The synthesis of new indoloannulated thiopyranethiones is reported. The key-step is a rhodium-catalyzed [2 + 2 + 2]-cycloaddition of alkynyl-ynamides with carbon disulfide to close the pyrrole and the thiopyranethione...The synthesis of new indoloannulated thiopyranethiones is reported. The key-step is a rhodium-catalyzed [2 + 2 + 2]-cycloaddition of alkynyl-ynamides with carbon disulfide to close the pyrrole and the thiopyranethione rings simultaneously. A violet idolothiopyrane thione or a mixture of the violet and a red isomer result from [RhCl(C<sub>8</sub>H<sub>14</sub>)<sub>2</sub>]<sub>2</sub>/3BINAP catalyzed cycloadditions, the regiochemistry is controlled by the substitution pattern on the alkynyl-ynamide.展开更多
A double active center system, namely Salen-Cu（Ⅱ）@MIL-101（Cr）, was successfully synthesized via the"ship in a bottle" approach, which acted as a bifunctional material for both capture and conversion of ...A double active center system, namely Salen-Cu（Ⅱ）@MIL-101（Cr）, was successfully synthesized via the"ship in a bottle" approach, which acted as a bifunctional material for both capture and conversion of COin a single process. For the first time, Salen-Cu（Ⅱ）@MIL-101（Cr） catalyst was developed for the synthesis of propylene carbonate from COand propylene oxide under room temperature and ambient pressure with a yield of 87.8% over 60 h. Furthermore, the reaction mechanism was also discussed.展开更多
1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of pr...1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of preparing fused heterocyclic compounds was offered by 1,3-dipolar cycloaddition reaction of silyl nitronates to 1.展开更多
Two kinds of bi-functional transition metal doped mesoporous materials(Fe-HMS and Fe-MCM-41) are prepared using one-step hydrothermal method and then treated with hydrochloric acid ethanol solution.The N2 adsorption a...Two kinds of bi-functional transition metal doped mesoporous materials(Fe-HMS and Fe-MCM-41) are prepared using one-step hydrothermal method and then treated with hydrochloric acid ethanol solution.The N2 adsorption and HRTEM results show that both of Fe-HMS and Fe-MCM-41 possess mesoporous structure. The UV–vis results suggest that the Fe species are mainly located within the framework. The basicity of as-prepared samples was studied by temperature programmed desorption using CO2 as probe molecule(CO2-TPD). The catalytic performance of Fe-HMS and Fe-MCM-41 in CO2 cycloaddition largely depends on the amount of the accessible basic sites. The acid–base active sites, framework Fe and PDDA species cooperatively catalyze the CO2 cycloaddition for the production of cyclic carbonates under the condition without any co-catalyst. The conversion of epichlorohydrin(ECH) is 97.4% and the selectivity of chloropropene carbonate is 92.9% under optimal conditions. The approximate rate constant of cycloaddition reaction of CO2 with ECH under optimum reaction temperature is calculated. It is worth noting that the Fe-HMS material shows superior reusability than Fe-MCM-41. In addition, this work provides a facile way on the synthesis of bi-functional acid–base heterogeneous catalyst with outstanding catalytic performance for the fixation of CO2.展开更多
facile one-step method is presented for the synthesis of indolizines in moder-ate to high yields by reaction of pyridinium, quinolinium and isoquinolinium ylideswith acrylonitrile, methyl acrylate and diethyl maleate ...facile one-step method is presented for the synthesis of indolizines in moder-ate to high yields by reaction of pyridinium, quinolinium and isoquinolinium ylideswith acrylonitrile, methyl acrylate and diethyl maleate respectively in the presenceof tetrakis-pyridino-cobalt(Ⅱ)dichromate (TPCD) in DMF.展开更多
Dihydro-1H-1, 5-benzodiazepines and 1-benzoy1-2, 3-dihydro-1H-1H-1,5-benzodiazepines react with .α-carbonylkelenes, generated from 2-diazo-1,3-diphenyl-1,3-propandione or 2-diazo-1-phenyl-1,3-butandione by heating, t...Dihydro-1H-1, 5-benzodiazepines and 1-benzoy1-2, 3-dihydro-1H-1H-1,5-benzodiazepines react with .α-carbonylkelenes, generated from 2-diazo-1,3-diphenyl-1,3-propandione or 2-diazo-1-phenyl-1,3-butandione by heating, to give 4a,5, 6, 12-letralydro- 1H,7H-1,3-oxazino[3,2-d][1,5]-benzodiazepine-1-ones,a new ring system. 2, 3-Dihydro-1H-1,5-benzodiazepines also afford,dducts of H-N bond,with a carbonylketenes, 2-aryt-1-(2-benzoyl-phenylacelyl)-4-phenyl-2,3-dihydro-1H-1,5-benzodiazepines. Addition of henzonitrile N-phenylimine,yielde in situ from the N-phenyl benzenecarbohydrazic chloride,to 2, 4-diaryl-2, 3-dihydro-1,5-benzothiazepines and 1H-1,5-benzodiazepine gave 3a, 5-diaryl-1, 3-diphenyl-3a, 4, 5, 11 tetralydro-3H-1, 2, 4-triazolo [4, 3-d][1. 5]benzothiazepine and 3H,6H-1, 2, 4 triazolo[4, 3-d][1, 5] benzodiazpine, respectively.展开更多
1 Introduction Fullerene has received considerable attention and a great researching interest due to its unique structure and interesting properties[1―3]. Many functional groups have been introduced, often region- or...1 Introduction Fullerene has received considerable attention and a great researching interest due to its unique structure and interesting properties[1―3]. Many functional groups have been introduced, often region- or stereo-selectively, for tuning the physical properties of C60and for constructing supramoleculararchitectures^[4-6].展开更多
Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were c...Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were characterized. Click reaction of azide and alkyne functionals catalyzed by Cu(I) yielded target polyesters with 1,2,3-triazole groups.The structure of the polymer was confirmed by spectral techniques.GPC analysis reveals that the polymers have moderate molecular weight with narrow distribution.H...展开更多
Formation of styrene carbonate (SC) by the cycloaddition of CO2 to styrene oxide (SO) catalysed by pyrrolidinopyridinium iodide (PPI) in combination with zinc halides (ZnCl2, ZnBr2 and ZnI2) was investigated. Complete...Formation of styrene carbonate (SC) by the cycloaddition of CO2 to styrene oxide (SO) catalysed by pyrrolidinopyridinium iodide (PPI) in combination with zinc halides (ZnCl2, ZnBr2 and ZnI2) was investigated. Complete conversion of the SO to SC was achieved in 3 h with 100% selectivity using 1/0.5 molar (PPI/ZnI2) catalyst ratio under mild reaction conditions i.e., 100℃ and 10 bar CO2 pressure. The synergistic effect of ZnI2 and PPI resulted in more than 7-fold increase in reaction rate than using PPI alone. The cycloaddition reaction demonstrated the first-order dependence with respect to the epoxide, CO2 and catalyst concentrations. Moreover, the kinetic and thermodynamic activation parameters of SC formation were determined using the Arrhenius and Eyring equations. The positive values of △H(42.8 kJ mol^-1) and △G(102.3 kJ mol^-1) revealed endergonic and chemically controlled nature of the reaction, whereas the large negative values of △S(-159.4 J mol^-1 K^-1) indicate a highly ordered activated complex at the transition state. The activation energy for SC formation catalyzed by PPI alone was found to be 73.2 kJ mol^-1 over a temperature range of 100-140℃, which was reduced to 46.1 kJ mol^-1 when using PPI in combination with ZnI2 as a binary catalyst. Based on the kinetic study, a synergistic acid-based reaction mechanism was proposed.展开更多
Several isoxazoline compounds were obtained by the 1,3-dipolar cycloaddition of benzonitrile oxide to 5-(R)-(l-menthyloxy)-2(5H)-furanone. The reaction condition was investigated preliminarily, the structures of thes...Several isoxazoline compounds were obtained by the 1,3-dipolar cycloaddition of benzonitrile oxide to 5-(R)-(l-menthyloxy)-2(5H)-furanone. The reaction condition was investigated preliminarily, the structures of these compounds have been established via the analysis of NMR data(involved NOEID or HMBC) and the reaction seems occurred regioselectively.展开更多
5-(1-Menthyloxy)-2(5-H)-furanone is used as s chiral dipolarophile for thermal asymmetric 1,3-dipolar cycloaddition reaction with C-phenyl-N-phenyl nitrone to give the diastereomerically pure cycloaddition product.
This paper describes the construction of hemiacetal 2, the core of pseudolaric acid A via oxidative cleavage of acetonide 6 or 7 and enolization-hemiacetalization of aldehyde 8. A plausible general mechanism for thc i...This paper describes the construction of hemiacetal 2, the core of pseudolaric acid A via oxidative cleavage of acetonide 6 or 7 and enolization-hemiacetalization of aldehyde 8. A plausible general mechanism for thc intramolecular [4+3] cycloaddition of sulfoxide 4 to adduct 3 is suggested.展开更多
Regio and stereoselective synthesis of substituted dihydrofurans were accomplished by eeric ammonium nitrate mediated oxidative cycloaddition of 1,3-dicarbonyls to β-aryl-α,β-unsaturated ketones in moderate yields.
The photoinduced intramolecular arene-olefin meta-cycloaddition was used a key step in the Synthesis of crinipellin ring skeleton.The structures of the photo products were established by1H, (13)C-NMR method.
1, 3 Dipolar cycloaddition reaction between vinyl acetate and 3-hydroxypyridiniun betaine was performed under solid-liquid phase transfer catalytic condition, This reaction has been successfully used on the synthesis ...1, 3 Dipolar cycloaddition reaction between vinyl acetate and 3-hydroxypyridiniun betaine was performed under solid-liquid phase transfer catalytic condition, This reaction has been successfully used on the synthesis of an analogue of Bao-Gong-Teng A.展开更多
The reaction mechanism of the intramolecular cycloaddition of N-3-butenyl nitrone has been investigated theoretically by using AM1 MO method and transition state theory.There are two parallel reactions leading to two ...The reaction mechanism of the intramolecular cycloaddition of N-3-butenyl nitrone has been investigated theoretically by using AM1 MO method and transition state theory.There are two parallel reactions leading to two different regioisomers.The ratio of the rate constants of these two reactions was calculated to be 124.1(at 383.75 K).The obtained results can be used to explain the high regiospecificity of the reaction product.展开更多
An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF wit...An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF with a catalytic amount of boron trifluoride. The structures of the products were determined by spectral data and the mechanism of reaction was substantiated by the imitation reaction.展开更多
文摘The synthesis of new indoloannulated thiopyranethiones is reported. The key-step is a rhodium-catalyzed [2 + 2 + 2]-cycloaddition of alkynyl-ynamides with carbon disulfide to close the pyrrole and the thiopyranethione rings simultaneously. A violet idolothiopyrane thione or a mixture of the violet and a red isomer result from [RhCl(C<sub>8</sub>H<sub>14</sub>)<sub>2</sub>]<sub>2</sub>/3BINAP catalyzed cycloadditions, the regiochemistry is controlled by the substitution pattern on the alkynyl-ynamide.
基金supported by the National Key Projects for Fundamental R&D Program of China(2016YFB0600902)the NFSC of Tianjin(16JCZDJC36700 and 14JCQNJC03000)
文摘A double active center system, namely Salen-Cu（Ⅱ）@MIL-101（Cr）, was successfully synthesized via the"ship in a bottle" approach, which acted as a bifunctional material for both capture and conversion of COin a single process. For the first time, Salen-Cu（Ⅱ）@MIL-101（Cr） catalyst was developed for the synthesis of propylene carbonate from COand propylene oxide under room temperature and ambient pressure with a yield of 87.8% over 60 h. Furthermore, the reaction mechanism was also discussed.
基金This work was supported by the NNSFC (No.29672004).
文摘1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of preparing fused heterocyclic compounds was offered by 1,3-dipolar cycloaddition reaction of silyl nitronates to 1.
基金financial support from the Program for New Century Excellent Talents in University(NCET-040270)。
文摘Two kinds of bi-functional transition metal doped mesoporous materials(Fe-HMS and Fe-MCM-41) are prepared using one-step hydrothermal method and then treated with hydrochloric acid ethanol solution.The N2 adsorption and HRTEM results show that both of Fe-HMS and Fe-MCM-41 possess mesoporous structure. The UV–vis results suggest that the Fe species are mainly located within the framework. The basicity of as-prepared samples was studied by temperature programmed desorption using CO2 as probe molecule(CO2-TPD). The catalytic performance of Fe-HMS and Fe-MCM-41 in CO2 cycloaddition largely depends on the amount of the accessible basic sites. The acid–base active sites, framework Fe and PDDA species cooperatively catalyze the CO2 cycloaddition for the production of cyclic carbonates under the condition without any co-catalyst. The conversion of epichlorohydrin(ECH) is 97.4% and the selectivity of chloropropene carbonate is 92.9% under optimal conditions. The approximate rate constant of cycloaddition reaction of CO2 with ECH under optimum reaction temperature is calculated. It is worth noting that the Fe-HMS material shows superior reusability than Fe-MCM-41. In addition, this work provides a facile way on the synthesis of bi-functional acid–base heterogeneous catalyst with outstanding catalytic performance for the fixation of CO2.
文摘facile one-step method is presented for the synthesis of indolizines in moder-ate to high yields by reaction of pyridinium, quinolinium and isoquinolinium ylideswith acrylonitrile, methyl acrylate and diethyl maleate respectively in the presenceof tetrakis-pyridino-cobalt(Ⅱ)dichromate (TPCD) in DMF.
文摘Dihydro-1H-1, 5-benzodiazepines and 1-benzoy1-2, 3-dihydro-1H-1H-1,5-benzodiazepines react with .α-carbonylkelenes, generated from 2-diazo-1,3-diphenyl-1,3-propandione or 2-diazo-1-phenyl-1,3-butandione by heating, to give 4a,5, 6, 12-letralydro- 1H,7H-1,3-oxazino[3,2-d][1,5]-benzodiazepine-1-ones,a new ring system. 2, 3-Dihydro-1H-1,5-benzodiazepines also afford,dducts of H-N bond,with a carbonylketenes, 2-aryt-1-(2-benzoyl-phenylacelyl)-4-phenyl-2,3-dihydro-1H-1,5-benzodiazepines. Addition of henzonitrile N-phenylimine,yielde in situ from the N-phenyl benzenecarbohydrazic chloride,to 2, 4-diaryl-2, 3-dihydro-1,5-benzothiazepines and 1H-1,5-benzodiazepine gave 3a, 5-diaryl-1, 3-diphenyl-3a, 4, 5, 11 tetralydro-3H-1, 2, 4-triazolo [4, 3-d][1. 5]benzothiazepine and 3H,6H-1, 2, 4 triazolo[4, 3-d][1, 5] benzodiazpine, respectively.
基金Supported by the National Natural Science Foundation of China(No.20402002)the Natural Science Foundation of Fujian Province,China (No.211J01031)+1 种基金the Project of Fujian Provincial Department of Education,China(No.JA11044)the Program for Excellent Young Researchers in Universities of Fujian Province,China(No.JA10056)
文摘1 Introduction Fullerene has received considerable attention and a great researching interest due to its unique structure and interesting properties[1―3]. Many functional groups have been introduced, often region- or stereo-selectively, for tuning the physical properties of C60and for constructing supramoleculararchitectures^[4-6].
文摘Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were characterized. Click reaction of azide and alkyne functionals catalyzed by Cu(I) yielded target polyesters with 1,2,3-triazole groups.The structure of the polymer was confirmed by spectral techniques.GPC analysis reveals that the polymers have moderate molecular weight with narrow distribution.H...
基金supported by the Engineering and Physical Science Research Council (EPSRC) funding for Sustainable Polymers (Project reference EP/L017393/1)
文摘Formation of styrene carbonate (SC) by the cycloaddition of CO2 to styrene oxide (SO) catalysed by pyrrolidinopyridinium iodide (PPI) in combination with zinc halides (ZnCl2, ZnBr2 and ZnI2) was investigated. Complete conversion of the SO to SC was achieved in 3 h with 100% selectivity using 1/0.5 molar (PPI/ZnI2) catalyst ratio under mild reaction conditions i.e., 100℃ and 10 bar CO2 pressure. The synergistic effect of ZnI2 and PPI resulted in more than 7-fold increase in reaction rate than using PPI alone. The cycloaddition reaction demonstrated the first-order dependence with respect to the epoxide, CO2 and catalyst concentrations. Moreover, the kinetic and thermodynamic activation parameters of SC formation were determined using the Arrhenius and Eyring equations. The positive values of △H(42.8 kJ mol^-1) and △G(102.3 kJ mol^-1) revealed endergonic and chemically controlled nature of the reaction, whereas the large negative values of △S(-159.4 J mol^-1 K^-1) indicate a highly ordered activated complex at the transition state. The activation energy for SC formation catalyzed by PPI alone was found to be 73.2 kJ mol^-1 over a temperature range of 100-140℃, which was reduced to 46.1 kJ mol^-1 when using PPI in combination with ZnI2 as a binary catalyst. Based on the kinetic study, a synergistic acid-based reaction mechanism was proposed.
文摘Several isoxazoline compounds were obtained by the 1,3-dipolar cycloaddition of benzonitrile oxide to 5-(R)-(l-menthyloxy)-2(5H)-furanone. The reaction condition was investigated preliminarily, the structures of these compounds have been established via the analysis of NMR data(involved NOEID or HMBC) and the reaction seems occurred regioselectively.
文摘5-(1-Menthyloxy)-2(5-H)-furanone is used as s chiral dipolarophile for thermal asymmetric 1,3-dipolar cycloaddition reaction with C-phenyl-N-phenyl nitrone to give the diastereomerically pure cycloaddition product.
基金the National Natural Science Foundation of China.
文摘This paper describes the construction of hemiacetal 2, the core of pseudolaric acid A via oxidative cleavage of acetonide 6 or 7 and enolization-hemiacetalization of aldehyde 8. A plausible general mechanism for thc intramolecular [4+3] cycloaddition of sulfoxide 4 to adduct 3 is suggested.
文摘Regio and stereoselective synthesis of substituted dihydrofurans were accomplished by eeric ammonium nitrate mediated oxidative cycloaddition of 1,3-dicarbonyls to β-aryl-α,β-unsaturated ketones in moderate yields.
文摘The photoinduced intramolecular arene-olefin meta-cycloaddition was used a key step in the Synthesis of crinipellin ring skeleton.The structures of the photo products were established by1H, (13)C-NMR method.
基金the Natural Science Foundation of Guangdong province (No. 970154).
文摘1, 3 Dipolar cycloaddition reaction between vinyl acetate and 3-hydroxypyridiniun betaine was performed under solid-liquid phase transfer catalytic condition, This reaction has been successfully used on the synthesis of an analogue of Bao-Gong-Teng A.
文摘The reaction mechanism of the intramolecular cycloaddition of N-3-butenyl nitrone has been investigated theoretically by using AM1 MO method and transition state theory.There are two parallel reactions leading to two different regioisomers.The ratio of the rate constants of these two reactions was calculated to be 124.1(at 383.75 K).The obtained results can be used to explain the high regiospecificity of the reaction product.
文摘An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF with a catalytic amount of boron trifluoride. The structures of the products were determined by spectral data and the mechanism of reaction was substantiated by the imitation reaction.
