using high-throughput organic analysis testing coupled with high-volume solid-phase extraction(Hi-throat/Hi-volume SPE techniques).This study is the first to systematically characterize the trace levels of OAPs in drinking water in China.Our findings indicated that the total concentration of OAPs(OAPs)in TW(average 11.06±4.99 ng/L)was 29.4%higher than in BW(average 8.55±3.98 ng/L)and fewer kinds(7)of OAPs were detected in BW.Furthermore,the long-term intake of TW in some areas was linked to carcinogenic risks even at an acceptable OAP range,particularly in males,with molinate being the major contributor(61.3%)to OAP exposure.Further analysis revealed that the occurrence and health risks of OAPs in drinking water were mainly influenced by the quality of water sources and the technologies adopted in drinking water treatment plants(DWTPs).Furthermore,our findings demonstrated that advanced treatment technologies such as nanofiltration could more effectively remove OAPs in raw water(up to 87.5%).Therefore,our findings highlighted the importance of selecting appropriate advanced treatment technologies in DWTPs.
基金supported by the CAMS Innovation Fund for Medical Sciences(CIFMS,No.2023-I2M-2-009).
文摘An electronic circular dichroism(ECD)-based chiroptical sensing method has been developed forβ-andγ-chiral primary amines via a C-H activation reaction.With the addition of Pd(OAc)_(2),the flexible remote chiral primary amine fragment in the bidentate ligand intermediate was fixed to form a cyclopalladium complex,producing an intense ECD response.The correlation between the sign of Cotton effects and the absolute configuration of substrates was proposed,together with theoretical verification using timedependent density functional theory(TDDFT).Chiroptical sensing of an important drug raw material was performed to provide rapid and accurate information on the absolute optical purity.This work introduces an alternative perspective of C-H activation reaction as well as a feasible chiroptical sensing method of remote chiral amines.
基金supported by the Fundamental Research Funds for the National Natural Science Foundation of China 52225003,22208021,22109004the National Key R&D Program of China 2022YFB4101702.
文摘Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their practical applications for flue gas CO_(2) capture.In this work,we reveal that the nature of surface hydroxyl groups(metal hydroxyl Al–OH and nonmetal hydroxyl Si–OH)plays a key role in the deactivation mechanisms.The polyethyleneimine(PEI)supported on Al–OH-containing substrates suffers from severe oxidative degradation during the CO_(2) capture step due to the breakage of amine-support hydrogen bonding networks,but exhibits an excellent anti-urea formation feature by preventing dehydration of carbamate products under a pure CO_(2) regeneration atmosphere.In contrast,PEI supported on Si–OHcontaining substrates exhibits excellent anti-oxidative stability under simulated flue gas conditions by forming a robust hydrogen bonding protective network with Si–OH,but suffers from obvious urea formation during the pure CO_(2) regeneration step.We also reveal that the urea formation problem for PEI-SBA-15 can be avoided by the incorporation of an OH-containing PEG additive.Based on the intrinsic understanding of degradation mechanisms,we successfully synthesized an adsorbent 40PEI-20PEG-SBA-15 that demonstrates outstanding stability and retention of a high CO_(2) capacity of 2.45 mmol g^(−1) over 1000 adsorption–desorption cycles,together with negligible capacity loss during aging in simulated flue gas(10%CO_(2)+5%O_(2)+3%H_(2)O)for one month at 60–70℃.We believe this work makes great contribution to the advancement in the field of ultra-stable solid amine-based CO_(2) capture materials.
基金supported by the National Natural Science Foundation of China(No.62304219)the Strategic Priority Research Program of theChinese Academy of Sciences(No.XDB43000000)+1 种基金the CAS Project for Young Scientists in Basic Research(YSBR−090)the National Natural ScienceFoundation of China(Nos.21975245,U20A20206,and 51972300)。
文摘Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bonds using individual ethylenediamine(EDA)molecules.Our approach witnesses a remarkable photocatalytic hydrogen evolution(PHE)competence of 65.93 mmol g^(−1)h^(−1)driven by visible light,the highest value yielded by CIZS to date.X-ray absorption spectra of CIZS and density functional theory(DFT)calculations confirm the crucial amine N→Cu coordination after amine functionalization.The new emerging coordination via lone-pair electron donation profitably accesses the regulation of the coordination environment,electronic structures,and carrier behavior.Moreover,individual EDA molecule with two-terminal−NH2 group serves as a molecular bridge to hybrid CIZS and NiS_(x)cocatalyst via N→Cu and N→Ni coordination,favorably promoting efficient charge transport.This study provides advances in practical functionalizing photocatalysts.
基金supported by the National Natural Science Foundation of China(Nos.42177354 and 42020104001)the National Key R&D Program of China(No.2019YFC0214402)+1 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)Guangdong Basic and Applied Basic Research Foundation(No.2019B151502064).
文摘Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.
基金financial support from Business Finland 8205/31/2022the Magnus Ehrnrooth Foundation for financial support.
文摘Point source CO_(2) capture(PSCC)is crucial for decarbonizing various industrial sectors,while direct air capture(DAC)holds promise for removing CO_(2) directly from the air.Sorbents play a critical role in both technologies,with their performances,efficiency,cost,etc.,largely depending on which type is used(physical or chemical).Solid amine sorbents(SAS)employed in the chemical adsorption of CO_(2) are suitable for both PSCC and DAC.SAS offer significant advantages over liquid amines such as monoethanolamine(MEA),due to their ability to perform cyclic adsorption–desorption with much lower energy requirement.The environmental concern associated with MEA can be mitigated by SAS.Support materials have a significantly important role in stabilizing amine and enhancing stability and kinetics;varieties of support materials have been screened at a laboratory scale.One promising support material is a silica gel(SG),which is commercially available and attractive for designing cost-effective sorbents for large-scale CO_(2) capture.Various impregnation methods such as physical adsorption and covalent functionalization have been employed to functionalize silica surfaces with amines.This review provided a comprehensive critical analysis of SG-based SAS for CO_(2) capture.We discussed and evaluated them in terms of their adsorption capacity,adsorption,and desorption conditions,and the kinetics involved in these processes.Finally,we proposed a few recommendations for further development of low-cost,lower carbon footprint SAS for large-scale deployment of CO_(2) capture technology.
基金Project (2005CB623701) supported by the National Basic Research Program of China Project (201011031) supported by National Department Public Benefit Research Foundation from Ministry of Land and Resources of China+1 种基金 Project (2935) supported by the Foundation for the Author of Zhengzhou Institute of Multipurpose Utilization of Mineral Resources CAGS, China Project (1212011120304) supported by the Geological Surrey Program
文摘The collecting power of tertiary amines（DRN,DEN and DPN） on kaolinite follows the order of DENDPNDRN.After reacting with DRN,DEN and DPN,the surface potentials of kaolinite increase remarkably,and the recruitments caused by collectors also follow the order of DENDPNDRN.The results of dynamics simulation show that the geometries of substituent groups bonding to N are deflected and twisted,and some of bond angles are changed when tertiary amines cations adsorb on kaolinite（001） surface.Based on the results of dynamics simulations and quantum chemistry calculations,the electrostatic forces between three tertiary amines cations and 4×4×3（001） plane of kaolinite are 1.38×10？7 N（DRN12H＋）,1.44×10-6 N（DEN12H＋）,1.383×10-6 N（DPN12H＋）,respectively.
基金The Natural Science Foundation of Jiangsu Province(No.BK20130602)the Project of the Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘An optimization study on the amination reaction of epoxy polyisobutylene for synthesis of polyisobutylene amine is presented. The experimental results indicate that n-butanol and ethylenediamine are the suitable solvent and amination agents for the reaction, respectively. The reaction yield of the amination reaction is notably increased with the enhanced molar ratio of either n-butanol against epoxy polyisobutylene or ethylenediamine against epoxy polyisobutylene. Also, the yield is enhanced with increasing temperature and time during the experimental range. Strikingly, the yield reaches as high as 91. 30% under optimal conditions; with the molar ratio of ethylenediamine, n-butanol and PIBO of 10∶ 6∶ 1, the reaction temperature of 150 ℃ and the reaction time of 6 h. In addition, the yield of the reaction is slightly decreased with the enhanced water content of the system. Accordingly, the mass concentration of water should be controlled within 1. 7% during the reaction.
文摘Time resolved laser spectroscopy and GC/MS were used to investigate the primary processes and the side reactions occurring in benzophenone and chlorothioxanthone/amine systems used as photoinitiators of radical polymerization. The discrepancy observed between the experimental data and the expected behaviour is accounted for by detrimental chemical reaction involving the ketone triplet state, the ketyl radical and the amine-derived radical.
文摘N-(3′,4′,5′-Trimethoxycinnamoyl)ortho-aminobenzoic acid(TOA),at the concentration of 80μg/ml,significantly inhibited the antigen-induced contraction of ileum isolated from the actively sensitized guinea-pig.At the concentrations of 25 and 50μg/ml, TOA inhibited homocytotropic antibody-mediated degranulation of mast cells in the rat mesentery,and also inhibited anaphylactic histamine release from rat peritoneal mast cells.
