L-Butyl-3-methylimidazolium hexafluorophosphate bmim

This structural change is suppressed by the addition of tetrahydrothiophene (THT)19b. It prevents the formation of polymethylene zinc, i.e. (—CH2Zn—) . Without THT, a solution of 3 in THF yields polymethylene zinc at 60 °C. Monomeric bis(iodozincio)methane (3) is much more active for methylenation as compared to polymethylene zinc. As shown in Table 3 (entry 3), the addition of THT to the reaction mixture at 60 °C improved the yield of the alkene dramatically. Practically, however, its stinking property makes the experimental procedure in large scale uncomfortable. Fortunately, an ionic Uquid, l-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]), plays the same role. Ionic liquid also stabilizes the monomeric structure of 3 even at 60 °C and maintains it during the reaction at the same temperature. The method can be applied to various ketones as shown in Scheme 14.4... 

Recently, Yao showed that osmium tetroxide could be immobilized in an ionic liquid. The recyclability of osmium tetroxide was improved by the addition of DMAP. Both the catalyst and the ionic liquid were reused in six consecutive runs without significant reduction in yield [47]. Dihydroxylations in a solvent mixture of l-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6), tert-butanol, and water with 0s04 (2 mol%), DMAP (2.4 mol%), and NMO (1.1 equivalents) as cooxidant afforded diols in good yield (73-99% depending... 

Gas solubility data have also been measured by other authors, e.g., Henry coefficients for CO2 and CH4 in l-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6] have been determined at 298 K. In Table 2, the Henry coefficients for the two gases are given together with the values in NMP As can be seen from Table 2, much better separation factors (selectivities) are obtained for [BMIM][PFg] than for NMP and in comparison to EMIM BTI, the capacity is higher. From the results shown in Figure 7 and listed in Tables 1 and 2, it can be concluded that ionic liquids may be suitable absorbents for absorption processes. The removal of the sour gas CO2 from natural gas is only one example. 

Study on the equilibrium conversion of reversible reactions in CO2/IL mixed solvents is a new and interesting topic. The conversion of some reactions may be tuned effectively by changing operation conditions. The transesterification between isoamyl acetate and ethanol in supercritical SC CO2, l- -butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF(,), and in CO2/[bmim]PF6 mixed solvent was studied at 65.0°C and different pressures. 

The moisture- and air-stable ionic liquids, l-butyl-3-methylimidazolium tetra-lluoroborate [bmim]BF and l-butyl-3-methylimidazolium hexafluorophosphate [bmim]PFg, were used as green recyclable alternatives to volatile organic solvents for the ethylenediaimnonium diacetate-catalyzed Knoevenagel condensation between aldehydes or ketones with active methylene compounds. As described by Su et al. [57], the ionic hquids containing a catalyst were recycled several times without decrease in yields and reaction rates. In the case of 2-hydroxybenzaldehyde, the reactions led to the formation of 3-substituted coumarin derivatives in high yields of up to 95% (Scheme 17.11). When ethyl cyanoacetate was used, 2-imino-27f-l-benzopyran-3-carboxyhc acid ethyl ester was formed. 

Shamsipur et al. prepared a robust and effective catalase (CAT)-nanocomposite film modified-glassy carbon electrode using multiwalled carbon nanotubes (MWCNTs) and a room temperature ionic liquid, l-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]), by a layer-by-layer self-assembly method [21]. The ionic liquid assembled... 

Example 6.6 The Heck reaction, coupling aryl halides with a vinyl group, is promoted by microwaves and in situ prepared Pd(II) complex with V(ortho-to y )j, ligand in ionic liquid l-butyl-3-methylimidazolium hexafluorophosphate (bmim) [30]. 

Structure and Dynamics of a Room Temperature Ionic Liquid Ab Initio Molecular Dynamics Simulation Studies of l- -Butyl-3-methylimidazolium Hexafluorophosphate ([bmim][PF ]) and the [bmim][PF ]-C02 Mixture. 

PRACTICE EXAMPLE B Ionic liquids (ILs) are salts with relatively low melting points and vapor pressures. Because of their low volatilities, chemists continue to investigate the potential of ILs as safer and "greener" solvents. l-Butyl-3-methylimidazolium hexafluorophosphate, [BMIM][PF6], is a viscous, colorless, hydrophobic, and insoluble ionic liquid with a molar mass of 284.1 g/mol and a density of 1.38 g/mL. In a solution of [BMIM][PF6] and carbon dioxide at 8 MPa, the mole fraction of CO2 is 0.60. What is the solution concentration expressed as the (a) molarity of carbon dioxide and (b) molality of carbon dioxide Assume that there is no volume change when CO2 is added to [BMIM][PF6]. 

Figure 4.2-1 shows the calculated ab initio molecular structure of the ionic liquid [BMIM][PFg] (l-butyl-3-methylimidazolium hexafluorophosphate). 

The advantage of the stoichiometric technique is that it is extremely simple. Care has to be taken to remove all gases dissolved in the IL sample initially, but this is easily accomplished because one does not have to worry about volatilization of the IL sample when the sample chamber is evacuated. The disadvantage of this technique is that it requires relatively large amounts of ILs to obtain accurate measurements for gases that are only sparingly soluble. At ambient temperature and pressure, for instance, 10 cm of l-n-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) would take up only 0.2 cm of a gas with a Henry s law constant of... 

Bhargava, B.L., and Balasubramanian, S., Insights into the structure and dynamics of a room-temperature ionic liquid Ab initio molecular dynamics simulation studies of l-n-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PFj]) and the [bmim][PFj]-C02 mixture, /. Phys. Chem. B, 111, 4477-4487, 2007. 

In bmim PF6, l-butyl-3-methylimidazolium hexafluorophosphate Howarth, J. James, P Dai, J. Tetrahedron Lett. 2001, 42, 7517. 

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