- Ionic liquid-type crown ether as a novel medium for a liquid/liquid extraction of radioactive metal ion85Sr2+
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1,13-Dichloro-4,7,10-trioxatridecane (2-[2-(1-chloro-2-ethoxy)ethoxy]ethyl chloride) (3a) was synthesized by a chlorination of 1,13-dihydroxy-4,7,10- trioxatridecane (triethylene glycol). And it was treated with imidazole and sodium ethoxide to give the 1N,1N′(oxoethylene)-diimidazole (3b), which was then converted to ionic liquid-type crown ether (ILCE) 3 with a reaction with 1,9-dichloro-3,6-trioxaoctane (2a). Further, the anion of ILCE was exchanged by an anion-exchange method. Ultimately, we developed a very efficient synthetic pathway for ILCEs 1-4 which have various physical and chemical characteristics by a modification of the polyethylene glycol chain length and anions. 85Sr2+ was successfully extracted into the [(3,2)OEtIm][Cl] (3) phase, but it was not extracted into the [(2,2)OEtIm][Cl] (1), [(3,3)OEtIm][Cl] (2), and [(4,3)OEtIm][Cl] (4) phases. Copyright
- Sang, Hyun Park,Dorjnamjin, Demberelnyamba,Seung, Ho Jang,Myung, Woo Byun
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Read Online
- Crown ether type ionic liquid based on imidazole, benzimidazole and their derivatives
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The invention discloses a crown ether type ionic liquid based on imidazole, benzimidazole and their derivatives. Cations of the crown ether type ionic liquid are imidazole, benzimidazole and their derivatives; anions include neutral or alkaline mononuclear and multinuclear anions; the mononuclear anions include Cl-, Br-, BF4-, PF6-, CF3COO-, CF3SO2-, (CF3SO2)N- and OH-; the multinuclear anions include AlCl4-, FeCl3- CuCl3- and AuCl4-. In some reactions, the crown ether type ionic liquid has the advantages of high reaction rate, high conversion rate, high reaction selectivity, reusability of acatalytic system and the like. In addition, the crown ether type ionic liquid also has a potential application prospect in terms of solvent extraction, separation and purification of matters, recycling of waste macromolecular compounds, fuel cells and solar cells, extraction of industrial waste gas, dissolution of geological samples, separation and treatment of nuclear fuels and nuclear wastes andthe like.
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Paragraph 0072; 0073; 0074-0079
(2019/06/30)
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- Design of task-specific ionic liquids for catalytic conversion of CO 2 with aziridines under mild conditions
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A series of polyethylene glycol (PEG)-functionalized ionic liquids (ILs) were developed as recyclable and efficient catalysts for selective synthesis of 5-aryl-2-oxazolidinones from aziridines and CO2 without addition of any organic solvents or additives. In particular, high yields, chemo- and regio-selectivities of oxazolidinones were attained when BrDBNPEG 150DBNBr (DBN: 1,5-diazabicyclo[4.3.0]non-5-ene) was used as the catalyst, presumably due to activation of CO2 by the ether linkage in the PEG backbone, and stabilization of the ring-opened species of aziridine by the delocalized cation BrDBNPEG150DBN+. Furthermore, the catalyst could be reused for over four consecutive cycles without appreciable loss of catalytic activity and selectivity. The effects of catalyst structure and various reaction parameters on the catalytic performance were also investigated in detail. It was demonstrated that the catalyst worked well for a variety of aziridines producing the corresponding oxazolidinones in good yields and excellent regio-selectivities. Therefore, this solvent-free process could thus represent an environmentally friendly approach for ILs-catalyzed conversion of CO2 into value-added chemicals.
- Zhao, Ya-Nan,Yang, Zhen-Zhen,Luo, Si-Hang,He, Liang-Nian
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- Highly efficient conversion of carbon dioxide catalyzed by polyethylene glycol-functionalized basic ionic liquids
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A series of polyethylene glycol (PEG)-functionalized basic ionic liquids (ILs) were developed for efficient CO2 conversion into organic carbonates under mild conditions. In particular, BrTBDPEG150TBDBr was proven to be a highly efficient and recyclable catalyst for the synthesis of cyclic carbonates without utilization of any organic solvents or additives. This is presumably due to the activation of epoxide assisted by hydrogen bonding and activation of CO2 by the ether linkage in the PEG backbone or through the formation of carbamate species with the secondary amino group in the IL cation on the basis of in situ FT-IR study under CO2 pressure. In addition, the subsequent transesterification of cyclic carbonate e.g. ethylene carbonate (EC) with methanol to dimethyl carbonate (DMC) can also be effectively catalyzed by BrTBDPEG150TBDBr, thanks to the activation of methanol by the secondary and tertiary nitrogen in the IL to easily form CH 3O-, realizing a so-called "one-pot two-stage" access to DMC from CO2 without separation of cyclic carbonate by using one kind of single component catalyst. Therefore, this protocol represents a highly efficient and environmentally friendly example for catalytic conversion of CO2 into value-added chemicals such as DMC by employing PEG-functionalized basic ILs as catalysts.
- Yang, Zhen-Zhen,Zhao, Ya-Nan,He, Liang-Nian,Gao, Jian,Yin, Zhong-Shu
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experimental part
p. 519 - 527
(2012/03/27)
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- SYNTHESIS OF DIFUNCTIONAL OXYETHYLENE-BASED COMPOUNDS
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A method of reacting a toluenesulfonyl-terminated polyoxyethylene compound having the formula CH3—C6H4—SO2—(O—CH2—CH2)n—O—R1 with an ammonium salt having the formula NR24X to form a compound having the formula X—CH2—CH2—(O—CH2—CH2)n-1—R3. The value n is a positive integer. X is a halogen, cyanide, cyanate, thiocyanate, or azide. R1 is a terminating group. Each R2 is hydrogen or an alkyl group. —R3 is —O—R1 or —X.
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Page/Page column 2-3
(2009/07/25)
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- Practical use of NH4X salts for difunctional oxyethylene-based intermediates
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A series of tosyl functionalized oxyethylene-based organic compounds were selected to analyze the scope and efficiency of a general substitution method for conversion to difunctional, soluble oxyethylene based intermediates using readily available ammonium salts, glycols and commercially modified ethoxy-ethanols. Straightforward preparation, product purification and low cost reagents are particularly advantageous for compounds incorporating halides, thiocyanates and methoxy groups.
- Holmes, Brian T.,Snow, Arthur W.
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p. 4813 - 4815
(2008/02/05)
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- Ionic liquid type crown ether derivatives, method for preparing the same and method for isolating metal ions using the same
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Disclosed relates to an ionic liquid type crown ether derivative, expressed by Chemical Formula 1 below, for isolating metal ions, a method for preparing the same and a method for isolating selectively the metal ions using the cycle size of the same. The present invention can provide the ionic liquid type crown ether and isolate metal ions including radioactive isotopes efficiently using the same. Furthermore, the prevent invention provides crown ether valuably used as a recyclable and environment-friendly isolating medium by preparing crown ether of ionic liquid type. wherein m, n, X? and R are identical with those in the description.
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Page/Page column 6
(2008/06/13)
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- Crosslinked polysaccharide, obtained by crosslinking with substituted polyethylene glycol, as superabsorbant
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New crosslinked polysaccharides useful as absorbents or superabsorbents alone or in a mixture are obtained by reacting polysaccharides (preferably containing carboxylates groups) with at least one crosslinker selected in the group constituted by activated polyethylene glycols such as for example halogenated (Cl, Br, I), mesylated, tosylated, or triflated activated polyethylene glycols.
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- A safe and efficient procedure to prepare alkyl and alkoxyalkyl chlorides and dichlorides by catalytic decomposition of the corresponding alkyl and alkoxyalkyl chloroformates and bischloroformates with hexabutylguanidinium chloride
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Small amounts of hexabutylguanidinium chloride (0.01 mol%) decomposes pure chloroformates or bischloroformates with different lengths of carbon chains by a semicontinuous process to diminish run-away risk, leading to chloride compounds with high yield and purity.
- Violleau,Thiebaud,Borredon,Le Gars
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p. 367 - 373
(2007/10/03)
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- The halogen-mediated opening of epoxides in the presence of pyridine-containing macrocycles
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The ring opening of epoxides with elemental iodine and bromine in the presence of three pyridine-containing macrocyclic diamides as new catalysts affords vicinal iodo alcohols and bromo alcohols in high yields. This new procedure occurs regioselectively under mild conditions in various aprotic solvents. The catalysts are easily recovered and can be reused several times.
- Sharghi, Hashem,Niknam, Khodabakhsh,Pooyan, Maryam
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p. 6057 - 6064
(2007/10/03)
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- Synthesis of podands bearing aromatic end groups and complex formation with tropylium tetrafluoroborate in 1,2-dichloroethane
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A series of podands bearing phenyl, naphthyl and anthryl end groups were prepared and characterized. UV-visible spectrophotometry was used to investigate the host-guest chemistry of the podands in complexation with tropylium tetrafluoroborate in 1,2-dichloroethane. The results, are discussed and compared with those for previously studied systems containing crown ethers. The stability constants for these open-chain polyethers are in the range 5,1-8,4 dm3 mol-1, except for the podand having anthryl end groups [1,12 bis(anthryl-9)-2,5,8,11-tetraoxadodecane], which gives a 10-fold increase in the stability constant. Copyright
- Laemsae, Markku,Raitamaa, Kirsi,Pursiainen, Jouni
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p. 557 - 563
(2007/10/03)
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- Synthese de Systemes Macromoleculaires a Caractere Complexant Derives de la 1,3-Dihydrobenzimidazole-2-thione
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Synthesis of macrocyclic compound by reaction between an ethylene glycol and the 1,n-bis(2-mercapto benzimidazolyl) di (and tri) ethylene glycol have been realised under phase transfer catalysis conditions.The compounds have been studied by proton nuclear magnetic resonance, mass spectrometry, infrared and by microanalysis.
- Zniber, Rachid,Regragui, Mohamed,Achour, Redouane,Cherkaoul, Omar,Hajji, Ahmed Jalal El,Cherkaoui, Mohammed Zoubair
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p. 457 - 462
(2007/10/03)
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- The synthesis of novel crown ethers. Part I. Coumarin derivatives of crown ethers
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The synthesis and structural characterisation of coumarin derivatives of some macrocyclic ethers was reported. They were obtained from 1,2,3-trihydroxy and 1,2,4-trihydroxyphenols by reacting with ketoesters. The reaction of dihydroxy coumarins with dichlorides of polyglycols in potassium carbonate/DMF/water afforded the crown ethers in good yields.
- Bulut,Erk
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p. 1259 - 1263
(2007/10/02)
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- Process for the preparation of ether-containing chlorides
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Disclosed is a process for the preparation of ether-containing chlorides by reacting an ether-alcohol, ether-glycol or ether-polyglycol with a chlorinating agent such as thionyl chloride in the presence of a catalytic amount of a quaternary ammonium salt, the reaction being conducted at a temperature of about 25° C. to about 90° C.
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- Metal-assisted Reactions. Part 17. Ring-opening and Dimerization of Cyclic Ethers by Titanium Halides
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Reaction of TiCl4 or TiBr4 with a variety of cyclic ethers gives, predominantly, products resulting from simple ring-opening or from ring-opening with simultaneous condensation to dimeric species.The variations in yields of these two kinds of products might be correlated qualitatively with an initial formation of the complex TiX4*2E (X = Cl or Br; E = cyclic ether) in which the ethers were held in a cis or trans relationship.Although such a correlation might suggest that TiCl4 but not TiBr4 exerts a template effect on the condensation, stereochemical considerations of the reaction products indicate otherwise.TiCl3 and VCl3 do not give similar results and TiF4 gives no reaction.
- Delaney, Paul A.,Johnstone, Robert A. W.,Entwistle, Ian D.
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p. 1855 - 1860
(2007/10/02)
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- COMPLEXES OF LANTHANIDE IONS WITH THE CROWN ETHER 1,4,7,10,13,16-HEXAOXACYCLO-OCTADECANE
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The title crown ether forms three types of compound with lanthanide ions, (M=La-Nd), M4(NO3)12(crown)3 (M=La-Gd), and crown (M=Gd-Lu).Crystal structures of the first and third types have been determined by X-ray diffraction.The complex is orthorombic, space group Pbca, with a=12.249, b=15.618, c=21.852 Angstroem, and Z=8.Least-squares refinement using 3607 observed 1.5?(I)> intensity data has given R=0.0399.The lanthanum co-ordination comprises the six crown oxygens and two oxygens from each of the three bidentate nitrates molecule by O...HO bonds.The Gd-O bond lengths are 2.41-2.53(1) Angstroem for nitrato- and 2.30-2.46(1) Angstroem for water oxygens.
- Backer-Dirks, J. D. Julius,Cooke, James E.,Galas, Anita M. R.,Ghotra, Joginder S.,Gray, Colin J.,at all.
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p. 2191 - 2207
(2007/10/02)
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