N-formylation of amines,a class of synthetically important reactions,is typically conducted using metal catalysts that are relatively expensive or not readily available and usually needs harsh conditions to increase t...N-formylation of amines,a class of synthetically important reactions,is typically conducted using metal catalysts that are relatively expensive or not readily available and usually needs harsh conditions to increase the reaction efficiency.Here,an efficient continuous microflow strategy was developed for the gas-liquid visible-light photocatalytic N-formylation of piperidine,which achieved a reaction yield of 82.97%and a selectivity of>99%at 12 min using cheap organic dye photocatalyst under mild reaction conditions.The influence of essential parameters,including light intensity,temperature and equivalents of the gas,additive and photocatalyst,on the reaction yield was systematically studied.Furthermore,kinetic investigations were conducted,exhibiting the dependence of reaction rate and equilibrium yield of N-formylpiperidine on light intensity,temperature and photocatalyst equivalent.The microflow photocatalytic approach established in this work,which realized a markedly higher space-time yield than the conventional batch method(37.9 vs.0.212 mmol h-1 L-1),paves the way for the continuous,green and efficient synthesis of N-formamides.展开更多
Designing highly efficient photocatalyst for the valorization of CO_(2) is an ideal strategy to reduce greenhouse gas emissions and utilize solar energy.In this study,a S-scheme heterojunction photocatalyst is fabrica...Designing highly efficient photocatalyst for the valorization of CO_(2) is an ideal strategy to reduce greenhouse gas emissions and utilize solar energy.In this study,a S-scheme heterojunction photocatalyst is fabricated by solvothermal impregnation of ZnO on W_(18)O_(49) for photocatalytic CO_(2) N-formylation of aniline.The localized surface plasmon resonance effect of W_(18)O_(49) improves the absorption capacity for long-wave light significantly,and the hot electrons generated in W_(18)O_(49) with a high energy can migrate to the conduction band of ZnO and thus enhance the photocatalytic reduction ability.Meanwhile,the S-scheme heterojunction facilitates the separation of photoinduced charge carriers and preserves the redox ability of W_(18)O_(49)/ZnO composite photocatalyst.The conversion of aniline reaches 99.1%after 5 h reaction under visible light irradiation at room temperature with an N-formylaniline selectivity of 100%.A possible photocatalytic reaction mechanism is proposed.This study paves a promising way for the design of highly efficient photocatalyst and the sustainable utilization of CO_(2).展开更多
A series of SO_(3)-functional Br?nsted acidic ionic liquids(SBAILs)were prepared to catalyze the Nformylation of aniline with DMF.The reaction conditions such as ionic liquid type,reaction temperature.catalyst loading...A series of SO_(3)-functional Br?nsted acidic ionic liquids(SBAILs)were prepared to catalyze the Nformylation of aniline with DMF.The reaction conditions such as ionic liquid type,reaction temperature.catalyst loading and molar ratio of reactants were investigated.To the best of our knowledge,kinetic model for the N-formylation of aniline with DMF using SBAIL was firstly built and simulated.The studies on the reaction order of the reaction were evaluated by initial concentration method,and the kinetic parameters such as reaction rate constant and activation energy were proposed and used to explain the catalytic activities of the SBAILs catalysts.Accordingly,the recycling experiments showed that the SBAIL[Bsmim][HSO_(4)]can be easily recovered and reused with stable activity.Further,the temperature-controlled study emphasized that the ionic liquid was easy to be separated and environmentally friendly.展开更多
Due to its difficulty and complexity,the cleavage and subsequent functionalization of the C(sp^(3))-C(sp^(3))single bond has received less attention than the C-C bond formation reactions that have been extensively stu...Due to its difficulty and complexity,the cleavage and subsequent functionalization of the C(sp^(3))-C(sp^(3))single bond has received less attention than the C-C bond formation reactions that have been extensively studied.Herein,by utilizing Cu/g-C_(3)N_(4)nanometric semiconductor as a recyclable photocatalyst,an aerobic oxidative C-C bond cleavage of aldehydes was developed with the promotion of amines under visible light irradiation.Based on the reaction,phenylacetaldehyde was selected as a highly efficient formylation reagent for amines.Under blue light irradiation,good to excellent yields of formamides were achieved for various amines in 1 atm oxygen atmosphere at room temperature.This methodology offers a practical,neutral and gentle alternative to the preparation of formamides.展开更多
Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the ...Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the supports.It was indicated that the resultant Pd/NC catalysts were effective for N-formylation of amines with CO_2and H_2in ethanol without any additives.Especially,the catalyst Pd/NC-800-6.9%containing quaternary N showed the best performance,affording a series of formylamides in good or even excellent yields.Further investigation reveals that the interaction between the Pd nanoparticles and quaternary nitrogen in the NC support was responsible for the good performance of the catalyst.展开更多
An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The...An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The key advantages of this protocol are the shorter reaction time,higher yields,lower cost,simple workup,and environment-friendly compared to conventional organic solvent reaction.The present method does not involve any hazardous organic solvent or catalyst.展开更多
A rapid and practical green route for the N-formylation of amines with formic acid using Amberlite IR-120 as a catalyst is described.This method provides an efficient and much improved modification over the reported m...A rapid and practical green route for the N-formylation of amines with formic acid using Amberlite IR-120 as a catalyst is described.This method provides an efficient and much improved modification over the reported methods in terms of yield,reaction time,and work-up procedure.A wide variety of substituents is tolerated,which is not the case for existing procedures.展开更多
Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO_2 were designed, which could capture CO_2 with capacity >1.0 mol CO_2 per molar IL under ambient conditions. Moreover, this...Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO_2 were designed, which could capture CO_2 with capacity >1.0 mol CO_2 per molar IL under ambient conditions. Moreover, this kind of ILs combining with Cu Cl could catalyze the formylation of amines with CO_2/H_2 at 120 °C. Especially, choline imidazolate showed the best performance,affording a series of N-formamides in excellent yields. It was demonstrated that the IL activated CO_2 and the synergistic effect between the IL and Cu Cl resulted in the high activity for catalysing the formylation of amines with CO_2/H_2.展开更多
The N-formylation of amines with CO_(2)and hydrosilanes is an emerging yet important reaction in fine chemical industry.Herein,we have reported a methyltrioctylammonium cation(TOMA)stabilized Nb oxocluster catalyst th...The N-formylation of amines with CO_(2)and hydrosilanes is an emerging yet important reaction in fine chemical industry.Herein,we have reported a methyltrioctylammonium cation(TOMA)stabilized Nb oxocluster catalyst that can effectively realize two electron reduction of CO_(2)and form C-N bond simultaneously,leading to the corresponding formamides.The oxocluster catalyst exhibits excellent catalytic activity to transform secondary and primary amines into the corresponding formamides,with the conversion ranging from 81.5%to 99.2%under room temperature conditions.Furthermore,the Nb oxocluster catalyst shows the unique characteristics of ionic liquids,and it is highly robust and easy to be recycled for five times with negligible loss of catalytic activity.On the basis of the activity tests and structure characterization of Nb catalysts,it was found that TOMA cation played an important role in modulating the Nb oxocluster with high stability and uniform dispersion.The mechanism studies demonstrate that the formylation reaction proceeds through the formation of silyl formate intermediate rather than carbamate,and the Lewis base site of negative oxygen atoms from polyoxoniobate anions can exert a favorable impact on activation both CO_(2)and Si-H bond of PhSiH 3,allowing that N-formylation reaction proceed smoothly under very mild reaction conditions.展开更多
基金the financial support from the National Natural Science Foundation of China(No.21808059)the Fundamental Research Funds for the Central Universities(No.JKA01221712).
文摘N-formylation of amines,a class of synthetically important reactions,is typically conducted using metal catalysts that are relatively expensive or not readily available and usually needs harsh conditions to increase the reaction efficiency.Here,an efficient continuous microflow strategy was developed for the gas-liquid visible-light photocatalytic N-formylation of piperidine,which achieved a reaction yield of 82.97%and a selectivity of>99%at 12 min using cheap organic dye photocatalyst under mild reaction conditions.The influence of essential parameters,including light intensity,temperature and equivalents of the gas,additive and photocatalyst,on the reaction yield was systematically studied.Furthermore,kinetic investigations were conducted,exhibiting the dependence of reaction rate and equilibrium yield of N-formylpiperidine on light intensity,temperature and photocatalyst equivalent.The microflow photocatalytic approach established in this work,which realized a markedly higher space-time yield than the conventional batch method(37.9 vs.0.212 mmol h-1 L-1),paves the way for the continuous,green and efficient synthesis of N-formamides.
文摘Designing highly efficient photocatalyst for the valorization of CO_(2) is an ideal strategy to reduce greenhouse gas emissions and utilize solar energy.In this study,a S-scheme heterojunction photocatalyst is fabricated by solvothermal impregnation of ZnO on W_(18)O_(49) for photocatalytic CO_(2) N-formylation of aniline.The localized surface plasmon resonance effect of W_(18)O_(49) improves the absorption capacity for long-wave light significantly,and the hot electrons generated in W_(18)O_(49) with a high energy can migrate to the conduction band of ZnO and thus enhance the photocatalytic reduction ability.Meanwhile,the S-scheme heterojunction facilitates the separation of photoinduced charge carriers and preserves the redox ability of W_(18)O_(49)/ZnO composite photocatalyst.The conversion of aniline reaches 99.1%after 5 h reaction under visible light irradiation at room temperature with an N-formylaniline selectivity of 100%.A possible photocatalytic reaction mechanism is proposed.This study paves a promising way for the design of highly efficient photocatalyst and the sustainable utilization of CO_(2).
基金financial support of National Natural Science Foundation of China(21776122)the Fundamental Research Funds for the Central Universities。
文摘A series of SO_(3)-functional Br?nsted acidic ionic liquids(SBAILs)were prepared to catalyze the Nformylation of aniline with DMF.The reaction conditions such as ionic liquid type,reaction temperature.catalyst loading and molar ratio of reactants were investigated.To the best of our knowledge,kinetic model for the N-formylation of aniline with DMF using SBAIL was firstly built and simulated.The studies on the reaction order of the reaction were evaluated by initial concentration method,and the kinetic parameters such as reaction rate constant and activation energy were proposed and used to explain the catalytic activities of the SBAILs catalysts.Accordingly,the recycling experiments showed that the SBAIL[Bsmim][HSO_(4)]can be easily recovered and reused with stable activity.Further,the temperature-controlled study emphasized that the ionic liquid was easy to be separated and environmentally friendly.
基金the financial support from the National Natural Science Foundation of China(Nos.21772091,21472092 to X.Yao)funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Due to its difficulty and complexity,the cleavage and subsequent functionalization of the C(sp^(3))-C(sp^(3))single bond has received less attention than the C-C bond formation reactions that have been extensively studied.Herein,by utilizing Cu/g-C_(3)N_(4)nanometric semiconductor as a recyclable photocatalyst,an aerobic oxidative C-C bond cleavage of aldehydes was developed with the promotion of amines under visible light irradiation.Based on the reaction,phenylacetaldehyde was selected as a highly efficient formylation reagent for amines.Under blue light irradiation,good to excellent yields of formamides were achieved for various amines in 1 atm oxygen atmosphere at room temperature.This methodology offers a practical,neutral and gentle alternative to the preparation of formamides.
基金supported by the Chinese Academy of Sciences (QYZDY-SSW-SLH013)the National Natural Science Foundation of China (21533011, 21503239)
文摘Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the supports.It was indicated that the resultant Pd/NC catalysts were effective for N-formylation of amines with CO_2and H_2in ethanol without any additives.Especially,the catalyst Pd/NC-800-6.9%containing quaternary N showed the best performance,affording a series of formylamides in good or even excellent yields.Further investigation reveals that the interaction between the Pd nanoparticles and quaternary nitrogen in the NC support was responsible for the good performance of the catalyst.
基金support from the Natural Science Foundation of Gansu Province(No.3ZS061- A25-019)the Scientific Research fund of Gansu Provincial Education Department(No.0601-25)
文摘An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The key advantages of this protocol are the shorter reaction time,higher yields,lower cost,simple workup,and environment-friendly compared to conventional organic solvent reaction.The present method does not involve any hazardous organic solvent or catalyst.
文摘A rapid and practical green route for the N-formylation of amines with formic acid using Amberlite IR-120 as a catalyst is described.This method provides an efficient and much improved modification over the reported methods in terms of yield,reaction time,and work-up procedure.A wide variety of substituents is tolerated,which is not the case for existing procedures.
基金supported by the Chinese Academy of Sciences (QYZDY-SSW-SLH013)the National Natural Science Foundation of China (21673068, 21533011)
文摘Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO_2 were designed, which could capture CO_2 with capacity >1.0 mol CO_2 per molar IL under ambient conditions. Moreover, this kind of ILs combining with Cu Cl could catalyze the formylation of amines with CO_2/H_2 at 120 °C. Especially, choline imidazolate showed the best performance,affording a series of N-formamides in excellent yields. It was demonstrated that the IL activated CO_2 and the synergistic effect between the IL and Cu Cl resulted in the high activity for catalysing the formylation of amines with CO_2/H_2.
基金The authors are grateful for financial support from the National Natural Science Foundation of China(21773061,21978095).
文摘The N-formylation of amines with CO_(2)and hydrosilanes is an emerging yet important reaction in fine chemical industry.Herein,we have reported a methyltrioctylammonium cation(TOMA)stabilized Nb oxocluster catalyst that can effectively realize two electron reduction of CO_(2)and form C-N bond simultaneously,leading to the corresponding formamides.The oxocluster catalyst exhibits excellent catalytic activity to transform secondary and primary amines into the corresponding formamides,with the conversion ranging from 81.5%to 99.2%under room temperature conditions.Furthermore,the Nb oxocluster catalyst shows the unique characteristics of ionic liquids,and it is highly robust and easy to be recycled for five times with negligible loss of catalytic activity.On the basis of the activity tests and structure characterization of Nb catalysts,it was found that TOMA cation played an important role in modulating the Nb oxocluster with high stability and uniform dispersion.The mechanism studies demonstrate that the formylation reaction proceeds through the formation of silyl formate intermediate rather than carbamate,and the Lewis base site of negative oxygen atoms from polyoxoniobate anions can exert a favorable impact on activation both CO_(2)and Si-H bond of PhSiH 3,allowing that N-formylation reaction proceed smoothly under very mild reaction conditions.