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Efficient continuous synthesis of 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermediate of Triflumezopyrim,coupling with esterification-condensation-hydrolysis
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作者 Yuexiang Liu Xiangqiao Yang +6 位作者 Tong Lin Guantian Yang Xiaoyong Xu Bubing Zeng Zhong Li Weiping Zhu Xuhong Qian 《Chinese Chemical Letters》 2025年第1期234-238,共5页
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
关键词 Triflumezopyrim(TFM) 2-[3-(Trifluoromethyl)phenyl]malonic acid Continuous flow synthesis MICRO-REACTOR
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Isolation and structural elucidation of an unstable isoflavonoid glycoside malonate from Radix hedysari 被引量:1
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作者 刘毅 赵玉英 +1 位作者 陈虎彪 张庆英 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第2期100-103,共4页
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
关键词 Radix hedysari Formononetin 7-O-β-D-(6"-O-malonyl)-glucopyranoside Isoflavonoid glycoside malonate
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Highly active Cu/SiO_2 catalysts for hydrogenation of diethyl malonate to 1,3-propanediol 被引量:7
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作者 丁同梅 田恒水 +2 位作者 刘纪昌 吴文滨 余锦涛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期484-493,共10页
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
关键词 COPPER SILICA Diethyl malonate HYDROGENATION 1 3-PROPANEDIOL Calcination temperature
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Malone顺性灌肠治疗神经性大便失禁 被引量:4
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作者 孙小兵 李金良 +2 位作者 陈雨历 张敏刚 陈维秀 《中国脊柱脊髓杂志》 CAS CSCD 2002年第5期383-384,共2页
目的:评价Malone顺性灌肠治疗神经性大便失禁的临床疗效。方法:1998年10月~1999年12月间对14例伴有大便失禁的脊髓拴系综合征患者(4~13岁)施行Malone手术,术后间断经阑尾造瘘口插管灌肠。对手术效果及肛门功能分别进行量化评分。结果... 目的:评价Malone顺性灌肠治疗神经性大便失禁的临床疗效。方法:1998年10月~1999年12月间对14例伴有大便失禁的脊髓拴系综合征患者(4~13岁)施行Malone手术,术后间断经阑尾造瘘口插管灌肠。对手术效果及肛门功能分别进行量化评分。结果:14例随访时间6个月~1年,2例造瘘口闭塞。余12例手术效果评分为21.4±1.3;肛门功能临床主观评分5郾05±0郾76,较术前(1郾23±0.64)明显增加(P<0郾01),其中优9例,良3例,差2例。结论:Malone顺性灌肠是治疗神经性大便失禁的有效方法,可明显提高患儿的生活质量。 展开更多
关键词 malone顺性灌肠 治疗 神经性大便失禁 脊髓拴系统合征 儿童 疗效分析
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Research of Technique for Synthesizing Carbonyl Diethyl Malonate
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作者 GUI Houying DONG Liuyu ZHOU Qiuming HU Xinming 《Wuhan University Journal of Natural Sciences》 CAS 2011年第3期271-276,共6页
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
关键词 diethyl malonate CHLORINATION REPLACEMENT DESALINATION RECTIFICATION carbonyl diethyl malonate
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可控性Malone顺行灌肠的护理体会
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作者 任志东 《中国药物与临床》 CAS 2017年第7期1092-1093,共2页
大便失禁和顽固性便秘是小儿肛门直肠畸形术后常见的问题,至今仍是一个难以解决的课题。1990年Malone等[1]提出应用顺行灌肠的方法进行肠道管理,可有效解决失禁及便秘的问题。我们根据2013年8月至2016年8月15例行Malone顺行灌肠(malone... 大便失禁和顽固性便秘是小儿肛门直肠畸形术后常见的问题,至今仍是一个难以解决的课题。1990年Malone等[1]提出应用顺行灌肠的方法进行肠道管理,可有效解决失禁及便秘的问题。我们根据2013年8月至2016年8月15例行Malone顺行灌肠(malone antegrade continence enema,MACE)患儿的护理经验,讨论护理对于Malone顺行灌肠的重要性。 展开更多
关键词 malone 肛门直肠畸形 顽固性便秘 肛门成形术 ENEMA 导尿管 大便失禁 插管困难 巨直肠 术前健康教育
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Novel chiral thioureas for highly enantioselective Michael reactions of malonates to nitroalkenes 被引量:2
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作者 Li Jun Yan Quan Zhong Liu Xue Lian Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第3期310-313,共4页
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
关键词 Michael addition Thiourea Enantioselectivities Nitroalkene and malonate
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Ionic liquids as efficient phase-transfer catalysts for the solid base-promoted monoalkylation of diethyl malonate 被引量:1
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作者 Hui Sun Juan Li Xiao Chen Cai Dong Jiang Li Yi Dai 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第3期279-282,共4页
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
关键词 Ionic liquids Phase-transfer catalysis Diethyl malonate ALKYLATION
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A Novel Synthesis of Diethyl Malonate 被引量:1
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作者 Song, WH Jiang, XZ 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第12期1035-1036,共2页
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
关键词 diethyl malonate phase transfer agent CARBONYLATION
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Synthesis,Characterization and Thermal Decomposition Behaviour of Tri-aquo Lanthanum(Ⅲ)Malonate Bimalonate
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作者 薛文梅 杨汝栋 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第3期216-219,共4页
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
关键词 LANTHANUM malonic acid Complex Thermal decomposition Kinetic parameter
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A Novel Synthesis of Dimethyl Malonate by Carbonylation of Methyl Chloroacetate Catalyzed by Cobalt Complex
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作者 Wei Hong SONG Xuan Zhen JIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第3期207-210,共4页
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
关键词 Dimethyl malonate cobalt complex CARBONYLATION reaction mechanism
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A Facile Synthesis of 5-Monosubstituted Isopropylidene Malonates
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作者 Huang Xian and Wu Jlnlong (Department of Chemistry, Hanyzhou University, Hangzhou) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期399-401,共3页
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
关键词 Isopropylidene malonate CONDENSATION REDUCTION Phase transfer catalysis
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Synthesis and Crystal Structure of a Novel Hetero-bimetallic Complex with a Three-dimensional Network Structure: Bis(malonato)tetra(aqua)calcum(II)cobalt(II)
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作者 傅绪成 聂丽 +2 位作者 张强 李明田 王小燕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第12期1449-1452,共4页
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
关键词 calcium COBALT crystal structure malonATE
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Solid Phase Synthesis of 4(1H)Quinolones from Resin-Bound Cyclic Malonic Ester
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作者 Zhan Xiang LIU Wan Li CHEN Xian HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第3期193-194,共2页
The solid phase synthesis of 4 (1H) quinolones has been reported.
关键词 4(1H) Quinolone Meldrum's acid solid phase synthesis cyclic malonic ester.
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Probing and understanding interaction of Eu(Ⅲ)withγ-alumina in presenceof malonic acid
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作者 Madhuri A Patel Aishwarya Soumitra Kar +1 位作者 Vaibhavi V Raut B.S.Tomar 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第2期181-192,共12页
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
关键词 malonic acid Eu(Ⅲ) Γ-ALUMINA SORPTION ATR-FTIR TRFS Surface complexation modeling
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Condensation of Aromatic Aldehydes with Isopropylidene Malonate or 5,5-Dimethyl-1,3-cyclohexanedion without Catalyst
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作者 Dai Qing SHI Yuan GAO +2 位作者 Lai Laong MU Zai Sheng LU Gui Yuan DAI(Department of Chemistry, Xuzhou Normal University, Xuzhou 221009) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期755-758,共4页
The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
关键词 IR HNMR Cl ppm Condensation of Aromatic Aldehydes with Isopropylidene malonate or 5 5-Dimethyl-1 3-cyclohexanedione without Catalyst KBr
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Solvent- and Catalyst-Free Microwave-Assisted Decarboxylation of Malonic Acid Derivatives
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作者 Fanny Araceli Cabrera-Rivera Luis Gabriel Hernández-Vázquez +2 位作者 Patricia Flores-Sánchez Maria Durán-Galván Jaime Escalante 《Green and Sustainable Chemistry》 2017年第4期270-280,共11页
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
关键词 Microwave DECARBOXYLATION malonic Acid DERIVATIVES SOLVENT-FREE CATALYST-FREE Green Chemistry
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Syntheses and Characterization of Two Novel Copper(II) Malonate Complexes Functionalized with 3,3’-Bis(pyrazolyl)pentane and 4,4’-Trimethylenedipyridine
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作者 Alvine Loris Djoumbissie Alain Clovis Tayo Djampouo +4 位作者 Tanyi Rogers Fomuta Giscard Doungmo Golngar Djimassingar Alain Charly Tagne Kuate Jean Ngoune 《Open Journal of Inorganic Chemistry》 2021年第2期43-53,共11页
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&#176;C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">&#176;</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
关键词 COPPER malonATE 3 3’-Bis(pyrazolyl)pentane 4 4’-Trimethylenedipyridine UV-Vis IR Powder X-Ray Diffraction
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Organocatalyzed Highly Efficient Michael Addition of Malonate Derivatives to α,β-Unsaturated Ketones Using Chiral Schiff Bases
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作者 Yonghai Hui Jianzhong Zhang +1 位作者 Wanfu Sun Zhengfeng Xie 《Journal of Chemistry and Chemical Engineering》 2011年第9期847-853,共7页
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
关键词 α β-unsaturated ketones cyanoacetate malonATE Michael addition Schiffbase.
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Synthesis and structures of malonate derivative-calix [4] arene conjugates
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作者 Wen-Jing Hu Ming-Liang Ma +3 位作者 Yahu A.Liu Jiu-Sheng Li Biao Jiang Ke Wen 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第7期914-917,共4页
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
关键词 arene malonate derivatives Knoevenagel condensation reaction
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