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The regulation of ferrocene-based catalysts on heat transfer in highpressure combustion of ammonium perchlorate/hydroxyl-terminated polybutadiene/aluminum composite propellants 被引量:1
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作者 Jinchao Han Songqi Hu Linlin Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期174-186,共13页
The regulation of the burning rate pressure exponent for the ammonium perchlorate/hydroxylterminated polybutadiene/aluminum(AP/HTPB/Al)composite propellants under high pressures is a crucial step for its application i... The regulation of the burning rate pressure exponent for the ammonium perchlorate/hydroxylterminated polybutadiene/aluminum(AP/HTPB/Al)composite propellants under high pressures is a crucial step for its application in high-pressure solid rocket motors.In this work,the combustion characteristics of AP/HTPB/Al composite propellants containing ferrocene-based catalysts were investigated,including the burning rate,thermal behavior,the local heat transfer,and temperature profile in the range of 7-28 MPa.The results showed that the exponent breaks were still observed in the propellants after the addition of positive catalysts(Ce-Fc-MOF),the burning rate inhibitor((Ferrocenylmethyl)trimethylammonium bromide,Fc Br)and the mixture of Fc Br/catocene(GFP).However,the characteristic pressure has increased,and the exponent decreased from 1.14 to 0.66,0.55,and 0.48 when the addition of Ce-FcMOF,Fc Br and Fc Br/GFP in the propellants.In addition,the temperature in the first decomposition stage was increased by 7.50℃ and 11.40℃ for the AP/Fc Br mixture and the AP/Fc Br/GFP mixture,respectively,compared to the pure AP.On the other hand,the temperature in the second decomposition stage decreased by 48.30℃ and 81.70℃ for AP/Fc Br and AP/Fc Br/GFP mixtures,respectively.It was also found that Fc Br might generate ammonia to cover the AP surface.In this case,a reaction between the methyl in Fc Br and perchloric acid caused more ammonia to appear at the AP surface,resulting in the suppression of ammonia desorption.In addition,the coarse AP particles on the quenched surface were of a concave shape relative to the binder matrix under low and high pressures when the catalysts were added.In the process,the decline at the AP/HTPB interface was only exhibited in the propellant with the addition of Ce-Fc-MOF.The ratio of the gas-phase temperature gradient of the propellants containing catalysts was reduced significantly below and above the characteristic pressure,rather than 3.6 times of the difference in the blank propellant.Overall,the obtained results demonstrated that the pressure exponent could be effectively regulated and controlled by adjusting the propellant local heat and mass transfer under high and low pressures. 展开更多
关键词 AP/HTPB/Al propellants Heat transfer High-pressure combustion Ferrocene-based catalysts Pressure exponent
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Catalytic Oxidation of Cyclohexene to Adipic Acid with a Reaction-Controlled Phase-Transfer Catalyst 被引量:13
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作者 GUO Minglin (College of Materials and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300160, China) 《催化学报》 SCIE CAS CSCD 北大核心 2003年第7期483-484,共2页
关键词 催化氧化反应 环己烯 脂肪酸 反应控制 相转移催化剂 癸钨酸盐 十二钨磷酸盐 有机合成
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A facile and convenient method for synthesis of alkyl thiocyanates under homogeneous phase transfer catalyst conditions 被引量:3
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作者 Ali Reza Kiasat Rashid Badri Soheil Sayyahi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1301-1304,共4页
A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst. The reactions occur i... A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification. 展开更多
关键词 Alkyl thiocyanate Alkyl halide Tetrabutylammonium bromide phase transfer catalyst Synthesis of alkyl thiocyanates
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Nuclephilic ring opening of epoxides promoted by multi-site phase-transfer catalyst:An efficient and eco-friendly route to synthesis of β-hydroxythiocyanate 被引量:2
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作者 Ali Reza Kiasat Roya Mirzajani +1 位作者 Haji Shalbaf Tahereh Tabatabaei 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1025-1029,共5页
A highly effective and mild protocol for ring opening of epoxides with NH4SCN in the presence of catalytic amount of a multi- site phase-transfer catalyst, α,α',α"-N-hexakis(triethylammoniummethylene chloride)-... A highly effective and mild protocol for ring opening of epoxides with NH4SCN in the presence of catalytic amount of a multi- site phase-transfer catalyst, α,α',α"-N-hexakis(triethylammoniummethylene chloride)-melamine, is developed. A variety of ^-hydroxy thiocyanates as important intermediates in agricultural and pharmaceutical chemistry were obtained in high yields with excellent regioselectivity and in short reaction times. 2009 Ali Reza Kiasat. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Multi-site phase-transfer catalyst β-Hydroxythiocyanate Thiocyanohydrin EPOXIDE Ring opening Regioselectivity
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Syntheses of α-Hydroxyarylacetic Acids in the Presence of Different Phase Transfer Catalysts Under Sonication 被引量:1
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作者 XU Wei-liang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第2期175-177,共3页
The syntheses of α-hydroxyarylacetic acids with a good yield in the presence of different phase transfer catalysts (PTC) under sonication were studied. The results obtained are superior to those by other similar met... The syntheses of α-hydroxyarylacetic acids with a good yield in the presence of different phase transfer catalysts (PTC) under sonication were studied. The results obtained are superior to those by other similar methods. The data show that β-cyclodextrin (β-CD) is more efficient than other PTC. The preliminary reaction conditions are also discussed. 展开更多
关键词 α-Hydroxyarylacetic acid phase transfer catalyst Sonication
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A New Reaction-controlled Phase-transfer Catalyst System 被引量:1
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作者 MingQiangLI XiGaoJIAN GuiMeiWANG YanYU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第3期350-352,共3页
A new reaction-controlled phase-transfer catalyst system was designed and synthesized. In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxida... A new reaction-controlled phase-transfer catalyst system was designed and synthesized. In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxidant. The conversion of H2O2 was 100% and the yield of cyclohexene oxide was 87.1% based on cyclohexene. Infrared spectra showed that both fresh catalyst and the recovered catalyst do have completely same absorption peak, indicating the structure of catalyst is very stability and can be recycled. 展开更多
关键词 Reaction-controlled phase-transfer catalyst CYCLOHEXENE epoxidation.
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Interphase Mass Transfer in G-L-S Magnetically Stabilized Bed with Amorphous Alloy SRNA-4 Catalyst 被引量:1
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作者 李韡 宗保宁 +2 位作者 李晓芳 孟祥坤 张金利 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第6X期734-739,共6页
Gas-liquid (G-L) and liquid-solid (L-S) mass transfer coefficients were characterized in a gas-liquid-solid (G-L-S) three-phase magnetically stabilized bed (MSB) using amorphous alloy SRNA-4 as the solid phase. Effect... Gas-liquid (G-L) and liquid-solid (L-S) mass transfer coefficients were characterized in a gas-liquid-solid (G-L-S) three-phase magnetically stabilized bed (MSB) using amorphous alloy SRNA-4 as the solid phase. Effects such as superficial liquid velocity, superficial gas velocity, magnetic strength, liquid viscosity, and particle size were investigated. Experimental results indicated that the G-L volumetric mass transfer coefficients (KLa) increased along with the magnetic strength, superficial gas and liquid velocities. Proper increase of liquid viscosity promoted KLa only in the range of lower liquid viscosity. The external magnetic field made L-S mass transfer coefficients (Ks) in the G-L-S MSB lower than those of conventional fluidized beds. Ks in the MSB almost kept constant as the su- perficial liquid velocity and superficial gas velocity increased and decreased with the liquid viscosity and surface tension, while increased with the particle size Ks showed uniform axial and radial distributions except of small de- creases close to the wall. Dimensionless correlations were established to estimate KLa and Ks of the MSB with SRNA-4 catalysts , which showed the average error of 5.4% and 2.5% respectively. 展开更多
关键词 magnetically stabilized bed GAS-LIQUID MASS transfer liquid-solid MASS transfer SRNA-4 catalyst
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Structural engineering of Fe single-atom oxygen reduction catalyst with high site density and improved mass transfer
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作者 Jiawen Wu Yuanzhi Zhu +3 位作者 An Cai Xiaobin Fan Wenchao Peng Yang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期634-644,共11页
Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges re... Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges remain in their low site density and unsatisfactory mass transfer structure.Herein,we present a structural engineering approach employing a soft-template coating strategy to fabricate a hollow and hierarchically porous N-doped carbon framework anchored with atomically dispersed Fe sites(FeNCh) as an efficient ORR catalyst.The combination of hierarchical porosity and high exterior surface area is proven crucial for exposing more active sites,which gives rise to a remarkable ORR performance with a half-wave potential of 0.902 V in 0.1 m KOH and 0.814 V in 0.1 m HClO_(4),significantly outperforming its counterpart with solid structure and dominance of micropores(FeNC-s).The mass transfer property is revealed by in-situ electrochemical impedance spectroscopy(EIS) measurement.The distribution of relaxation time(DRT) analysis is further introduced to deconvolve the kinetic and mass transport processes,which demonstrates an alleviated mass transport resistance for FeNC-h,validating the effectiveness of structural engineering.This work not only provides an effective structural engineering approach but also contributes to the comprehensive mass transfer evaluation on advanced electrocatalyst for energy conversion applications. 展开更多
关键词 Single-atom catalysts Oxygen reduction reaction Structural engineering Active site density Mass transfer Zinc-air batteries
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A Cu-Pd alloy catalyst with partial phase separation for the electrochemical CO_(2) reduction reaction
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作者 Gyeong Ho Han Jung Yong Seo +4 位作者 Minji Kang Myung-gi Seo Youngheon Choi Soo Young Kim Sang Hyun Ahn 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期8-15,I0001,共9页
Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single prod... Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single product.Herein,we report a simple fabrication method for a Cu-Pd alloy catalyst for use in a membrane electrode assembly(MEA)-based CO_(2) electrolyzer for the electrochemical CO_(2) reduction reaction(ECRR)with high selectivity for CO production.When the composition of the Cu-Pd alloy catalyst was fabricated at 6:4,the selectivity for CO increased and the production of multi-carbon compounds and hydrogen is suppressed.Introducing a Cu-Pd alloy catalyst with 6:4 ratio as the cathode of the MEAbased CO_(2) electrolyzer showed a CO faradaic efficiency of 92.8%at 2.4 V_(cell).We assumed that these results contributed from the crystal planes on the surface of the Cu-Pd alloy.The phases of the Cu-Pd alloy catalyst were partially separated through annealing to fabricate a catalyst with high selectivity for CO at low voltage and C_(2)H_4 at high voltage.The results of CO-stripping testing confirmed that when Cu partially separates from the lattice of the Cu-Pd alloy,the desorption of~*CO is suppressed,suggesting that C-C coupling reaction is favored. 展开更多
关键词 Cu-Pd catalyst ELECTRODEPOSITION Electrochemical carbon dioxide reduction Partial phase separation Membrane electrode assembly-based electrolyzer
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Selective oxidation of cyclopentene with H2O2 by using H3PW12O40 and TBAB as a phase transfer catalyst 被引量:3
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作者 Yaling Luo Changjun Liu +3 位作者 Hairong Yue Siyang Tang Yingming Zhu Bin Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1851-1856,共6页
The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantl... The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantly improved the oxidation selectivity of cyclopentene. The effects of the reaction conditions on the conversion of cyclopentene were investigated in detail. The optimal reaction conditions are as follows: the H3PW12O40 to TBAB molar ratio, 1:1–1:3;H3PW12O40 to cyclopentene molar ratio,0.54:100–0.64:100;and molar ratio of H2O2 to cyclopentene, 1.6:1. The conversion reached to 59.8% in 4h at 35.0 ℃, while the selectivity of glutaraldehyde was 38.0% and the selectivity of 1,2-cyclopentanediol was 55.6%. In addition, a route for oxidation of cyclopentene by aqueous H2O2 using a heteropoly acid and quaternary ammonium salt as a phase transfer catalyst was proposed. 展开更多
关键词 GLUTARALDEHYDE CYCLOPENTENE oxidation phase-transfer HETEROPOLY acid
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Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst 被引量:5
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作者 Zhi Huan Weng Jin Yan Wang Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期936-938,共3页
A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the pr... A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability. 展开更多
关键词 HETEROPOLYTUNGSTATE Reaction-controlled phase-transfer Benzyl alcohol BENZALDEHYDE Hydrogen peroxide
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The Action Mechanism of Phase Transfer Catalyst in the Oxidation of Toluene by Mn^(3+) in 40% H_2SO_4
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作者 胡万里 周定 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第2期41-44,共4页
TheActionMechanismofPhaseTransferCatalystintheOxidationofToluenebyMn^(3+)in40%H_2SO_4¥(胡万里)(周定)HUWanli;ZHOUDi... TheActionMechanismofPhaseTransferCatalystintheOxidationofToluenebyMn^(3+)in40%H_2SO_4¥(胡万里)(周定)HUWanli;ZHOUDing(Dept.ofApplied?.. 展开更多
关键词 ss:Action MECHANISM Mn ̄(3+) TOLUENE phase transfer catalyst
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The Reactions Between Halides and Alcohols in the Presence of Phase Transfer Catalysts Without Any Base
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作者 JIANG Yu-lin YUAN Yun-cheng and WU Bao-qing (School of Chemical Engineering, Dalian University of Technofogy, Dalian, 116012) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第2期156-158,共3页
TheReactionsBetweenHalidesandAlcoholsinthePresenceofPhaseTransferCatalystsWithoutAnyBaseJIANGYu-lin;YUANYun-... TheReactionsBetweenHalidesandAlcoholsinthePresenceofPhaseTransferCatalystsWithoutAnyBaseJIANGYu-lin;YUANYun-cheng;andWUBao-qi... 展开更多
关键词 Direct etherification phase transfer catalyst HALIDES ALCOHOLS
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Synthesis of α-Aminoarylacetic Acids in the Presence of Phase Transfer Catalysts
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作者 Wei Liang XU You Fang CHEN Fei Long WU(Basic Course Division, Zhejiang Agricultural University, Hangzhou 310029) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第10期813-816,共4页
Synthesis of aminoarylacetic acids with good yield in the presence of phase transfercatalyst (PTC) under sonication has been studied. Results obtained are superior to those by othersimilar methods. The data show that ... Synthesis of aminoarylacetic acids with good yield in the presence of phase transfercatalyst (PTC) under sonication has been studied. Results obtained are superior to those by othersimilar methods. The data show that cyclodextrin (5 -CD) is a more efficient catalyst thanother PTC. Optimum reaction conditions and a preliminary mechanism are also discussed. 展开更多
关键词 α-Aminoarylacetic acid phase transfer catalyst sonication.
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A Convenient Synthesis of Aromatic Fluoride by Thermal Stable Pyridinium Phase-transfer Catalyst
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作者 Ying Hong ZHU Hui LOU +2 位作者 Ping LU Jia Geng LIU Xiao Ming ZHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第10期919-920,共2页
Using 4-Dialkylaminopyridinium salt as a thermal stable phase-transfer catalyst (PTC), the excellent results were obtained in the halogen-exchange fluorination.
关键词 4-dialkylaminopyridinium salt phase-transfer catalyst FLUORINATION
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Development of Antioxidants Synthesized by Phase Transfer Catalysts for Lubricating Oil
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作者 Noura El Mehbad 《Journal of Surface Engineered Materials and Advanced Technology》 2014年第1期29-32,共4页
The oxidation stability of lubricating oil has a critical influence on the oil performance during service. In this paper, dibenzyl-S-phenyl thioglyconitrile and other derivatives were prepared by phase transfer cataly... The oxidation stability of lubricating oil has a critical influence on the oil performance during service. In this paper, dibenzyl-S-phenyl thioglyconitrile and other derivatives were prepared by phase transfer catalysts and investigated as antioxidants. These compounds were added to oil in different concentrations. The antioxidants activities of different dosages were evaluated and the mechanism was suggested according to micelle and its thermodynamics. The oxidation of the oil has been carried out at different time intervals. The degradation of the oil has been monitored by total acid formation. Oxidation stability of lube oil was largely affected by sulphur and concentration of aromatic hydrocarbons in oil, with the increased sulphur content increasing oxidation stability. The prepared compounds gave higher oxidation stability than imported compound (IRCANOX L 135-CIBA). 展开更多
关键词 phase transfer catalystS Lube OIL ANTIOXIDANTS
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Novel Bis-(N-alkyl-N ,N-dimethyl-ammonium) Polyethyleneglycol Ether Salts as Phase Transfer Catalysts in the Condensation of l,4-Diacetyl-2,5-piperazinedione and Aldehydes
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作者 WANG Li-xin,XU Ming-hua,SHI Yao-zcng and HU Hong-wen (Department of Chemistry,Nanjing University,Nanjing,210008) resent address Chengdu Institute of Organic Chemistry,Acdemia Sinica,Chengdu,610015 Present address:Chengdu lnstutute of Organic Chentistry Acdemia Simca.Chengdu,G10015 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1995年第2期178-184,共7页
Phase transfer catalysis (PTC) has become one of the most extensively used techniques in organic synthesis. The key factor in such processes is the catalyst. There are mainly two kinds of phase transfer catalysts, one... Phase transfer catalysis (PTC) has become one of the most extensively used techniques in organic synthesis. The key factor in such processes is the catalyst. There are mainly two kinds of phase transfer catalysts, one is the so called "crown ethers" including macrocyeles, open chain molecules with long chains, bearing heteroatoms at a proper distance, and can chelate inorganic 展开更多
关键词 phase transfer catalysis 2 5-Piperazincdione Selectivity
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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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Asymmetric Phase-transfer Mediated Epoxidation of α, β-Enones Using Dendritic Catalysts Derived from Cinchona Alkaloids 被引量:1
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作者 XuDongLIU XiaoLiBAI XuePengQIU LianXunGAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第7期975-978,共4页
Chiral phase-transfer catalysts, derived from cinchona alkaloids and Fréchet dendritic wedges up to generation two, have been synthesized. These chiral dendritic molecules have been used as PTCs in the epoxidatio... Chiral phase-transfer catalysts, derived from cinchona alkaloids and Fréchet dendritic wedges up to generation two, have been synthesized. These chiral dendritic molecules have been used as PTCs in the epoxidation of α, β-enones, showing a moderate level of asymmetric induction. 展开更多
关键词 Asymmetric epoxidation phase-transfer catalysis cinchona alkaloids.
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NOVEL BIS—(N—ALKYL—N,N—DIMETHYL AMMONIUM)POLYETHYLENEGLYCOL ETHER SALIS AS PHASE TRANSFER CATALYSTS IN THE CONDENSATION OF 1,4—DIACETYL—2,5—PIPERAZINEDIONE AND ALDEHYDES
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作者 Yao Zeng SHI Li Kin WANG Zheng Ming DU Hong Wen HU Department of Chemistry,Nanjing University Nanjing 210008. Premens addrem Chengdu Institute of O■Chemistry,Acad■Sinics,510015,Chengdu,Sichuan 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1057-1060,共4页
Five novel bis—(N—alkyl—N,N—dimethyl ammoni(?)n)polyethyleneglyool ether salts prepared by our previously reported proced(?)e show high catalytic efficiency in the condensation of 1,4—diacetyl— 2,5—piperazinedi... Five novel bis—(N—alkyl—N,N—dimethyl ammoni(?)n)polyethyleneglyool ether salts prepared by our previously reported proced(?)e show high catalytic efficiency in the condensation of 1,4—diacetyl— 2,5—piperazinedione and aldehydes at both higher and lower temperature even in lower concentration.They al so show catalytic selectivity at lower temperature. 展开更多
关键词 NOVEL BIS ALKYL DIACETYL DIMETHYL AMMONIUM)POLYETHYLENEGLYCOL ETHER SALIS AS phase transfer catalystS IN THE CONDENSATION OF 1 4 N N PIPERAZINEDIONE AND ALDEHYDES AS
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