Triflumezopyrim(TFM)is a novel mesoionic pyrido[1,2-α]pyrimidinones insecticide,which acts on nicotinic acetylcholine receptors(n ACh Rs)and has no cross-resistance with other insecticides.Herein,we firstly developed...Triflumezopyrim(TFM)is a novel mesoionic pyrido[1,2-α]pyrimidinones insecticide,which acts on nicotinic acetylcholine receptors(n ACh Rs)and has no cross-resistance with other insecticides.Herein,we firstly developed a new continuous flow approach to synthesis 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermate of TFM,coupling with esterification,condensation,and hydrolysis.All three-step reactions were optimized and transformed into a continuous synthesis mode by three micro reaction units.Compared with the batch mode,the total reaction time and overall separation yield were improved from more than 12 h and 60%to 18 min and 73.38%,respectively.The solvent consumption and waste emission were significantly reduced,which also provides an eco-friendly and efficient potential tool for the development and production of mesoionic pyrido[1,2-α]pyrimidinones insecticide.展开更多
Based on the stability results of Radix hedysari extract, an unstable compound was extracted using acidic methanol and purified by rapid chromatographic methods successfully from Radix hedysari for the first time guid...Based on the stability results of Radix hedysari extract, an unstable compound was extracted using acidic methanol and purified by rapid chromatographic methods successfully from Radix hedysari for the first time guided by HPLC analysis. Its structure was identified as formononetin 7-O-β-D-(6"-O-malonyl)-glucopyranoside by spectroscopic analyses.展开更多
Cu/SiO2 catalysts prepared by the ammonia evaporation method were applied to hydrogenation of diethyl malonate to 1,3‐propanediol. The calcination temperature played an important role in the structural evolution and ...Cu/SiO2 catalysts prepared by the ammonia evaporation method were applied to hydrogenation of diethyl malonate to 1,3‐propanediol. The calcination temperature played an important role in the structural evolution and catalytic performance of the Cu/SiO2 catalysts, which were systematically characterized by N2 adsorption‐desorption, inductively coupled plasma‐atomic emission spectros‐copy, N2O chemisorption, X‐ray diffraction, Fourier transform infrared spectroscopy, H2 tempera‐ture‐programmed reduction, transmission electron microscopy, and X‐ray photoelectron spectros‐copy. When the Cu/SiO2 catalyst was calcined at 723 K, 90.7%conversion of diethyl malonate and 32.3%selectivity of 1,3‐propanediol were achieved. Compared with Cu/SiO2 catalysts calcined at other temperatures, the enhanced catalytic performance of the Cu/SiO2 catalyst calcined at 723 K can be attributed to better dispersion of copper species, larger cupreous surface area and greater amount of copper phyllosilicate, which results in a higher ratio of Cu+/Cu0. The synergetic effect of Cu0 and Cu+is suggested to be responsible for the optimum activity.展开更多
Diethyl malonate being an initial raw material, processed with chlorination-replacement-desalination-vacuum rectification, is used to produce carbonyl diethyl malonate. An experiment for optimization determines that t...Diethyl malonate being an initial raw material, processed with chlorination-replacement-desalination-vacuum rectification, is used to produce carbonyl diethyl malonate. An experiment for optimization determines that the best reaction condition was: (1 reaction for 7 h at 10 ℃ with mole-ratio being 2.4 " 1 between chloride and raw material (diethyl malonate); (2 reaction for 4.5 h at 118 ℃ with mole-ratio being 1.2 : 1 between the anhydrous sodium acetate and intermediate I. The final product carbonyl diethyl rnalonate recovery ratio reaches up to as high as 79.12% with a purity of 96.4%, which meets the market requirement. This synthesis technique has the advantages of simple process, moderate reaction conditions, high yield and low cost, being suitable for industrial scale production.展开更多
Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported.Various trans-nitroalkenes reacted with malon...Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported.Various trans-nitroalkenes reacted with malonates affording the desired products in up to 95%yield with excellent enantioselectivities(up to 97%ee).展开更多
Ionic liquids (ILs) based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts (PTCs) for the base-promoted monoalkylatio...Ionic liquids (ILs) based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts (PTCs) for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system (IL-hase) could also be recycled after the extraction of products with ether.展开更多
A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reacti...A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reaction temperature and different bases on the yield of diethyl malonate are also discussed.展开更多
A new complex of malonic acid with lanthanum,La(Hmal)·(mal)·3H_2O,was synthesized and characterized by elemental analysis and IR spectra.The thermal decomposition process and their kinetic parameters n and E...A new complex of malonic acid with lanthanum,La(Hmal)·(mal)·3H_2O,was synthesized and characterized by elemental analysis and IR spectra.The thermal decomposition process and their kinetic parameters n and E_a were studied by means of TG and DTG.All of the intermediate and end products were determined and characterized by the mass loss in TG curve,elemental analysis and IR spectra.展开更多
A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The eff...A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The effects of some reaction parameters such as temperature. CO pressure and the concentrations of catalyst on the yields of dimethyl malonate were discussed. The kinetic data were studied and a possible reaction mechanism was proposed.展开更多
Introduction 5-Monosubstituted isopropylidene malonates arc important synthetic organic intermediates. Since isopropylidene malonate has a stronger acidity (pK;=4.57), its direct alkylation with alkyl halides usuall...Introduction 5-Monosubstituted isopropylidene malonates arc important synthetic organic intermediates. Since isopropylidene malonate has a stronger acidity (pK;=4.57), its direct alkylation with alkyl halides usually gives 5,5-disubstitutcd isopropylidene malonates.展开更多
The title complex [CaCo(C3H2O4)2(H2O)4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a...The title complex [CaCo(C3H2O4)2(H2O)4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 14,195(9), b = 7.708(5), c = 13.441(8) A, β =119.575(9)°, V = 1279.0(14) A3, Dc= 1.948 g/cm^3,μ=1.803 mm^-1, F(000) = 764 and Z = 4. The final R = 0.0245 and wR = 0.0652 for 1344 observed reflections with I 〉 2σ(I). The structure of the title complex consists of CaO8 polyhedra and CoO6 octahedra linked together by malonate ligands. The Ca(Ⅱ) cation on a twofold axis is coordinated by two water molecules and six malonate O atoms. The Co(Ⅱ) cation which lies in a centre of symmetry in an octahedral arrangement is coordinated by four malonate O atoms and two water molecules, The structure comprises alternating layers along the [101] plane, with the shortest Co-Co distance of 6.961(5)A. The whole 3D structure is maintained and stabilized by the presence of hydrogen bonds.展开更多
Radionuclide migration in aquatic environment is influenced by its sorption onto colloids/mineral oxides and the presence of organic complexing anions.With a view to understand the sorption of trivalent actinides by m...Radionuclide migration in aquatic environment is influenced by its sorption onto colloids/mineral oxides and the presence of organic complexing anions.With a view to understand the sorption of trivalent actinides by mineral oxides in presence of organic acid,in the present study,Eu(Ⅲ),malonic acid(MA)andγ-alumina are considered as representatives of trivalent actinides,low molecular weight natural occurring organic acid and aluminol sites,respectively.The influence of MA on sorption of Eu(Ⅲ)byγ-alumina was elucidated by batch sorption,spectroscopic techniques and surface complexation modeling,for the first time.Attenuated Total Reflection-Fourier Transform Infrared spectroscopic studies of MA sorbed onγ-alumina revealed the presence of two inner-sphere surface complexes.Batch sorption for binary(alumina-Eu(Ⅲ))and ternary(alumina-Eu(Ⅲ)-MA)systems were investigated as a function of p H,Eu(Ⅲ)concentration and sequential addition of Eu(Ⅲ)/MA.The p H edge for Eu(Ⅲ)sorption shifts to higher p H with increasing Eu(Ⅲ)concentration.In ternary systems,Eu(Ⅲ)sorption is significantly enhanced at p H<4.5.Eu(Ⅲ)speciation onγ-alumina is independent of addition sequence of Eu(Ⅲ)/MA.Time resolved fluorescence spectroscopy of Eu(Ⅲ)sorbed onγ-alumina exhibited two surface species,≡XOEu^2+and(≡YO)2 Eu^(+).The enhancement in I 616/I 592 and lifetime for ternary systems,as compared to binary system,at low p H,indicates the participation of Eu-MA complexes in the formation of surface species in ternary systems.The diffuse layer model has been employed to successfully model the experimental sorption profiles of binary and ternary systems,using code FITEQL 4.0,by considering the surface species identified by spectroscopic techniques.展开更多
The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
It has been found that microwave assisted decarboxylation of malonic acid derivatives can be achieved under solvent-free and catalyst free conditions. This new method produces the corresponding carboxylic acid in a pu...It has been found that microwave assisted decarboxylation of malonic acid derivatives can be achieved under solvent-free and catalyst free conditions. This new method produces the corresponding carboxylic acid in a pure manner and with a high yield in a very short reaction time: 3 - 10 min. In general terms, the condition under which this reaction is carried out accelerates the decarboxylation significantly of a series of disubstituted malonic acid derivatives, and makes this new process efficient, easy and environmentally friendly.展开更多
Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol a...Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol at moderate temperature. These compounds were characterized by elemental analysis, UV-VIS, IR spectroscopies and powder X-ray diffraction analyses. Compound (<strong>1</strong>) melts at higher temperature (202°C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">°</span>C). The IR spectra showed typical vibrations related to C=N and C=C, characteristic of pyrazolyl and pyridine ligands.展开更多
An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temp...An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature.展开更多
A series of malonate derivatives-calix[4]arene conjugates were synthesized through Knoevenagel condensation reaction between formyl-tetrapropoxycalix[4]arene and malonate derivatives. The structures of the resulting m...A series of malonate derivatives-calix[4]arene conjugates were synthesized through Knoevenagel condensation reaction between formyl-tetrapropoxycalix[4]arene and malonate derivatives. The structures of the resulting malonate derivative functionalized calix[4]arenes were characterized by NMR spectroscopy, mass spectrometry and even single crystal X-ray diffraction analysis.展开更多
基金the National Key Research and Development Program of China(Nos.2023YFD1700303,2022YFD17800)National Natural Science Foundation of China(Nos.21878088,21476077)for financial support。
文摘Triflumezopyrim(TFM)is a novel mesoionic pyrido[1,2-α]pyrimidinones insecticide,which acts on nicotinic acetylcholine receptors(n ACh Rs)and has no cross-resistance with other insecticides.Herein,we firstly developed a new continuous flow approach to synthesis 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermate of TFM,coupling with esterification,condensation,and hydrolysis.All three-step reactions were optimized and transformed into a continuous synthesis mode by three micro reaction units.Compared with the batch mode,the total reaction time and overall separation yield were improved from more than 12 h and 60%to 18 min and 73.38%,respectively.The solvent consumption and waste emission were significantly reduced,which also provides an eco-friendly and efficient potential tool for the development and production of mesoionic pyrido[1,2-α]pyrimidinones insecticide.
基金National Natural Science Foundation of China (Grant No.20432030 and 20872006).
文摘Based on the stability results of Radix hedysari extract, an unstable compound was extracted using acidic methanol and purified by rapid chromatographic methods successfully from Radix hedysari for the first time guided by HPLC analysis. Its structure was identified as formononetin 7-O-β-D-(6"-O-malonyl)-glucopyranoside by spectroscopic analyses.
文摘Cu/SiO2 catalysts prepared by the ammonia evaporation method were applied to hydrogenation of diethyl malonate to 1,3‐propanediol. The calcination temperature played an important role in the structural evolution and catalytic performance of the Cu/SiO2 catalysts, which were systematically characterized by N2 adsorption‐desorption, inductively coupled plasma‐atomic emission spectros‐copy, N2O chemisorption, X‐ray diffraction, Fourier transform infrared spectroscopy, H2 tempera‐ture‐programmed reduction, transmission electron microscopy, and X‐ray photoelectron spectros‐copy. When the Cu/SiO2 catalyst was calcined at 723 K, 90.7%conversion of diethyl malonate and 32.3%selectivity of 1,3‐propanediol were achieved. Compared with Cu/SiO2 catalysts calcined at other temperatures, the enhanced catalytic performance of the Cu/SiO2 catalyst calcined at 723 K can be attributed to better dispersion of copper species, larger cupreous surface area and greater amount of copper phyllosilicate, which results in a higher ratio of Cu+/Cu0. The synergetic effect of Cu0 and Cu+is suggested to be responsible for the optimum activity.
基金Supported by the Innovation Fund for Technology Based Firms(10C26224212340)
文摘Diethyl malonate being an initial raw material, processed with chlorination-replacement-desalination-vacuum rectification, is used to produce carbonyl diethyl malonate. An experiment for optimization determines that the best reaction condition was: (1 reaction for 7 h at 10 ℃ with mole-ratio being 2.4 " 1 between chloride and raw material (diethyl malonate); (2 reaction for 4.5 h at 118 ℃ with mole-ratio being 1.2 : 1 between the anhydrous sodium acetate and intermediate I. The final product carbonyl diethyl rnalonate recovery ratio reaches up to as high as 79.12% with a purity of 96.4%, which meets the market requirement. This synthesis technique has the advantages of simple process, moderate reaction conditions, high yield and low cost, being suitable for industrial scale production.
基金support from Natural Science Foundation of China(No.20772097)Sichuan Provincial Science Foundation for Outstanding Youth(No.05ZQ026-008)Key Project of the Education Department of Sichuan Province(No.2006A081).
文摘Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported.Various trans-nitroalkenes reacted with malonates affording the desired products in up to 95%yield with excellent enantioselectivities(up to 97%ee).
文摘Ionic liquids (ILs) based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts (PTCs) for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system (IL-hase) could also be recycled after the extraction of products with ether.
文摘A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reaction temperature and different bases on the yield of diethyl malonate are also discussed.
基金Project supported by the National Natural Science Foundation of China
文摘A new complex of malonic acid with lanthanum,La(Hmal)·(mal)·3H_2O,was synthesized and characterized by elemental analysis and IR spectra.The thermal decomposition process and their kinetic parameters n and E_a were studied by means of TG and DTG.All of the intermediate and end products were determined and characterized by the mass loss in TG curve,elemental analysis and IR spectra.
文摘A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The effects of some reaction parameters such as temperature. CO pressure and the concentrations of catalyst on the yields of dimethyl malonate were discussed. The kinetic data were studied and a possible reaction mechanism was proposed.
基金Supported by the National Natural Science Foundation of Chinathe Basic Research Foundation of Zhejian Educational Commission.
文摘Introduction 5-Monosubstituted isopropylidene malonates arc important synthetic organic intermediates. Since isopropylidene malonate has a stronger acidity (pK;=4.57), its direct alkylation with alkyl halides usually gives 5,5-disubstitutcd isopropylidene malonates.
基金This work was supported by the Education Office of Anhui Province (No. 200161) and the Hubei Key Laboratory of Novel Chemical Reactor and Green Chemical Technology (No. RCT2004011)
文摘The title complex [CaCo(C3H2O4)2(H2O)4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 14,195(9), b = 7.708(5), c = 13.441(8) A, β =119.575(9)°, V = 1279.0(14) A3, Dc= 1.948 g/cm^3,μ=1.803 mm^-1, F(000) = 764 and Z = 4. The final R = 0.0245 and wR = 0.0652 for 1344 observed reflections with I 〉 2σ(I). The structure of the title complex consists of CaO8 polyhedra and CoO6 octahedra linked together by malonate ligands. The Ca(Ⅱ) cation on a twofold axis is coordinated by two water molecules and six malonate O atoms. The Co(Ⅱ) cation which lies in a centre of symmetry in an octahedral arrangement is coordinated by four malonate O atoms and two water molecules, The structure comprises alternating layers along the [101] plane, with the shortest Co-Co distance of 6.961(5)A. The whole 3D structure is maintained and stabilized by the presence of hydrogen bonds.
文摘Radionuclide migration in aquatic environment is influenced by its sorption onto colloids/mineral oxides and the presence of organic complexing anions.With a view to understand the sorption of trivalent actinides by mineral oxides in presence of organic acid,in the present study,Eu(Ⅲ),malonic acid(MA)andγ-alumina are considered as representatives of trivalent actinides,low molecular weight natural occurring organic acid and aluminol sites,respectively.The influence of MA on sorption of Eu(Ⅲ)byγ-alumina was elucidated by batch sorption,spectroscopic techniques and surface complexation modeling,for the first time.Attenuated Total Reflection-Fourier Transform Infrared spectroscopic studies of MA sorbed onγ-alumina revealed the presence of two inner-sphere surface complexes.Batch sorption for binary(alumina-Eu(Ⅲ))and ternary(alumina-Eu(Ⅲ)-MA)systems were investigated as a function of p H,Eu(Ⅲ)concentration and sequential addition of Eu(Ⅲ)/MA.The p H edge for Eu(Ⅲ)sorption shifts to higher p H with increasing Eu(Ⅲ)concentration.In ternary systems,Eu(Ⅲ)sorption is significantly enhanced at p H<4.5.Eu(Ⅲ)speciation onγ-alumina is independent of addition sequence of Eu(Ⅲ)/MA.Time resolved fluorescence spectroscopy of Eu(Ⅲ)sorbed onγ-alumina exhibited two surface species,≡XOEu^2+and(≡YO)2 Eu^(+).The enhancement in I 616/I 592 and lifetime for ternary systems,as compared to binary system,at low p H,indicates the participation of Eu-MA complexes in the formation of surface species in ternary systems.The diffuse layer model has been employed to successfully model the experimental sorption profiles of binary and ternary systems,using code FITEQL 4.0,by considering the surface species identified by spectroscopic techniques.
文摘The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
文摘It has been found that microwave assisted decarboxylation of malonic acid derivatives can be achieved under solvent-free and catalyst free conditions. This new method produces the corresponding carboxylic acid in a pure manner and with a high yield in a very short reaction time: 3 - 10 min. In general terms, the condition under which this reaction is carried out accelerates the decarboxylation significantly of a series of disubstituted malonic acid derivatives, and makes this new process efficient, easy and environmentally friendly.
文摘Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol at moderate temperature. These compounds were characterized by elemental analysis, UV-VIS, IR spectroscopies and powder X-ray diffraction analyses. Compound (<strong>1</strong>) melts at higher temperature (202°C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">°</span>C). The IR spectra showed typical vibrations related to C=N and C=C, characteristic of pyrazolyl and pyridine ligands.
基金We appreciate the National Natural Science Foundation of China (No. 20962018, 20862015, 20762009 and 20562011) for supporting this research.
文摘An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature.
基金Financial support from the National Natural Science Foundation of China (No. 21371177) is acknowledged
文摘A series of malonate derivatives-calix[4]arene conjugates were synthesized through Knoevenagel condensation reaction between formyl-tetrapropoxycalix[4]arene and malonate derivatives. The structures of the resulting malonate derivative functionalized calix[4]arenes were characterized by NMR spectroscopy, mass spectrometry and even single crystal X-ray diffraction analysis.