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Upper-rim-modified thioether thiacalix[4]arene used for liquid-liquid extraction of Au(Ⅲ)and Pd(Ⅱ)in hydrochloric acid medium
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作者 Sheng Wan Rong Xie +1 位作者 Jianhong Fan Kewen Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期110-118,共9页
Gold(Au)and palladium(Pd)play an increasing role in the production and human life;Therefore,it is of great significance to study their recovery.A 5,11,17,23-tetra-ethylthio-25,26,27,28-tetra-hydroxyl thiacalix[4]arene... Gold(Au)and palladium(Pd)play an increasing role in the production and human life;Therefore,it is of great significance to study their recovery.A 5,11,17,23-tetra-ethylthio-25,26,27,28-tetra-hydroxyl thiacalix[4]arene(TCAET)was synthesized specifically for the capture of Au(Ⅲ)and Pd(Ⅱ)from HCl medium by liquid-liquid extraction.In a 0.1 mol·L^(-1)HCl medium,the transfer of Au(Ⅲ)and Pd(Ⅱ)from the aqueous phase to the organic phase was highly efficient,with a transfer ratio of 100%for Au(Ⅲ)and 98%for Pd(Ⅱ).Furthermore,the extraction equilibrium time for Au(Ⅲ)was just 5 min.Job's method data demonstrated that TCAET formed complexes with Au(Ⅲ)and Pd(Ⅱ)in a ratio of 2:3 and 1:1,respectively,during the extraction process.TCAET showed high selectivity toward Pd(Ⅱ)and Au(Ⅲ)over other competing metal ions.Moreover,both Au(Ⅲ)and Pd(Ⅱ)could be successfully stripped from the loaded organic phases with a 1.0 mol·L^(-1)thiourea in 0.5 mol·L^(-1)HCl and 0.5 mol·L^(-1)thiourea in 0.5 mol·L^(-1)HCl,respectively.Results obtained from five consecutive extraction-stripping cycles showed good reusability of TCAET toward Au(Ⅲ)and Pd(Ⅱ)recovery.The conclusion can provide a certain reference for thiacalixarene in the recovery of precious metal species. 展开更多
关键词 arene Upper-rim modification Liquid-liquid extraction Precious metal thioether
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N-heterocyclic carbene as a promising metal-free electrocatalyst with high efficiency for nitrogen reduction to ammonia 被引量:5
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作者 Hongyan Li Le Yang +3 位作者 Zhongxu Wang Peng Jin Jingxiang Zhao Zhongfang Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第7期78-86,I0003,共10页
Electrocatalytic nitrogen reduction reaction(NRR)at ambient conditions holds great promise for sustainably synthesizing ammonia(NH3),while developing highly-efficient,long-term stable,and inexpensive catalysts to acti... Electrocatalytic nitrogen reduction reaction(NRR)at ambient conditions holds great promise for sustainably synthesizing ammonia(NH3),while developing highly-efficient,long-term stable,and inexpensive catalysts to activate the inert N≡N bond is a key scientific issue.In this work,on the basis of the concept"N-heterocyclic carbenes(NHCs)",we propose a carbon decorated graphitic-carbon nitride(C/g-C3N4)as novel metal-free NRR electrocatalyst by means of density functional theory(DFT)computations.Our results reveal that the introduced C atom in g-C3N4 surface can be regarded as NHCs and catalytic sites for activating N≡N bond,and are stabilized by the g-C3N4 substrate due to sterically disfavored dimerization.Especially,this NHCs-based heterogeneous catalysis can efficiently reduce the activated N2 molecule to NH3 with a low overpotential of 0.05 V via an enzymatic mechanism.Our work is the first report of NHCs-based electrocatalyst for N2 fixation,thus opening an alternative avenue for advancing sustainable NH3 production. 展开更多
关键词 Nitrogen reduction reaction n-heterocyclic carbenes OVERPOTENTIAL Density functional theory
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Preparation and Properties of Vegetable-Oil-Based Thioether Polyol and Ethyl Cellulose Supramolecular Composite Films
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作者 Ruyu Yan Jian Fang +7 位作者 Xiaohua Yang Na Yao Mei Li Yuan Nie Tianxiang Deng Haiyang Ding Lina Xu Shouhai Li 《Journal of Renewable Materials》 SCIE EI 2023年第4期1937-1950,共14页
Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes i... Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes it too brittle to be used widely.The hydroxyl group on EC can form a supramolecular system in the form of a non-covalent bond with an effective plasticizer.In this study,an important vegetable-oil-based derivative named dimer fatty acid was used to prepare a novel special plasticizer for EC.Dimer-fatty-acid-based thioether polyol(DATP)was synthesized and used to modify ethyl cellulose films.The supramolecular composite films of DATP and ethyl cellulose were designed using the newly-formed van der Waals force.The thermal stability,morphology,hydrophilicity,and mechanical properties of the composite films were all tested.Pure EC is fragile,and the addition of DATP makes the ethyl cellulose films more flexible.The elongation at the break of EC supramolecular films increased and the tensile strength decreased with the increasing DATP content.The elongation at the break of EC/DATP(60/40)and EC/DATP(50/50)was up to 40.3%and 43.4%,respectively.Noticeably,the thermal initial degradation temperature of the film with 10%DATP is higher than that of pure EC,which may be attributed to the formation of a better supramolecular system in this composite film.The application of bio-based material(EC)is environmentally friendly,and the novel DATP can be used as a special and effective plasticizer to prepare flexible EC films,making it more widely used in energy,chemical industry,materials,agriculture,medicine,and other fields. 展开更多
关键词 Ethyl cellulose dimeric fatty acid based thioether polyol supramolecular system composite films
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Effect of Different Loadings on the Performance of Ni2P/Al2O3 Catalysts for Low-Temperature Thioethering and Selective Hydrogenation of Diolefins in Liquefied Petroleum Gas
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作者 Xiao Han Sun Jinru +6 位作者 Song Guoliang Xie Xianna Ke Ming Tong Yanbing Zhao Zhiping Wang Zijian Li Jiahan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第1期79-90,共12页
In this study,different loadings of x%Ni_(2)P/γ-Al_(2)O_(3)(x=6%,9%,12%,15%,18%)catalysts with aluminum oxide(Al_(2)O_(3))as the carrier,nickel chloride(NiCl2)as the nickel(Ni)source,and ammonium hypophosphite(NH_(4)... In this study,different loadings of x%Ni_(2)P/γ-Al_(2)O_(3)(x=6%,9%,12%,15%,18%)catalysts with aluminum oxide(Al_(2)O_(3))as the carrier,nickel chloride(NiCl2)as the nickel(Ni)source,and ammonium hypophosphite(NH_(4)H_(2)PO_(2))as the phosphorus(P)source were prepared by the equal volume impregnation method to investigate the effects of different loadings on the performance of the selective hydrogenation of diolefins and thiol etherification in LPG.The physicochemical properties of the catalysts were characterized by XRD,BET,SEM,TEM,H_(2)-TPR,and XPS,and the catalytic activity of the catalysts was evaluated in a fixed-bed microreactor.The results showed that a change in the loading affected the catalyst crystalline phase structure and size,specific surface area,P coverage,active phase dispersion,and catalytic activity.At 6%,9%,and 12%loadings the catalysts had an Ni phase but there was no obvious Ni_(2)P phase in the nickel phosphide;at 15%loading a single Ni_(2)P phase was obtained,and at 18%loading both Ni_(2)P and Ni1_(2)P_(5) phases appeared.There was a P enrichment on the catalyst surface,and the higher the loading the more P species were enriched on the surface,but some of the P was lost during the catalyst reduction process due to the production of phosphine(PH3)gas.The 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the largest Ni/Al ratio and the best dispersion.The Ni_(2)P active phase size was small at about 4.25 nm and Ni_(2)P was uniformly dispersed on the catalyst surface without agglomeration.The 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the best catalytic activity at a pressure of 2.0 MPa,a liquid hourly space velocity(LHSV)of 3.0 h-1,and a hydrogen to hydrocarbon ratio of 12.The 1,3-butadiene conversion was 97.45%and the methanethiol removal was 100%at a temperature of 140℃. 展开更多
关键词 Ni_(2)P DISPERSION low-temperature thioethering selective hydrogenation of diolefins
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N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations 被引量:2
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作者 Yi Zhang Hui Cai +1 位作者 Xiuhai Gan Zhichao Jin 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第2期482-511,共30页
N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically reviewed.The content is organized according to the activation modes i... N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically reviewed.The content is organized according to the activation modes involved in these transformations.Future advances within this highly active research field are discussed from our perspectives on the topic. 展开更多
关键词 n-heterocyclic carbene kinetic resolution dynamic kinetic resolution DESYMMETRIZATION ORGANOCATALYSIS
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基于银型苯基磺酸键合硅胶分离及高分辨质谱分析石油中不同形态含硫化合物
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作者 李硕凡 刘雨轩 +5 位作者 吴建勋 王婧 朱悦 张未来 张亚和 史权 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第3期763-773,共11页
建立一种基于银型苯基磺酸键合硅胶(Ag+-SCX)分离石油中不同形态含硫化合物的方法,分离得到的含硫化合物组分进行甲基化反应和高分辨质谱(HRMS)分析,得到不同形态含硫化合物分子组成。通过模型化合物证明该分离方法的可行性,硫醚类、噻... 建立一种基于银型苯基磺酸键合硅胶(Ag+-SCX)分离石油中不同形态含硫化合物的方法,分离得到的含硫化合物组分进行甲基化反应和高分辨质谱(HRMS)分析,得到不同形态含硫化合物分子组成。通过模型化合物证明该分离方法的可行性,硫醚类、噻吩类含硫化合物被有效分离。该方法对石油馏分、原油和二次加工油均有良好的适用性,并将其应用于一套原油及其馏分中含硫化合物的分离及分析,详细表征了不同形态含硫化合物在原油和各馏分段的分子组成特点和分布规律。 展开更多
关键词 分离方法 高分辨质谱 硫醚 噻吩 分子组成 原油
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Chemoselective Transfer Hydrogenation of Nitroarenes with Ammonia Borane Catalyzed by Copper N-Heterocyclic Carbene Complexes
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作者 Hui Zhou Hongmei Jiao +5 位作者 Xing Lu Yuanyuan Gao Zhiqiang Ren Haojie Ma Yuqi Zhang Bo Han 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第15期1721-1726,共6页
Herein,we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading(1 mo%)of copper N-heterocyclic carbene complexes as the catalyst and ammonia borane as the sou... Herein,we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading(1 mo%)of copper N-heterocyclic carbene complexes as the catalyst and ammonia borane as the source of hydrogen.A wide range of nitroarenes,featuring diverse functional groups,were selectively transformed into their corresponding primary aromatic amines with high yields.This process can be readily scaled up and exhibits compatibility with various sensitive functional groups,including halogen,trifluoromethyl,aminomethyl,alkenyl,cyano,ester,amide,and hydroxyl.Notably,this catalytic methodology finds application in the synthesis of essential drug compounds.Mechanistic investigations suggest that the in-situ-generated Cu-H species may serve as active intermediates,with reduction pathways involving species such as azobenzene,1,2-diphenylhydrazine,nitrosobenzene,and N-phenylhydroxylamine. 展开更多
关键词 Homogeneous catalysis HYDROGENATION n-heterocyclic carbene complexes NITROARENES Ammonia borane
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Recent advances in the synthesis and application of N-heterocyclic carbene-based molecular cages
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作者 Qiongjie Chai Lixin Duan +2 位作者 Yanzhe Ma Tianheng Hou Tao Tu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第5期1510-1523,共14页
N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the des... N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the design, synthesis, and application of these corresponding cages have garnered substantial scholarly interest. In recent years, we have witnessed the successful fabrication of diverse NHC-based cages through a range of synthetic methodologies, which hold significant potential for applications in molecular recognition and catalysis. In this review, we delve into the foundational synthetic strategies that underlie the creation of NHC-based cages, employing approaches encompassing metal–NHC chelation, coordination assembly,and covalent bonding. Additionally, we compile the diverse applications of these cages within catalytic processes and molecular recognition. Lastly, we shed light on the current limitations of synthesis and outline future trends in the development of NHCbased cages. 展开更多
关键词 n-heterocyclic carbene molecular cages supramolecular chemistry synthetic strategies APPLICATIONS
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Vanadium(V) Complexes Containing Unsymmetrical N-Heterocyclic Carbene Ligands: Highly Efficient Synthesis and Catalytic Behavior towards Ethylene/Propylene Copolymerization
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作者 Yi-Cong Wang Hui Zhat +3 位作者 Pei-Yi Cheng Shu Zhang Xiang-Wei Liu Yi-Xian Wu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第1期32-41,I0006,共11页
The highly efficient method has been developed for the synthesis of NHC·VOCl_(3) containing symmetrical or unsymmetrical Nheterocyclic carbene(NHC) ligands by the transmetallation reaction of NHC·AgCl with V... The highly efficient method has been developed for the synthesis of NHC·VOCl_(3) containing symmetrical or unsymmetrical Nheterocyclic carbene(NHC) ligands by the transmetallation reaction of NHC·AgCl with VOCl_(3).The total isolated yield of VOCl_(3)[1,3-(2,4,6-Me_(3)C_(6)H_(2))_(2)(NCH=)_(2)C:](V4') reached 86% by transmetallation reaction,which is much higher than that(48%) by direct coordination method.This methodology has also been used to synthesize the novel vanadium complexes containing unsymmetrical NHC ligands of VOCl_(3)[PhCH_(2)NCH=CHNR)C:](V5',R=2,4,6-Me_(3)C_(6)H_(2);V6',R=2,4-Me_(2)-6-Ph-C_(6)H_(2);V7',R=2,6-^(i)Pr_(2)-C_(6)H_(3)) with high yield,which could not be obtained by direct coordination method.The catalytic activity and copolymerization ability would be improved by introducing unsymmetrical NHC ligands due to their less steric bulky effect.The vanadium complex V5' containing unsymmetrical NHC ligand exhibits higher catalytic activity(3.7×10^(5)g_(copolymer)·mol^(-1) of V·h^(-1)) than that of V4' containing symmetrical NHC ligand.Moreover,the higher propylene incorporation ratio(45.6 mol%) in the copolymers of ethylene with propylene could be obtained by using V5' than that(39.9%) by using V4'.The results would provide a highly efficient strategy for the synthesis of early transition metal complexes containing versitile NHC ligands,affording the catalyst with both high catalytic activity and copolymerization ability for the synthesis of high performance polyolefin elastomers. 展开更多
关键词 Vanadium complex n-heterocyclic carbene ligand Transmetallation reaction Copolymerization of ethylene with propylene
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Enantioselective Alkylation of Aldehydes with Organoborons Enabled by Nickel/N-Heterocyclic Carbene Catalysis
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作者 Song-Yang Liu Zi-Chao Wang Shi-Liang Shi 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第18期2161-2165,共5页
Transition-metal-catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary alcohols.However,efficient methods using organoborons as coupling reagents are ... Transition-metal-catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary alcohols.However,efficient methods using organoborons as coupling reagents are rare.Herein,we report a highly enantioselective nickel-catalyzed alkylation reaction of aldehydes,using readily available alkylborons as nucleophiles.A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high yields.The key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2-symmetric chiral NHC ligand.This protocol features excellent enantiocontrol,mild conditions,and good functional group compatibility. 展开更多
关键词 Enantioselective alkylation Nickel catalysis n-heterocyclic carbene Organoborons Chiral alcohols Asymmetric catalysis C-C coupling Synthetic methods
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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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硫醚氧化为亚砜和砜的研究进展
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作者 李素 余志群 《浙江化工》 CAS 2024年第3期12-17,共6页
亚砜和砜是两类重要的化合物,在化学和生物领域有广泛的应用。虽然有很多方法合成亚砜和砜,但通过控制硫醚的化学选择性氧化是合成亚砜和砜的常用途径之一;常见氧化剂如空气/氧气、双氧水、单过硫酸氢钾复合盐(Oxone)、高碘酸钠等均可... 亚砜和砜是两类重要的化合物,在化学和生物领域有广泛的应用。虽然有很多方法合成亚砜和砜,但通过控制硫醚的化学选择性氧化是合成亚砜和砜的常用途径之一;常见氧化剂如空气/氧气、双氧水、单过硫酸氢钾复合盐(Oxone)、高碘酸钠等均可以实现硫醚的选择性氧化。本文依据氧化剂的种类对氧化反应进行分类,综述了近年来硫醚氧化制备亚砜和砜的研究进展。 展开更多
关键词 硫醚 亚砜 氧化反应 氧化剂
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混装分子筛脱除油田伴生气中硫醚的研究与应用
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作者 李春秀 刘连鹏 +4 位作者 刘元直 陈平文 刘波 徐东梅 周政 《山东化工》 CAS 2024年第13期76-79,共4页
针对含有饱和水和微量羰基硫、硫醚等有机硫的油田伴生气,提出4A分子筛和13X改性分子筛混装的脱水脱硫方法。结合现场生产工况,利用工程模拟软件对主要有机硫组分在分子筛上的吸附和再生能量进行了核算,确定了再生气量、再生压力、再生... 针对含有饱和水和微量羰基硫、硫醚等有机硫的油田伴生气,提出4A分子筛和13X改性分子筛混装的脱水脱硫方法。结合现场生产工况,利用工程模拟软件对主要有机硫组分在分子筛上的吸附和再生能量进行了核算,确定了再生气量、再生压力、再生温度等关键参数,实现了脱硫分子筛的吸附再生循环,在保证脱水效果的情况下,达到了脱硫的目的。 展开更多
关键词 混装分子筛 油田伴生气 硫醚 分子模拟
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无金属催化β-取代硫醚的合成研究
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作者 李春生 陈耀杨 叶非华 《肇庆学院学报》 2024年第5期78-83,97,共7页
研究以多种简单易得的烯烃与苯硫酚为原料,以高产率合成2类不同类型的β-氯代硫醚及β-羟基取代硫醚.反应通过选择不同的反应溶剂,实现不同产物的选择性合成.当以无水乙腈为溶剂时,可以中等至高的收率生成得到β-氯代硫醚;而在溶剂二甲... 研究以多种简单易得的烯烃与苯硫酚为原料,以高产率合成2类不同类型的β-氯代硫醚及β-羟基取代硫醚.反应通过选择不同的反应溶剂,实现不同产物的选择性合成.当以无水乙腈为溶剂时,可以中等至高的收率生成得到β-氯代硫醚;而在溶剂二甲基亚砜中,则可选择性地生成β-羟基取代硫醚.该反应有较好的底物适应性,官能团容忍度,并具有操作简便、反应条件温和等优点. 展开更多
关键词 无金属催化 烯烃 双官能团化 β-取代硫醚 结构表征
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Co(Ⅱ)2,2',4,4'-四羟基二苯甲酮-乙二胺席夫碱配合物的合成及其催化硫醚不对称氧化的探究
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作者 唐洁 覃昌铭 《化工设计通讯》 CAS 2024年第8期23-25,共3页
手性席夫碱(Schiff base)配合物催化的硫醚不对称氧化反应是现有最有效的方法之一。利用2,2’,4,4’-四羟基二苯甲酮-乙二胺反应合成席夫碱配体,水热法合成配合物(CoL_(1))。考察了在牛血清白蛋白存在下CoL_(1)催化硫醚不对称氧化反应... 手性席夫碱(Schiff base)配合物催化的硫醚不对称氧化反应是现有最有效的方法之一。利用2,2’,4,4’-四羟基二苯甲酮-乙二胺反应合成席夫碱配体,水热法合成配合物(CoL_(1))。考察了在牛血清白蛋白存在下CoL_(1)催化硫醚不对称氧化反应的催化活性,并考察了缓冲溶液pH、氧化剂浓度、底物浓度、氧化剂种类、反应温度等反应条件对催化活性的影响。通过单因素实验探究实验,得到了CoL_(1)催化苯基甲基硫醚不对称氧化反应的最优反应条件,获得了79.72%的转化率和99.13%的化学选择性,但对映体选择性较低(7.91%)。 展开更多
关键词 硫醚不对称氧化 席夫碱配合物 手性亚砜 牛血清白蛋白
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Synthesis and Adsorption Studies on Magnetic Microbeads of Polythioether-arylamine Resins 被引量:1
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作者 张超灿 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第3期56-59,共4页
By the suspended condensation reaction of poly(choloromethylthiirane)with o-tolidine and o- dianisidine respectively, two newmicrobeads chelating resins were synthesized by usingγ-Fe_2O_3 asmagnetic core. Their adsor... By the suspended condensation reaction of poly(choloromethylthiirane)with o-tolidine and o- dianisidine respectively, two newmicrobeads chelating resins were synthesized by usingγ-Fe_2O_3 asmagnetic core. Their adsorption properties for Hg(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), Pb(Ⅱ), Au(Ⅲ), Pd(Ⅱ), Pt (Ⅳ)and Ag(Ⅰ)were investigated. Themicrobeads posses excellent adsorbability for Hg(Ⅱ) and noble metalions, and predominantly adsorbed Pd(Ⅱ)or Hg(Ⅱ)in the coexistence ofCu(Ⅱ), Zn(Ⅱ)and Mg(Ⅱ). 展开更多
关键词 magnetic chelating resin dianisidine thioether
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Green Synthesis of Aryl Thioethers through Cu-catalysed C-S Coupling of Thiols and Aryl Boronic Acids in Water 被引量:1
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作者 TU Peihua LI Xinhua 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期987-993,共7页
An efficient, practical, highly selective and environmentally benign method is reported for the synthesis of aryl thioethers via the coupling of thiols with aryl boronic acids in the presence of NaOH and a catalytic a... An efficient, practical, highly selective and environmentally benign method is reported for the synthesis of aryl thioethers via the coupling of thiols with aryl boronic acids in the presence of NaOH and a catalytic amount of CuSO4 at 130 ℃ using water as a green solvent. The products were obtained in moderate to excellent yields;more importantly, the use of toxic ligands and solvents was avoided. A broad range of aryl boronic acids and scalable processes make this methodology valuable and versatile for the synthesis of a broad range of aryl sulfides. 展开更多
关键词 green synthesis Cu-catalysed C-S COUPLING ARYL boronic acids WATER solvent ARYL thioether
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Recent advances in heterogeneous catalytic hydrogenation and dehydrogenation of N-heterocycles 被引量:3
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作者 Zhongzhe Wei Fangjun Shao Jianguo Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第7期980-1002,共23页
The selective hydrogenation of quinolines to 1,2,3,4-tetrahydroquinolines(py-THQ) and its derivatives has attracted a considerable amount of attention as they show great versatility in many pharmaceuticals, agrochemic... The selective hydrogenation of quinolines to 1,2,3,4-tetrahydroquinolines(py-THQ) and its derivatives has attracted a considerable amount of attention as they show great versatility in many pharmaceuticals, agrochemicals, and fine chemicals. Over the past few decades, great breakthroughs have been achieved in the controlled synthesis of efficient heterogeneous catalysts used for the selective hydrogenation of functionalized quinoline compounds, which allow one to correlate the structure-property relationships. In this review, we will summarize the recent significant progress achieved in this field covering the synthetic strategies, microstructural and chemical features, catalytic performance, and internal relationships. State-of-the-art noble metal-based single(Pd, Pt, Ru, Rh, Ir and Au) and bi/multi-metallic catalysts(RuCu, AuPd, and PdNi) are first introduced, followed by a summary of earth-abundant metal-based catalysts(Co, Fe, Ni, and Cu). Finally, the dehydrogenation of N-heterocycles is introduced to form a reversible hydrogenation/dehydrogenation system for H2 storage, which can be employed in a liquid organic hydrogen system. Furthermore, the reaction mechanism and future research direction in these areas are also discussed. This review will deepen our understanding of the catalytic transformation of N-heterocycles and provide guidance for researchers on the rational design of catalysts. 展开更多
关键词 n-heterocyclES Selective hydrogenation DEHYDROGENATION Heterogeneous catalysts Structure-activity relationship
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A thioether-functionalized pyrene-based covalent organic framework anchoring ultrafine Au nanoparticles for efficient photocatalytic hydrogen generation 被引量:1
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作者 Zhiming Zhou Chuanbiao Bie +2 位作者 Peize Li Bien Tan Yan Shen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2699-2707,共9页
Covalent organic frameworks(COFs)have lately emerged as a blooming class of potential materials for photocatalytic water splitting because of their high crystallinity,huge surface areas,and structural versatility.Howe... Covalent organic frameworks(COFs)have lately emerged as a blooming class of potential materials for photocatalytic water splitting because of their high crystallinity,huge surface areas,and structural versatility.However,the photocatalytic performance for most pure COFs face some limitations factors,such as the significant recombination of photogenerated carriers and slow charge transfer.Herein,a novel thioether-functionalized pyrene-based COF(S_(4)-COF)was effectively produced and chosen as a support for the immobilization of ultrafine gold nanoparticles(Au NPs).S_(4)-COF photocatalyst with Au as cocatalyst demonstrates remarkable photocatalytic activity with a H_(2) generation rate of 1377μmol g^(−1) h^(−1) under visible light(>420 nm),which is ca.4.5-fold increase comparing to that of pure S_(4)-COF(302μmol g^(−1) h^(−1)).Au NPs anchored on S_(4)-COF possess an ultrafine size distribution ranging from 1.75 to 6.25 nm with an average size centered at 3.8 nm,which benefits from the coordination interaction between thioether groups and Au.Meanwhile,the produced Au@S_(4)-COF can generate a stable photocatalytic H_(2) generation during the four recycles and preserve its crystallinity structure after the stability testing.The Au NPs anchored on the S_(4)-COF photocatalyst can greatly accelerate the separation of photogenerated carriers and increase charge transfer because of the combined function of Au NPs and thioether groups.Such a method can not only prevent the aggregation of Au NPs onto thioether-containing COFs to achieve long-term photostability but also allow uniform dispersion for an ordered structure of photocatalysts.This work provides a rational strategy for designing and preparing COF-based photocatalysts for solar-driven H_(2) production. 展开更多
关键词 Photocatalysis Covalent organic framework thioether functionalization Gold nanoparticle Coordination interaction Photogenerated carrier separation
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Synthesis of core-shell structured polymers with inserted thioether from a multi-functional scaffold
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作者 Pu, Hong Ting Zhou, Qing Wan, De Cheng 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期758-761,共4页
The synthesis of a thioether inserted, core-shell structured polymer from the scaffold of hyperbranched polyglycerol (PG) was described. PG was first allyl functionalized, and in the presence of AlBN, the allyl groups... The synthesis of a thioether inserted, core-shell structured polymer from the scaffold of hyperbranched polyglycerol (PG) was described. PG was first allyl functionalized, and in the presence of AlBN, the allyl groups further underwent radical addition to thiol compounds, thus thiol functional polyethylene oxide monomether (MPEO) were grafted onto PG. Similarly, 2-mercaptoethylammonium chloride was introduced onto PG via thiol addition, and the residual amino groups were further quaternized with decyl bromide, leading to an amphiphilic core-shell structure polymer. (c) 2007 De Cheng Wan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 CORE-SHELL SCAFFOLD thioether radical addition hyperbranched polymer
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