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1.
Summary. Symmetric dibenzyl sulfones were synthesized in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) at 100°C from various benzyl chlorides and sodium dithionite in moderate yields. 相似文献
2.
Symmetric dibenzyl sulfones were synthesized in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) at 100°C from various benzyl chlorides and sodium dithionite in moderate yields. 相似文献
3.
Abdol R. Hajipour Majid Mostafavi Arnold E. Ruoho 《Monatshefte für Chemie / Chemical Monthly》2007,138(6):569-572
Summary. A straightforward and effective procedure for the deprotection of thioacetals to the corresponding carbonyl compounds using
potassium persulfate and the ionic liquid [bmim]Br under solvent-free conditions is reported. A variety of aliphatic and aromatic 1,3-dithiolanes or 1,3-dithanes was deprotected
to the corresponding carbonyl derivatives by this procedure. 相似文献
4.
Iveta Kmentová Battsengel Gotov Vladimír Gajda Štefan Toma 《Monatshefte für Chemie / Chemical Monthly》2003,134(4):545-549
Summary. The Sonogashira reaction of iodobenzene with phenylacetylene in several room temperature ionic liquids was studied. A regeneration of the
catalytical system immobilized in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6) has been also investigated. The reactivity of different iodoarenes with terminal alkynes in [bmim]PF6 was studied as well.
Corresponding author. E-mail: toma@fns.uniba.sk
Received September 2, 2002; accepted September 9, 2002 相似文献
5.
6.
Mária Meiarová Katarína Hubinská tefan Toma Burkhard Koch Albrecht Berkessel 《Monatshefte für Chemie / Chemical Monthly》2007,138(11):1181-1186
Summary.
N-Toluensulfonyl-l-prolin amide was tested as catalyst in the enantioselective Michael addition of carbonyl compounds to (E)-β-nitrostyrene in nine ionic liquids under different reaction conditions. The reaction rates and enantioselectivities were
strongly dependent on the ionic liquids. Change of enantioselectivity was observed too and it is attributed to both the cation
and the anion of ionic liquid. The best yields (up to 98%) and enantioselectivity (70% ee) of product were obtained in a basic ionic liquid [bmim]BF4 at room temperature. 相似文献
7.
Mária Me?iarová Katarína Hubinská ?tefan Toma Burkhard Koch Albrecht Berkessel 《Monatshefte für Chemie / Chemical Monthly》2007,14(1):1181-1186
N-Toluensulfonyl-l-prolin amide was tested as catalyst in the enantioselective Michael addition of carbonyl compounds to (E)-β-nitrostyrene in nine ionic liquids under different reaction conditions. The reaction rates and enantioselectivities were
strongly dependent on the ionic liquids. Change of enantioselectivity was observed too and it is attributed to both the cation
and the anion of ionic liquid. The best yields (up to 98%) and enantioselectivity (70% ee) of product were obtained in a basic ionic liquid [bmim]BF4 at room temperature. 相似文献
8.
Degradation of imidazolium ionic liquid, [bmim+][TFSA−] and iodide solution of [bmim+][TFSA−] by UV-laser irradiation has been studied through ground-state absorption and transient absorption spectroscopy. We found that excited state [bmim+]* undergoes degradation efficiently. 相似文献
9.
Three series of N-arylquinoline derivatives were synthesized by the three-component reactions of arylaldehyde, 3-arylamino-5,5-dimethylcyclohex-2-enone, and active methylene compounds including malononitrile, meldrum's acid, and 1,3-indenedione in ionic liquid [bmim+][BF4−] at 90 °C. 相似文献
10.
A series of azo compounds, N-aryl-2-phenyldiazenecarboxamides, and 4-substituted-1,2,4-triazoline-3,5-diones, were synthesized using Magtrieve™, a magnetically
retrievable and recyclable oxidant, in the ionic liquid [bmim][Br] under neutral condition. This procedure has several advantages, such as greenness, mild reactions, simple manipulation,
and reusability of reagent and solvent. 相似文献
11.
Baixiang Du Gan Cai Bo Zhao Xiangxue Meng Xiangshan Wang Yuling Li 《Research on Chemical Intermediates》2013,39(3):1323-1333
A series of 3,4-dihydro-12-phenyl-2H-benzo[b]xanthene-1,6,11(12H)-trione derivatives have been synthesized in high yields in the presence of ionic liquid [bmim+]Br?. The reaction work-up is simple and the ionic liquid can be easily separated from the product and reused. 相似文献
12.
Ahmad Shaabani Ali Hossein Rezayan Marjan Heidary Afshin Sarvary 《Monatshefte für Chemie / Chemical Monthly》2008,31(11):1471-1474
1-Butyl-3-methyl-imidazolium chloride ([bmim]Cl) in the absence of any catalyst mediated the selective deprotection of benzyl and phenyl trimethylsilyl (TMS) ethers to the corresponding alcohols and phenol in good yields at room temperature even in presence of alkyl silyl ethers.
The work-up of reactions is very simple and the products do not require further purification. The ionic liquid (IL) can be
recycled and reused for several runs without any significant loss of activity. 相似文献
13.
An imidazolium tosylate salt as efficient and recyclable catalyst for acetylation in an ionic liquid
A novel non-metallic salt, 1-butyl-3-methylimidazolium tosylate ([bmim][OTs]) dissolved in the ambient temperature ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]), was found to be the efficient catalyst for acetylation with the advantages of good recyclability, avoidance of metal contamination,
mild reaction conditions, and wide availability for substrates (alcohols, phenols, and amines), could completely replace organic
bases, metal Lewis acids, or metallic triflates to fulfill acetylation by a nucleophilic catalytic mechanism, which was supported by 13C NMR analysis.
Correspondence: Ye Liu, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Chemistry Department of East China
Normal University, Shanghai 200062, China. 相似文献
14.
RhTp(cod) ( 1 ) and RhBp(cod) ( 2 ), almost inactive in CH2Cl2, became good catalysts of phenylacetylene polymerization in ionic liquids ([bmim]Cl, [bmim]BF4: bmim = 1‐butyl‐3‐methylimidazolium, [mokt]BF4: mokt = 1‐methyl‐3‐oktylimidazolium, [bumepy]BF4: 1‐butyl‐4‐methylpyridinium) and in CH2Cl2 in the presence of tetraammonium halides ([R4N]X, R = Bu, Et; X = Cl, Br). The highest yields of polyphenylacetylene with catalyst 1 were obtained in [bmim]Cl at 65°C (64% after 2 h) and in [mokt]BF4 at 20°C (56% after 24 h). In alcohols (CH3OH, (CH3)2CHOH, (CH3)3COH) as solvents, up to 100% of the polymer was produced. When a mixture of an ionic liquid and CH3OH was used as the reaction medium, the polymer yield was similar to the yield achieved in an ionic liquid only, but the molecular weight increased remarkably. Tetraammonium salts, [R4N]X, are co‐catalysts for 1 , and the yield of the polymer increased in the order [Et4N]Br < [Bu4N]Br < [Et4N]Cl < [Bu4N]Cl. Polymers with molecular weights from 6900 to 38 800 Da were obtained with catalyst 2 in [R4N]Br or [R4N]Cl, whereas in ionic liquids ([bmim]Cl, [bmim]BF4) the corresponding molecular weights were higher, from 51 300 to 60 300 Da. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
15.
A series of azo compounds, N-aryl-2-phenyldiazenecarboxamides, and 4-substituted-1,2,4-triazoline-3,5-diones, were synthesized using Magtrieve™, a magnetically
retrievable and recyclable oxidant, in the ionic liquid [bmim][Br] under neutral condition. This procedure has several advantages, such as greenness, mild reactions, simple manipulation,
and reusability of reagent and solvent.
Correspondence: Yanqing Peng, Shanghai Key Laboratory of Chemical Biology, Institute of Pesticides and Pharmaceuticals, East
China University of Science and Technology, Shanghai 200237, China. 相似文献
16.
Ahmad Shaabani Ali Hossein Rezayan Marjan Heidary Afshin Sarvary 《Monatshefte für Chemie / Chemical Monthly》2008,139(12):1471-1474
1-Butyl-3-methyl-imidazolium chloride ([bmim]Cl) in the absence of any catalyst mediated the selective deprotection of benzyl and phenyl trimethylsilyl (TMS) ethers to the corresponding alcohols and phenol in good yields at room temperature even in presence of alkyl silyl ethers.
The work-up of reactions is very simple and the products do not require further purification. The ionic liquid (IL) can be
recycled and reused for several runs without any significant loss of activity.
Correspondence: Ahmad Shaabani, Department of Chemistry, Shahid Beheshti University, PO Box 19396-4716, Tehran, Iran. 相似文献
17.
Kai Gong Dong Fang Hua-Lan Wang Zu-Liang Liu 《Monatshefte für Chemie / Chemical Monthly》2007,138(11):1195-1198
Summary. Three-component Mannich-type reaction of cyclohexanone, aromatic aldehydes, and aromatic amines was catalyzed by a basic functionalized ionic liquid,
1-butyl-3-methylimidazolium hydroxide ([bmim][OH]), at room temperature to give various β-amino carbonyl compounds in high yields. The ionic liquid, which is environmentally
friendly, can be recycled at least 5 times without significant loss of activity. 相似文献
18.
Yanqing Peng Gonghua Song Feifei Huang 《Monatshefte für Chemie / Chemical Monthly》2005,136(5):727-731
Summary. A clean and efficient method for the synthesis of 4H-pyran derivatives through the one-pot condensation of aromatic aldehydes, malononitriles, and -dicarbonyl compounds, using guanidine base tetramethylguanidine in [bmim][BF4] ionic liquid as a recyclable catalytic system, was described. 相似文献
19.
E. P. Grishina T. V. Vladimirova L. M. Ramenskaya K. S. Shilovskii 《Russian Journal of Electrochemistry》2007,43(2):234-237
Electrochemical oxidation of silver in the 1-butyl-3-methylimidazolium bromide ([BMIm]Br) ionic liquid is studied by cyclic voltammetry, chronopotentiometry, chronoammetry, and gravimetry. Two electrode processes irreversibly proceed on the silver electrode in the potential range studied: the formation of compound [BMIm]+[AgBr2]?, which is soluble in [BMIm]Br, and difficultly soluble AgBr. 相似文献
20.
Antonia P. de los Ríos Francisco J. Hernández-FernándezFrancisca Tomás-Alonso Manuel RubioDemetrio Gómez Gloria Víllora 《Journal of membrane science》2008
Previously, we reported the selective simultaneous separation of the substrates and products of a transesterification reaction (vinyl butyrate, 1-butanol, butyl butyrate, and butyric acid) through supported liquid membranes (SLMs) based on two ionic liquids (ILs): 1-butyl-3-methylimidazolium hexafluorophosphate, [bmim+][PF6−], and 1-octyl-3-methylimidazolium hexafluorophosphate, [omim+][PF6−]. The significant differences observed in the selectivity values, attributed to the different nature of the ionic liquid phase used, led us to further investigate this matter. 相似文献