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Extractant(2,3-dimethylbutyl)(2,4,40-trimethylpentyl) phosphinic acid(INET-3) impregnated onto XAD-16 and its extraction and separation performance for heavy rare earths from chloride media 被引量:6
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作者 Junlian Wang Meiying Xie +2 位作者 Juanjuan Ma Huajun Wang Shengming Xu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第12期1239-1247,共9页
(2,3-Dimethylbutyl)(2,4,40-trimethylpentyl)phosphinic acid(INET-3) was impregnated onto dry macroporous resins XAD-16 and pretreated XAD-16 with ethyl alcohol and HCl(Pre-XAD-16) to prepare the solvent impregn... (2,3-Dimethylbutyl)(2,4,40-trimethylpentyl)phosphinic acid(INET-3) was impregnated onto dry macroporous resins XAD-16 and pretreated XAD-16 with ethyl alcohol and HCl(Pre-XAD-16) to prepare the solvent impregnated resins SIRs-INET-3/XAD-16 and SIRs-INET-3/Pre-XAD-16. The molecular weight distribution of the low molecular weight(LMW) polymers washed off by ethyl alcohol during XAD-16 pretreatment was determined by gel permeation chromatography(GPC). The macroporous resins(XAD-16 & Pre-XAD-16), the corresponding solvent impregnated resins(SIRs-INET-3/XAD-16 &SIRs-INET-3/Pre-XAD-16) and the PVA coated SIRs-INET-3/Pre-XAD-16 with boric acid as cross-linking agent were characterized by FT-IR, SEM-EDS and TGA. The effects of XAD-16 pretreatment and PVA coating technology on RE(III) adsorption equilibrium time, INET-3 losses during extraction and adsorption capacity were investigated. The adsorption kinetics, selectivity and stripping behaviors of SIRs-INET-3/XAD-16 were further studied. The washed off LMW polymers had the Mn of 36,656, Mw of 40,310 and polydispersity coefficient of 1.10. The SIRs-INET-3/XAD-16 had shorter equilibrium time,less INET-3 loss and more Tm(III) adsorption capacity than the SIRs-INET-3/Pre-XAD-16. The PVA coated SIRs-INET-3/Pre-XAD-16 had less INET-3 loss and more Tm(III) adsorption capacity but longer equilibrium time than the uncoated SIRs-INET-3/Pre-XAD-16. The adsorption of RE(III) on the SIRsINET-3/XAD-16 followed the pseudo-second-order kinetic model. The Tm(III) accumulative adsorption amounts onto SIRs-INET-3/XAD-16 after eight extraction stages was 23.6 mg/g. The separation factors of adjacent heavy RE(III) β(Er/Ho), β(Tm/Er), β(Yb/Tm) and β(Lu/Yb) values were 1.76, 2.59, 2.56 and 1.19,respectively. The adsorbed Lu(III) onto the SIRs-INET-3/XAD-16 can be stripped completely by 1.0 mol/L H2SO4. 展开更多
关键词 (2 3-Dimethylbutyl)(2 4 4'-trimethylpentyl) phosphinic acid Solvent impregnated resins Adsorption Heavy rare earths
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Study of Transport and Separation of Rare Earth Ions through the Emulsion Liquid Membrane of Bis(2,4,4-trimethylpentyl)phosphinic Acid-Span 80-Toluene 被引量:3
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作者 李克安 邹长英 +1 位作者 姚晓华 童沈阳 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第4期241-245,共5页
It is indicated from a study of transport of rare earth ions through the emulsion liquid mem- brane of bis(2,4,4-trimethylpentyl)phosphinic acid-Span 80-toluene that transporting rare earth ions com- pletely and rapid... It is indicated from a study of transport of rare earth ions through the emulsion liquid mem- brane of bis(2,4,4-trimethylpentyl)phosphinic acid-Span 80-toluene that transporting rare earth ions com- pletely and rapidly was realized under the optimum experimental conditions:1.0×10^(-3)~3.0×10^(-3)mol/L bis(2,4,4-trimethylpentyl)phosphinic acid and 2%~4%(W/V)Span 80 in toluene solution as membrane phase,0.50~2.0 mol/L HCl as inner phase,rare earth ion solutions with pH 3.5~5.0 as outer phase.Ac- cording to the differences of transport behavior for rare earth ions,it is possible to separate rare earth ions from mixed solutions of rare earth ions by this liquid membrane system. 展开更多
关键词 Emulsion liquid membrane Ionic transport Rare earth separation Bis(2 4 4-trimethylpentyl)phosphinic acid(Cyanex 272)
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Extraction and Separation of Thorium and Ytterbium with Bis(2,4,4-Trimethylpentyl) Phosphinic Acid Using a Hollow Fiber Membrane Extractor 被引量:2
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作者 张凤君 罗芳 +1 位作者 李德谦 吴庸烈 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期262-264,共3页
The based membrane extraction of Th 4+ and Yb 3+ was studied in HBTMPP heptane using a hollow fibber membrane. The separation method of Th 4+ and Yb 3+ was proposed by kinetics competition. The se... The based membrane extraction of Th 4+ and Yb 3+ was studied in HBTMPP heptane using a hollow fibber membrane. The separation method of Th 4+ and Yb 3+ was proposed by kinetics competition. The separation operation of Th 4+ and Yb 3+ mixture was carried out by two successive extraction and stripping simultaneously. The concentration ratio of Th 4+ to Yb 3+ is 16 74 in the stripping solution. The recovery and purity of Th 4+ are 71 6% and 95 74% respectively. 展开更多
关键词 rare earths YTTERBIUM THORIUM hollow fibber membrane transfer bis(2 4 4 trimethylpentyl) phosphinic acid
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Selective extraction of In(Ⅲ),Ga(Ⅲ) and Zn(Ⅱ) using a novel extractant with phenylphosphinic acid 被引量:1
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作者 Yuji Sasaki Naoki Matsuo +1 位作者 Tatsuya Oshima Yoshinari Baba 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期232-236,共5页
A new extractant, [N,N-di(2-ethylhexyl)aminolmethylphenylphosphinic acid (DEAPP), was synthesized to de- velop the mutual separation techniques of In(Ⅲ), Ga(Ⅲ) and Zn(Ⅱ). The extraction selectivity for I... A new extractant, [N,N-di(2-ethylhexyl)aminolmethylphenylphosphinic acid (DEAPP), was synthesized to de- velop the mutual separation techniques of In(Ⅲ), Ga(Ⅲ) and Zn(Ⅱ). The extraction selectivity for In(Ⅲ), Ga(Ⅲ) and Zn(Ⅱ) with DEAPP was higher than that of the commercial phosphorus acid extractants such as D2EHPA and PC-88A. The extraction selectivity for metal ions in 1 mob L 1 aqueous ammonium nitrate solution with DEAPP was in the following order: In(Ⅲ) 〉 Ga(Ⅲ) 〉 Zn(Ⅱ). These selective extraction behaviors indicate that the amino moiety of DEAPP plays an important role in the mutual separation of ln(Ⅲ), Ga(Ⅲ) and Zn(ll). The extraction equilibria of In(Ⅲ), Ga(Ⅲ) and Zn(Ⅱ) with DEAPP ( = HR) were expressed by the following reactions: In3+ + 2(HR)2 InR3(HR) + 3H+, Ga3+ + 1.5(HR)2 + N- = GaR2(HR)(NO3) + 2H+, and Zn2+ 4- 2(HR)2 ZnR2 (HR) 2 determined 4- 2H+. The extraction equilibrium constants of In(Ⅲ), Ga(Ⅲ) and Zn(Ⅱ) with DEAPP were to be Kex, M = 1.7 × 104 [dm3.mol 1], 4.17 [(dm3.mol-1)s], and 1.55 × 10 2 [-], respectively. 展开更多
关键词 Liquid-liquid extraction phosphinic acid Indium(Ⅲ) Gallium(Ⅲ) Zinc(Ⅱ) Mutual separation Extraction equilibrium
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Cu-catalyzed arylation of phosphinic amide facilitated by (±)-trans-cyclohexane-1,2-diamine
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作者 Juan Li Song Lin Zhang +2 位作者 Chuan Zhou Tao Yao Fu Qing Xiang Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1033-1036,共4页
Cu-catalyzed cross coupling between phosphinic amides and aryl halides was accomplished for the first time by using (±)-trans-cyclohexane-1,2-diamine as the ligand. This reaction provided a novel approach for syn... Cu-catalyzed cross coupling between phosphinic amides and aryl halides was accomplished for the first time by using (±)-trans-cyclohexane-1,2-diamine as the ligand. This reaction provided a novel approach for synthesizing arylated phosphinic amides. Both kinetic measurement and theoretical calculation indicated that phosphinic amides were much less reactive than amides by about 10 times in Cu-catalyzed cross coupling. 展开更多
关键词 phosphinic amide Copper Catalyst Cross coupling
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Synthesis and Crystal Structure of α-(3-Phenylureido)-α-(2,4-Dichlorophenyl) Methyl Phenylphosphinic Acid
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作者 ZHOU Jia CHEN Ru-Yu(Institute of Elemento-Organic Chemistry, National Key Laboratory ofElemento-Organic Chemistry, Nankai University, Tainjin 300071)WANG Hong-Gen YAO Xin-Kan(Central Laboratory, Nankai University, Tianjin 300071) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第3期207-210,共4页
The crystal structure of a (3-phenylureido)-a (2, 4-dichlorophenyl)methyl phenylphosphinic acid, C20H17Cl2N2O3P, Mr= 435. 25,which was obtained bydesulphurisation of cis-3, 4-dipheny1-5- (2, 4-dichlorophenyl ) -1, 3, ... The crystal structure of a (3-phenylureido)-a (2, 4-dichlorophenyl)methyl phenylphosphinic acid, C20H17Cl2N2O3P, Mr= 435. 25,which was obtained bydesulphurisation of cis-3, 4-dipheny1-5- (2, 4-dichlorophenyl ) -1, 3, 4-diazaphospholidin2-thione-4-oxide utilizing Ag+ -H2O system in a yield of 89%, is reported. It crystallizes in orthorhombic space group Pca21 with a= 11. 286(2), b= 20. 601 (4) f c=8. 695(2)A, V= 2021 (1) A3, Z= 4, D.= 1. 430 g/cm3, p=4. 21 cm-1, F(000) =896.The final R factor is 0. 040 and Rw is 0. 045 for 946 unique observed reflections[I>3a(I)]. The result of X-ray analysis indicates that the molecules in the crystal are linkedtogether by the O(3 ) ...H (2d) - N (2d ) intermolecular hydrogen-bondings. 展开更多
关键词 crystal structure DESULPHURISATION reaction 1 3 4-diazaphospholidin-2-thione phosphinic acid derivative
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Separation of Tb^(3+) , Dy^(3+) , Ho^(3+) , Er^( 3+) with Solvent Impregnated Resins Containing Di-(2,4,4-trimethylpentyl) Phosphinic Acid
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作者 GUI Da li( General Research Institute for Nonferrous Metals, Beijing 100088, China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第3期185-185,共1页
Solvent impregnated resins (SIR) with di (2,4,4 trimethylpentyl)phosphinic acid (Cyanex 571) were studied by adsorption of the extractant into Amberlite XAD 4; XAD 7; XAD 1180 polymeric adsorbents. The results sh... Solvent impregnated resins (SIR) with di (2,4,4 trimethylpentyl)phosphinic acid (Cyanex 571) were studied by adsorption of the extractant into Amberlite XAD 4; XAD 7; XAD 1180 polymeric adsorbents. The results shas that Cyanex 571/XAD 7 impregnated resins containing extractant of 0 35~0 45 g·g -1 resin have a favorable extractive activity in HCl medium. The rare earths (Tb 3+ , Dy 3+ , Ho 3+ , Er 3+ ) are separated by using SIR as the column stationary phase. The better separation effect is obtained at lower load and slower elution rate. 展开更多
关键词 rare earths solvent impregnated resins di (2 4 4 trimethylpentyl)phosphinic acid SEPARATION
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SYNTHESES OF HINDERED ALKYL PHOSPHONATES AND PHOSPHONIC & PHOSPHINIC ACIDS
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作者 Wen Xiang HU Cheng Ye YUAN Shu Shen LI 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第3期167-170,共4页
A series of di-n-hexyl alkyl phosphonates with bulky substituent on phosphorus was synthesized by PTC P-alkylation using crown ether.Upon saponification of the resulting di-n-hexyl alkylphosphonates in the presence of... A series of di-n-hexyl alkyl phosphonates with bulky substituent on phosphorus was synthesized by PTC P-alkylation using crown ether.Upon saponification of the resulting di-n-hexyl alkylphosphonates in the presence of crown ether or quaternary ammonium halide, corresponding mono-hexyl esters of alkyl phosphonic acids were prepared.Ultrasonic wave, as we found, can catalyze the reaction between dialkyl phosphite & metallic sodium and hydrolysis of dihexyl alkyl phosphonates.A series of di-t-alkyl phosphinic acids were synthesized by the reaction of Grignard reagent with PCl_3 followed by oxidation with 30% H_2O_2.It was found that the reaction between dibutyl phosphite and Grignard reagent of t-alkyl chloride is a new synthetic method for the preparation of mono-esters of highly hindered alkyl phosphonic acids. 展开更多
关键词 SYNTHESES OF HINDERED ALKYL PHOSPHONATES AND PHOSPHONIC phosphinic ACIDS
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Study on the Borylation of β-C Positions of Aryl Olefins Catalyzed by Copper Organophosphorus Complexes
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作者 Du Shunli Wang Yaya +2 位作者 Guo Jiaming Xu Xuewei Peng Xinhua 《有机化学》 北大核心 2025年第7期2435-2443,共9页
Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron... Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products. 展开更多
关键词 arylenes bis(pinacolato)diboron copper organic phosphine complex hydrogenative borylation reduction boron dehydrogenation oxidation
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Pd-catalyzed enantioselective and regioselective asymmetric hydrophosphorylation and hydrophosphinylation of enynes
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作者 Yanxin Jiang Kwai Wun Cheng +1 位作者 Zhiping Yang Jun(Joelle)Wang 《Chinese Chemical Letters》 2025年第5期231-236,共6页
The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed fo... The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed for the highly selective synthesis of P-stereogenic alkenylphosphinates and alkenylphosphine oxides via conjugate addition of enynes.Notably,this methodology is suitable for both phosphine oxide and phosphinate nucleophiles,providing a versatile approach for the construction of diverse P-chiral organophosphosphorus compound. 展开更多
关键词 Phosphine ENYNE Pd catalyst P-chirality Asymmetric catalysis
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Robust metal nanoclusters for electrocatalytic synthesis
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作者 Jingjing Zhang Xinrui Gu Gao Li 《Chinese Journal of Structural Chemistry》 2025年第8期4-5,共2页
Ligand-stabilized metal nanoclusters with atomic precision have garnered significant attention for applications in catalysis,biomedicine,and nanoelectronics due to their tunable structures and unique physicochemical p... Ligand-stabilized metal nanoclusters with atomic precision have garnered significant attention for applications in catalysis,biomedicine,and nanoelectronics due to their tunable structures and unique physicochemical properties[1-3].While transition metals such as Au,Ag,Pt,and Pd dominate the core composition,surface ligands are predominantly limited to phosphines,thiols,alkynes,and carbenes.Among these,N-heterocyclic carbenes(NHCs)have emerged as a superior ligand class due to their dual capacity for strongσ-donation andπ-back bonding,which stabilizes diverse metal oxidation states and enhances metal-ligand interactions.Notably,NHC-protected clusters exhibit exceptional thermal stability attributed to CH-π/π-πinteractions and enlarged HOMO-LUMO gaps compared to thiol or phosphine analogues.Despite progress,synthetic limitations persist due to NHCs'sensitivity under harsh conditions.Current methods rely on direct reduction of metal-carbene precursors or ligand exchange reactions,with heterogeneous NHC-capped systems remaining unexplored. 展开更多
关键词 PHOSPHINES atomic precision ligand stabilized nanoclusters electrocatalytic synthesis transition metals ALKYNES metal nanoclusters THIOLS
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Cobalt pincer complex-catalyzed highly enantioselective hydrogenation of quinoxalines
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作者 Minghui Zhang Na Zhang +4 位作者 Qian Zhao Chao Wang Alexander Steiner Jianliang Xiao Weijun Tang 《Chinese Chemical Letters》 2025年第4期144-147,共4页
A cobalt pincer complex bearing both P and C-stereogenic centers has been designed and synthesized,allowing for the development of the first cobalt-catalyzed asymmetric hydrogenation of quinoxalines under relatively m... A cobalt pincer complex bearing both P and C-stereogenic centers has been designed and synthesized,allowing for the development of the first cobalt-catalyzed asymmetric hydrogenation of quinoxalines under relatively mild conditions.Valuable chiral 1,2,3,4-tetrahydroquinoxalines could be obtained with high yields and excellent enantioselectivities(35 examples,up to>99%ee). 展开更多
关键词 Cobalt catalysis Pincer PNN ligand Enantioselective hydrogenation Chiral tetrahydroquinoxaline Chiral phosphine
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Recent advances in phosphine-mediated sequential annulations
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作者 Xuling Pan Wei Cai You Huang 《Chinese Chemical Letters》 2025年第5期32-51,共20页
Polycyclic compounds are widely found in natural products and drug molecules with important biological activities,which attracted the attention of many chemists.Phosphine-catalyzed nucleophilic addition is one of the ... Polycyclic compounds are widely found in natural products and drug molecules with important biological activities,which attracted the attention of many chemists.Phosphine-catalyzed nucleophilic addition is one of the most powerful tools for the construction of various cyclic compounds with the advantages of atom economy,mild reaction conditions and simplicity of operation.Allenolates,Morita−Baylis−Hillman(MBH)alcohols and their derivatives(MBHADs),electron-deficient olefins and alkynes are very efficient substrates in phosphine mediated annulations,which formed many phosphonium species such asβ-phosphonium enolates,β-phosphonium dienolates and vinyl phosphonium ylides as intermediates.This review describes the reactivities of these phosphonium zwitterions and summarizes the synthesis of polycycle compounds through phosphine-mediated intramolecular and intermolecular sequential annulations.Thus,a systematic summary of the research process based on the phosphine-mediated sequential annulations of allenolates,MBH alcohols and MBHADs,electron-deficient olefins and alkynes are presented in Chapters 2-6,respectively. 展开更多
关键词 Phosphine catalysis Sequential annulations Polycyclic compounds Synthetic methods
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2D coordination polymers of transition metals as catalysts for oxygen evolution reaction
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作者 Mikhail N.Khrizanforov Anastasiia P.Samorodnova +5 位作者 Ilya A.Bezkishko Radis R.Gainullin Kirill V.Kholin Aidar T.Gubaidullin Ruslan P.Shekurov Vasili A.Miluykov 《Materials Reports(Energy)》 2025年第2期77-85,I0002,共10页
The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic... The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic study on isostructural 2D coordination polymers(CPs)based on 1,10-ferrocenediyl-bis(H-phosphinic)acid,with cobalt,manganese,and cadmium metals as electrocatalysts for OER.These polymers were synthesized via a facile solution reaction,yielding crystalline materials with excellent structural integrity.The electrocatalytic performance of CPs composites,prepared with carbon and phosphonium ionic liquid,was evaluated in 0.1 M KOH using a three-electrode system.Notably,the Co-and Cd-based CPs demonstrated exceptional OER activity,achieving an overpotential as low as 236–255 mV at 10 mA cm^(-2),surpassing those of many previously reported CP-based OER catalysts.Furthermore,these materials exhibited high stability over prolonged electrolysis,maintaining their activity without significant degradation.This work not only introduces a new class of ferrocenyl phosphinatebased CPs as highly active and durable OER catalysts but also provides valuable insights into their structureactivity relationships,paving the way for future advancements in electrocatalysis. 展开更多
关键词 Oxygen evolution reaction 2D coordination polymers Ferrocenyl phosphinate ligands ELECTROCATALYSIS Water splitting Surface morphology OVERPOTENTIAL Catalytic stability
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Diverse synthesis of bridged bicyclo[3.2.1]octa-2,6-diene and tricyclo[3.2.1.0^(2,7)]oct-3-ene frameworks via stepwise cascade reactions
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作者 Ze-Hong Zheng Mu-Qiu Chen +6 位作者 Jin Zhou Jie Wang Yan-Rong Wei Cheng Peng Gu Zhan Qian-Qian Yang Bo Han 《Chinese Chemical Letters》 2025年第12期212-217,共6页
Strained bridged rings bicyclo[3.2.1]octane and tricyclo[3.2.1.0^(2,7)]octane are prevalent in natural products known for their significant biological activities.However,strategies for efficiently synthesizing these c... Strained bridged rings bicyclo[3.2.1]octane and tricyclo[3.2.1.0^(2,7)]octane are prevalent in natural products known for their significant biological activities.However,strategies for efficiently synthesizing these complex frameworks from simple starting materials via de novo synthesis remain underexplored.This article presents an efficient strategy that combines phosphine catalysis and photocatalysis to execute a stepwise tandem reaction involving allenoates and α-cyano cinnamaldehydes,including[3+2]cyclization,[5+2]cyclization,acyl transfer,and decarboxylation reactions,synthesizing a series of functional bicyclo[3.2.1]octa-2,6-diene and tricyclo[3.2.1.0^(2,7)]oct-3-ene skeleton derivatives with excellent chemoselectivity demonstrated throughout the process.Meanwhile,the reaction can also be performed via a onepot,scalable phosphine/photocatalytic cascade process,efficiently yielding the bridged products which can serve as versatile intermediates for further applications. 展开更多
关键词 ALLENOATE Bridged bicyclo[3.2.1]octa-2 6-diene frameworks Tricyclo[3.2.1.02 7]oct–3-ene frameworks Phosphine catalysis Di-π-methane rearrangement reaction
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Effect of lengthening alkyl spacer on hydroformylation performance of tethered-phosphine modified Rh/SiO_2 catalyst 被引量:5
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作者 刘佳 严丽 +2 位作者 姜淼 李存耀 丁云杰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第2期268-272,共5页
Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-ph... Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-phospine,promoted the formation of active species and enhanced the activity of hydroformylation over other tethered-phosphine modified Rh/SiO2 catalysts. 展开更多
关键词 Tethered phosphine Chain length RHODIUM Silica HYDROFORMYLATION
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A preliminary study of polymer inclusion membrane for lutetium(Ⅲ)separation and membrane regeneration 被引量:3
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作者 Siyan Huang Ji Chen Dan Zou 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第10期1256-1263,I0004,共9页
This paper reports on the selective transport of Lu(Ⅲ)from La(III)and Sm(III)through a polymer inclusion membrane(PIM)composed of 40 wt%di(2-ethylhexyl)phosphinic acid(P227)and 60 wt%poly(vinylidene fluoride)(PVDF).B... This paper reports on the selective transport of Lu(Ⅲ)from La(III)and Sm(III)through a polymer inclusion membrane(PIM)composed of 40 wt%di(2-ethylhexyl)phosphinic acid(P227)and 60 wt%poly(vinylidene fluoride)(PVDF).Basically,the changes in surface morphology,thickness and water contact angle of this PVDF-based PIM containing P227(P227@PVDF PIM)with different polymer concentrations were investigated.By solvent extraction experiments,it is found that Lu(Ⅲ)can be selectively extracted from La(Ⅲ)and Sm(Ⅲ)at pH 1.5 in hydrochloric acid solution.According to this result,P227@PVDF PIM was used to selectively transport Lu(Ⅲ)from hydrochloric acid feed solution containing similar concentration of La(Ⅲ)and Sm(Ⅲ).The recovery factor of Lu(III)is 91% after 36 h,and about 5%of Sm(Ⅲ)was also transported through the PIM.The concentration of La(III)in the feed solution and the stripping solution does not change.Furthermore,to overcome the ubiquitous decline of transport efficiency caused by the loss of carrier or the damage of membrane structure after long-term use of PIMs,a process for regenerating PIMs was first proposed and implemented.By comparison of the regenerated PIM with the normal PIM,there is almost no difference in the SEM image,ATR-FTIR spectrum and Lu(III)transport efficiency.It is expected that P227@PVDF PIMs have the potential to be applied to the grouped separation of rare earth elements(REEs),and this study also can be as an inspiration for the further study on the PIMs regeneration process. 展开更多
关键词 Polymer inclusion membrane(PIM) Di(2-ethylhexyl)phosphinic acid(P227) LUTETIUM Rare earths SEPARATION
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Ionic palladium complex as an efficient and recyclable catalyst for the carbonylative Sonogashira reaction 被引量:1
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作者 杨妲 王栋梁 +4 位作者 刘欢 赵小莉 路勇 赖时军 刘晔 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第3期405-411,共7页
The neutral palladium(Ⅱ) complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-imidazolyl]dichloropalladium(Ⅱ)(1A) ligated by thiazolylimidazolyl-based phosphine(L1) in which thiazolylimidazolyl acted as an... The neutral palladium(Ⅱ) complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-imidazolyl]dichloropalladium(Ⅱ)(1A) ligated by thiazolylimidazolyl-based phosphine(L1) in which thiazolylimidazolyl acted as an S- and N-donor provider with weak coordinating nature,and the ionic complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-3-methylimidazolium]dichloropalladium(Ⅱ) trifluoromethanesulfonate(2A) ligated by thiazolylimidazolium-based phosphine(L2) after quaternization of L1 using methyl trifluoromethanesulphonate were synthesized.It was found that the introduced positive charges and strong electron-withdrawing effect in 2A not only led to changes in the configuration and structural stability of the complex,but also lowered its catalytic performance in carbonylative Sonogashira reactions.These effects reveal the important role of the N-donor in 1A.In addition,as an ionic palladium complex,2A combined with the room-temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate could be recycled eight times as the catalyst in carbonylative Sonogashira reactions without detectable metal leaching. 展开更多
关键词 Ionic phosphine ligand Palladium complex Carbonylative Sonogashira reaction Ionic liquid
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Killing Effect of Mixed Fumigation of Phosphine and Carbon Dioxide on Eggs of Lasioderma serricorne F. 被引量:2
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作者 彭涛 刘师伟 +2 位作者 谭琳 余兴江 郭年梅 《Agricultural Science & Technology》 CAS 2015年第12期2730-2732,共3页
[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a... [Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows: temperature of (27± 2) ℃, relatively humidity of (45±5)%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage. 展开更多
关键词 Mixed fumigation of phosphine and carbon dioxide Lasioderma serri- come F. Egg Fumigation time Mortality rate
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Poly(lactic acid)Nanocomposites with Improved Flame Retardancy and Impact Strength by Combining of Phosphinates and Organoclay 被引量:12
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作者 Lei Ye 任杰 +2 位作者 Shen-yang Cai Zhi-gang Wang 李建波 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第6期785-796,共12页
To minimize the loading level of the char-forming phosphorus based flame retardants in the poly(lactic acid) (PLA) with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blendin... To minimize the loading level of the char-forming phosphorus based flame retardants in the poly(lactic acid) (PLA) with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blending method incorporating organically modified montmorillonite (OMMT) and aluminium diethylphosphinate (A1Pi) additives. The influence of A1Pi and OMMT on flame retardancy and thermal stability of PLA was thoroughly investigated by means of the limiting oxygen index (LOI), UL94 test, cone calorimeter, X-ray diffraction (XRD), thermogravimetric analysis and scanning electronic microscopy (SEM). The experimental results show that the PLA/A1Pi/OMMT system has excellent fire retardancy. The LOI value increases from 19% for pristine PLA to 28% for the flame-retarded PLA. Cone calorimeter analysis of the PLA/A1Pi/OMMT exhibits a reduction in the peak heat release rate values by 26.2%. Thermogravimetric analysis and SEM of cone calorimeter residues indicate that OMMT significantly enhances the thermal stability, promotes char-forming and suppresses the melt dripping. The research of this study implies that the combining of the flame retardant and organoclay results in a synergistic effect. In addition, the flame-retarded PLA nanocomposite also exhibits notable increase in the impact strength and the elongation at break. 展开更多
关键词 Polylactic acid Flame retardancy NANOCOMPOSITE PHOSPHINATES Montmorillonite.
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