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Operationally Simple Enantioselective Silane Reduction of Ketones by the [Ir(OMe)(cod)]2/Azolium Catalytic System
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作者 Satoshi Sakaguchi Chika Nagao +1 位作者 Ryo Ichihara Shogo Matsuo 《International Journal of Organic Chemistry》 2024年第1期1-19,共19页
An operationally simple protocol was designed for the enantioselective silane reduction (ESR) of ketones using air- and moisture-stable [Ir(OMe)(cod)]<sub>2</sub> (cod = 1,5-cyclooctadiene) (3) as a metal ... An operationally simple protocol was designed for the enantioselective silane reduction (ESR) of ketones using air- and moisture-stable [Ir(OMe)(cod)]<sub>2</sub> (cod = 1,5-cyclooctadiene) (3) as a metal catalyst precursor. This reaction was driven by chiral hydroxyamide-functionalized azolium salt 2. The catalytic ESR reaction could be performed under benchtop conditions at room temperature. Treatment of 2 with 3 in THF yielded the monodentate IrCl(NHC)(cod) (NHC = N-heterocyclic carbene) complex 4 in 93% yield, herein the anionic methoxy ligand of 3 serves as an internal base that deprotonates the azolium ring of 2. The well-defined Ir complex 4 catalyzed the ESR reaction of propiophenone (6) with (EtO)<sub>2</sub>MeSiH using the pre-mixing reaction procedure. Based on this success, the catalytic ESR reaction was designed and implemented using an in situ-generated NHC/Ir catalyst derived from 2 and 3. Thus, a wide variety of aryl ketones could be reduced to the corresponding optically active alcohols in moderate to excellent stereoselectivities at room temperature without temperature control. Since the high catalytic activity of 3 was observed, we next evaluated several other transition metal catalyst precursors for the catalytic ESR reaction under the influence of 2. This evaluation revealed that Ir(acac)(cod) (acac = acetylacetonate) (28) and [IrCl(cod)]<sub>2</sub> (5) can be successfully used as metal catalyst precursors in the ESR reaction. 展开更多
关键词 Asymmetric Catalysis enantioselective Reduction Hydrosilylation Reaction N-Heterocyclic Carbene IRIDIUM
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Cobalt-Catalyzed Enantioselective Ring-Opening Reactions of Oxa- and Aza-bicyclic Alkenes with Alkenylboronic Acids 被引量:1
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作者 Di Zhu Yongmei Zhao +1 位作者 Qinglei Chong Fanke Meng 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2022年第2期190-194,共5页
Catalytic enantioselective ring-opening of oxa-and aza-bicyclic alkenes with readily available accessible alkenylboronic acids,promoted by a chiral phosphine-Co complex,is reported.Such a process represents the unprec... Catalytic enantioselective ring-opening of oxa-and aza-bicyclic alkenes with readily available accessible alkenylboronic acids,promoted by a chiral phosphine-Co complex,is reported.Such a process represents the unprecedented Co-catalyzed introduction of various alkenyl groups onto the oxa-and aza-bicyclic alkenes,affording a wide range of multisubstituted functionalized cyclohexenes in up to 98%yield and 99.5:0.5 er. 展开更多
关键词 COBALT ring-opening enantioselective catalysis Bicyclic alkene Alkenylboron
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Enantioselective analytical methods in chiral drug metabolism
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作者 洪燕君 高凌波 曾苏 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第3期177-182,共6页
The chiral nature of biological systems enables their stereoselective interaction with chiral compounds. It has been well documented that the enantiomers ofa chiral drug may show differences in drug disposition especi... The chiral nature of biological systems enables their stereoselective interaction with chiral compounds. It has been well documented that the enantiomers ofa chiral drug may show differences in drug disposition especially in metabolic behavior. As a result, it is of vital importance to separate the enantiomers of a chiral drug in metabolic studies. This paper discusses enantioselective methods (include high-performance liquid chromatography, gas chromatography, capillary electrophoresis and high-performance liquid chromatography-mass spectrometry) that applied in chiral drug metabolism, using most recent examples where possible. 展开更多
关键词 enantioselective analytical methods Chiral drug Drug metabolism
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Enantioselective separation and zebrafish embryo toxicity of insecticide beta-cypermethrin 被引量:8
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作者 Chao Xu,Wenqing Tu,Chun Lou,Yingying Hong,Meirong Zhao Research Center of Environmental Science,College of Biological and Environmental Engineering,Zhejiang University of Technology,Hangzhou 310032,China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期738-743,共6页
Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) ... Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval assays.The enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism (CD) at 236 nm.Better separation could be achieved at lower temperature (e.g.,20°C) and with lower levels of polar modifiers.Pure enantiomers were obtained on Chiralcel OD.The CD spectra of enantiomers were recorded.By comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was determined.The individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked body.The 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration (e.g.,0.3 mg/L).The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects. 展开更多
关键词 BETA-CYPERMETHRIN enantioselectIVITY zebrafish embryo chiral separation
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Lipase immobilized on HOOC-MCF:A highly enantioselective catalyst for transesterification resolution of (R,S)-1-phenylethanol 被引量:4
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作者 Ping Xue Xiang Hui Yan Zheng Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期929-932,共4页
Pseudomonas cepacia lipase (PSL) immobilized on the carboxyl-functionalized meso-cellular foams (HOOC-MCF) was used for the transesterification resolution of (R,S)-l-phenylethanol in organic solvent. The results... Pseudomonas cepacia lipase (PSL) immobilized on the carboxyl-functionalized meso-cellular foams (HOOC-MCF) was used for the transesterification resolution of (R,S)-l-phenylethanol in organic solvent. The results showed that the ee value of (S)-1- phenylethanol and (R)-1-phenylethyl acetate reached 99% with 50% conversion of 1-phenylethanol using toluene as solvent. Furthermore, it was found that PSL/HOOC-MCF exhibited high enantioselectivity in organic solvent with log P ≤ 2 such as toluene and hexane. 展开更多
关键词 Immobilized lipase enantioselectIVITY Chiral resolution 1-Phenylethanol
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Baker's yeast mediated reduction of substituted acenaphthenequinones: Regio-and enantioselective preparation of mono-hydroxyacenaphthenones 被引量:2
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作者 Xing Yong Wang, Jing Nan Cui, Wei Min Ren, Feng Li, Chun Liang Lu, Xu Hong Qian State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012, China School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou 221008, China Shanghai Key Laboratory of Chemical Biology, East China University of Science and Technology, Shanghai 200237, China 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期681-684,共4页
Baker's yeast mediated reduction of acenaphthenequinone within 4-10 h afforded mono-hydroxyacenaphthenone mainly with low enantioselectivity, the substrate and mono-hydroxyacenaphthenone product almost converted t... Baker's yeast mediated reduction of acenaphthenequinone within 4-10 h afforded mono-hydroxyacenaphthenone mainly with low enantioselectivity, the substrate and mono-hydroxyacenaphthenone product almost converted to dihydroxyacenaphthene after 48 h. By control of the reaction time and in the presence of DMF as co-solvent, the reduction of 6-substituted acenaphthenequinones under vigorous agitation afforded the corresponding 2-hydroxyacenaphthenones in 24-84% yields with 10-93% ee. 展开更多
关键词 Baker's yeast Reduction Regio- and enantioselectivity Chiral hydroxyacenaphthenone
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Comparison of reversed-phase enantioselective HPLC methods for determining the enantiomeric purity of (S)-omeprazole in the presence of its related substances 被引量:2
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作者 Bruno Gallinella Rosella Ferretti +3 位作者 Leo Zanitti Isabella Sestili Antonina Mosca Roberto Cirilli 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第2期132-136,共5页
A simple analytical high-performance liquid chromatography (HPLC) method was applied for the en- antiomeric excess determination of esomeprazole ((S)-OME), the enantiopure active ingredient con- tained in drug p... A simple analytical high-performance liquid chromatography (HPLC) method was applied for the en- antiomeric excess determination of esomeprazole ((S)-OME), the enantiopure active ingredient con- tained in drug products, in the presence of its potential organic impurities A-E. The enantioselective separation was accomplished on the immobilized-type Chiralpak ID-3 chiral stationary phase (CSP) under reversed-phase conditions. The results were evaluated and compared with those obtained by the official enantioselective method of European Pharmacopoeia used as the reference for checking the enantiomeric excess of (S)-OME. It has been established that the use of the Chiralpak ID-3 CSP allows the determination of the enantiomeric purity of (S)-OME without any interference coming from its chiral and achiral related substances. The analytical procedure of the drug regulatory agencies based on the AGP CSP suffered instead from poor specificity due to overlap of the peaks pertinent to the achiral impurity A and the chiral impurity (R)-OME (impurity F). 展开更多
关键词 Chiralpak ID-3 ENANTIOMERS enantioselective HPLC Impurities(S)-Omeprazole
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Resolution of 2-Octanol via Lipase-catalyzed Enantioselective Acetylation in Organic Solvents 被引量:1
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作者 WANGZhi LIZheng-qiang +4 位作者 YuDa-hai WENGLiang LIUMing ZHANGGui-rong CAOShu-gui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期575-578,共4页
The lipases from different sources were screened for their ability to catalyze the resolution of 2-octanol in organic solvents with vinyl acetate as the acylating reagent. The medium effect has been studied on the irr... The lipases from different sources were screened for their ability to catalyze the resolution of 2-octanol in organic solvents with vinyl acetate as the acylating reagent. The medium effect has been studied on the irreversible transesterification with varying water activity(a_w). The influence of vinyl acetate concentration on it has also been investigated. Under the optimal conditions, the enantiomeric ratio(E value) of pseudomonas fluorescence lipase(PFL) exceeded 200 with an enantiomeric excess(e.e.) of S-2-octanol above 99% at a 51% degree of conversion. 展开更多
关键词 Lipase RESOLUTION Activity enantioselectIVITY 2-OCTANOL
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Ultrasound-promoted Lipase-catalyzed Enantioselective Transesterification of (R,S)-Glycidol 被引量:1
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作者 AN Bai-yi XIE Xiao-na +5 位作者 XUN Er-na WANG Jia-xin WANG Ren SUN Ruo-xi WANG Lei WANG Zhi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第5期845-849,共5页
Enantioselective transesterification of glycidol with vinyl butyrate as an acyl donor was investigated in the presence of Bacillus subtilis lipase(BSL2) as catalyst. Comparison studies demonstrate the advantage of u... Enantioselective transesterification of glycidol with vinyl butyrate as an acyl donor was investigated in the presence of Bacillus subtilis lipase(BSL2) as catalyst. Comparison studies demonstrate the advantage of ultrasound over the conventional shaking for the enzymatic reaction in non-aqueous media. The effects of reaction conditions(ultrasound power, temperature, water activity and pH) on the activity and enantioselectivity were also investigated. Under the optimum conditions, the synthetic activity of BSL2 was 2.95 μmol?min?1?mg?1 and the enantioselectivity(E value) was 52.2. Compared with conventional shaking, ultrasound made the synthetic activity and the enantioselectivity increase 9.5-fold and 1.4-fold, respectively. Furthermore, the repeated use of BSL2 for five cycles resulted in no obvious loss of enzyme activity, suggesting that the enzyme is stable under low power ultrasound conditions. 展开更多
关键词 Activity enantioselectIVITY GLYCIDOL Lipase Resolution ULTRASOUND
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First Enantioselective Synthesis of Daphneticin 被引量:1
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作者 Xin Feng REN Kun PENG +3 位作者 Xiao Chuan CHEN Xin Gang XIE Ya Mu XIA Xin Fu PAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第6期551-554,共4页
An enantioselective total synthesis of chiral daphneticin is reported firstly.
关键词 SYNTHESIS enantioselective coumarinolignoids daphneticin.
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Novel chiral thioureas for highly enantioselective Michael reactions of malonates to nitroalkenes 被引量:1
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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 malo... 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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Enantioselective reduction of acetophenone analogues using carrot and celeriac enzymes system 被引量:1
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作者 Liu, Xiang Pan, Zheng Guang +1 位作者 Xu, Jian He Li, He Xing 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期305-308,共4页
The enantioselective reduction of acetophenone analogues catalyzed by carrot and celeriac was performed in moderate conversions and excellent enantiomeric excesses.The steric factors and electronic effects of the subs... The enantioselective reduction of acetophenone analogues catalyzed by carrot and celeriac was performed in moderate conversions and excellent enantiomeric excesses.The steric factors and electronic effects of the substituents at the aromatic ring were found to significantly affect the efficiency of the enantioselective reduction of acetophenone analogues,while they had a little effect on the enantioselectivity of acetophenone analogues reduction.It was also found that the conversions of acetophenone analogu... 展开更多
关键词 enantioselective reduction Acetophenone analogues Plant cells BIOCATALYSIS
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Enantioselective hydrogenation of acetophenone by(1S,2S)-DPEN-Ru(Ⅱ)Cl_2(PPh_3)_2 encapsulated in Al-MCM-41 被引量:1
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作者 Jian Hong Liu Dong Liang +2 位作者 Bin Bin Fan Rui Feng Li Hua Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期802-806,共5页
A chiral ruthenium complex[(1S,2S)-DPEN]-RuCl_2(PPh_3)_2(DPEN = 1,2-diphenylethylenediamine,PPh_3 = triphenylphosphine) was encapsulated in the channel of Al-MCM-41 by electrostatic adsorption and 1,1-dichlorosi... A chiral ruthenium complex[(1S,2S)-DPEN]-RuCl_2(PPh_3)_2(DPEN = 1,2-diphenylethylenediamine,PPh_3 = triphenylphosphine) was encapsulated in the channel of Al-MCM-41 by electrostatic adsorption and 1,1-dichlorosilacyclobutane modification.The prepared heterogeneous catalyst showed the same catalytic activity and enantioselectivity as the corresponding homogeneous catalyst in the asymmetric hydrogenation of acetophenone,and could be reused at least seven times without significant loss of catalytic activity and enantioselectivity. 展开更多
关键词 ENCAPSULATION AL-MCM-41 Heterogeneous enantioselective hydrogenation ACETOPHENONE S S-DPEN-Ru-Al-MCM-Si
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MODIFICATION OF TRANSITION METAL CATIONS TO POLYMER-STABILIZED PLATINUM COLLOIDAL CLUSTERS IN ENANTIOSELECTIVE HYDROGENATION OF METHYL PYRUVATE 被引量:1
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作者 刘汉范 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第4期393-399,共7页
Modification of transition metal cations to polymer-stabilized Pt colloidal clusters modified with cinchonidine was studied in enantioselective hydrogenation of methyl pyruvate.Compared to the enantiomeric excess(e.e.... Modification of transition metal cations to polymer-stabilized Pt colloidal clusters modified with cinchonidine was studied in enantioselective hydrogenation of methyl pyruvate.Compared to the enantiomeric excess(e.e.)value(71.4%) obtained without the presence of metal cations,obvious e.e.enhancement(up to 82.5%)was resulted from the addition of Zn^(2+) but with a certain decrease in activity.The reaction parameters in the presence of Zn^(2+) were also studied.It was found that the Pt colloidal catalysts in the presence of metal cations performed very differently from that in the absence of metal cations. 展开更多
关键词 Methyl pyruvate Colloidal platinum clusters Transition metal cations enantioselective hydrogenation
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RING-OPENING POLYMERIZATION OF TRIMETHYLENE CARBONATE CATALYZED BY NOVEL SINGLE COMPONENT RARE EARTH CALIXARENE COMPLEXES 被引量:3
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作者 沈之荃 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第4期407-410,共4页
In this paper,ring-opening polymerization of trimethylene carbonate(TMC)with rare earth(Nd,Y,La)ρ-tert- butylcalix[n]arene(n=4,6,and 8)complexes as catalysts has been studied.Poly(trimethylene carbonate)(PTMC)with M_... In this paper,ring-opening polymerization of trimethylene carbonate(TMC)with rare earth(Nd,Y,La)ρ-tert- butylcalix[n]arene(n=4,6,and 8)complexes as catalysts has been studied.Poly(trimethylene carbonate)(PTMC)with M_v of 21,400 was produced by bulk polymerization under the conditions as follows:[TMC]_0/[Nd](molar ratio)=1000,80℃, 8 h.Mechanism study reveals that the polymerization proceeds via a coordination mechanism. 展开更多
关键词 ring-opening polymerization Trimethylene carbonate CALIXARENE Rare earth complex
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A Simple and Highly Efficient Enantioselective Synthesis of (<i>S</i>)-Rivastigmine 被引量:3
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作者 Veera R. Arava Laxminarasimhulu Gorentla Pramod K. Dubey 《International Journal of Organic Chemistry》 2011年第2期26-32,共7页
A highly efficient and convenient procedure for the enantioselective synthesis of (S)-Rivastigmine, a cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer’s type and dementia due to Parki... A highly efficient and convenient procedure for the enantioselective synthesis of (S)-Rivastigmine, a cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer’s type and dementia due to Parkinson’s disease, is accomplished by the treatment of versatile, readily accessible (S)-(-)-2-methyl-2-propanesulfinamide with 3-hydroxyacetophenone. This protocol provides high yield and excellent enantiomeric excess in short step synthesis. 展开更多
关键词 CHOLINERGIC Agent enantioselective Highly Efficient (S)-(-)-2-Methyl-2-Propane Sulfina-mide (S)-Rivastigmine
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Ring-opening Polymerization ofε-Caprolactone Using Lanthanide Tris(4-tert-butylphenolate)s as a Single-component Initiator 被引量:4
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作者 Cui Ping YU, Li Fang ZHANG, Zhi Quan SHEN Institute of Polymer Science, Zhejiang University, Hangzhou 310027 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期1021-1023,共3页
The ring-opening polymerization of e-caprolactone (CL) initiated by novel single lanthanide tris(4-tert-butylphenolate)s [Ln(OTBP)3] is reported. Single-component La(OTBP)3 can effectively prepare polycaprolactone (PC... The ring-opening polymerization of e-caprolactone (CL) initiated by novel single lanthanide tris(4-tert-butylphenolate)s [Ln(OTBP)3] is reported. Single-component La(OTBP)3 can effectively prepare polycaprolactone (PCL) with over 90% yield and viscosity average molecular weight about 60 x 10 under quite mild conditions: molar ratio of CL to initiator is 1000, 60 C, 2 h in toluene. Mechanism study indicates that the monomer inserts into the growing chain via the break of acyl-oxygen bond of CL. 展开更多
关键词 Lanthanide tris(4-tert-butylphenolate)s e-caprolactone ring-opening polymerization.
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Enantioselective assay of S(+)- and R(-)-propafenone in human urine by using RP-HPLC with pre-column chiral derivatization 被引量:3
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作者 吴永江 马明铭 曾苏 《Journal of Zhejiang University Science》 CSCD 2004年第2期226-229,共4页
The enantioselective assay for S(+)- and R(-)-propafenone (PPF) in human urine that developed in this work involves extraction of propafenone from human urine and using S(+)-propafenone as internal standard, chiral de... The enantioselective assay for S(+)- and R(-)-propafenone (PPF) in human urine that developed in this work involves extraction of propafenone from human urine and using S(+)-propafenone as internal standard, chiral derivatization with 2,3,4,6-tetra-O-b-D-glucopranosyl isothiocyanate, and quantitation by an RP-HPLC system with UV detection (l=220 nm). A baseline separation of propafenone enantiomers was achieved on a 5-mm reverse phase ODS column, with a mixture of methanol:water:glacial acetic acid (25:12:0.02,v/v) as mobile phase. There was good linear relationship from 24.9 ng/ml to 1875.0 ng/ml for both of enantiomers. The regression equations of the standard curves based on CS-PPF (or CR-PPF ) versus ratio of AS-PPF/AS (or AR-PPF/AS ) were y=0.0032x-0.081, (r=0.999) for S-PPF and y=0.0033x+0.0039, (r=0.998) for R-PPF, respectively. The method抯 limit of detection was 12.5 ng/ml for both enantiomers, and the method抯 limit of quantitation was 28.20.52 ng/ml for S-PPF, 30.40.53 ng/ml for R-PPF (RSD<8%, n=5). The analytical method yielded average recovery of 98.9% and 100.4% for S-PPF and R-PPF, respectively. The relative standard deviation was no more than 6.11% and 6.22% for S-PPF and R-PPF, respectively. The method enabled study of metabolism of S(+)- and R(-)-propafenone in human urine. The results from 7 volunteers administered 150 mg racemic propafenone indicated that propafenone enantiomers undergo stereoselective metabolism and that in the human body, S(+)-propafenone is metabolized more extensively than R(-)- propafenone. 展开更多
关键词 enantioselective assay PROPAFENONE Human urine Chiral derivatization High-performance liquid chroma-tography
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RING-OPENING POLYMERIZATION OFε-CAPROLACTONE USING LANTHANIDE TRIS(N-PHENYL-3,5-DI-T-BUTYLSALICYLALDIMINATO)S AS SINGLE COMPONENT CATALYST 被引量:2
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作者 沈之荃 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第5期541-544,共4页
Ring-opening polymerization of ε-caprolactone has been carried out by using rare earth Schiff base complexes: lanthanide tris(N-phenyl-3,5-di-t-butylsalicylaldiminato)s [Ln(OPBS)3] as single component catalyst f... Ring-opening polymerization of ε-caprolactone has been carried out by using rare earth Schiff base complexes: lanthanide tris(N-phenyl-3,5-di-t-butylsalicylaldiminato)s [Ln(OPBS)3] as single component catalyst for the first time. The influences of different rare earth elements, monomer and catalyst concentration as well as reaction time on the polymerization were investigated. Mechanism studies showed that monomer inserts into the active site with the acyl-oxygen bond scission rather than the break of alkyl-oxygen bond. 展开更多
关键词 ring-opening polymerization Ε-CAPROLACTONE Lanthanide Schiff base complex.
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SYNTHESIS, CHARACTERIZATION AND RING-OPENING POLYMERIZATION OF CYCLIC (ARYLENE PHOSPHONATE) OLIGOMERS 被引量:2
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作者 陈天禄 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第1期83-89,共7页
A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yie... A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yield of cyclic (arylene phosphonate) oligomers is over 85% by using hexadecyltrimethylammoniun bromide as phase transfer catalyst (PTC) at 0 'C . The structures of the cyclic oligomers were confirmed by a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and IR analysis. These cyclic oligomers undergo facile ring-opening polymerization in the melt by using potassium 4,4'-biphenoxide as the initiator to give linear polyphosphonate. Free-radical ring-opening polymerization of cyclic(arylene phosphonate) oligomers containing sulfur linkages was also performed in the melt using 2,2'-dithiobis(benzothiazole) (DTB) as the initiator at 270 °C and the resulting polymer had a Mw, of 8 × 103 with a molecular weight distribution of 4. Ring-opening copolymerization of these cyclic oligomers with cyclic carbonate oligomers was also achieved. The average molecular weight of the resulting copolymer is higher than the corresponding homopolymer and the thermal stability of the copolymer is better than the corresponding homopolymer. 展开更多
关键词 Cyclic(arylene phosphonate) oligomer ring-opening polymerization COPOLYMER
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