Ionic liquid effect

Obviously, the check for protic impurities becomes crucial if the ionic liquid is to be used for applications in which protons are known to be active compounds. Eor some organic reactions, one has to be sure that an ionic liquid effect does not turn out to be a protic impurity effect at some later stage of the research ... [Pg.26]

Many transition metal-catalyzed reactions have already been studied in ionic liquids. In several cases, significant differences in activity and selectivity from their counterparts in conventional organic media have been observed (see Section 5.2.4). However, almost all attempts so far to explain the special reactivity of catalysts in ionic liquids have been based on product analysis. Even if it is correct to argue that a catalyst is more active because it produces more product, this is not the type of explanation that can help in the development of a more general understanding of what happens to a transition metal complex under catalytic conditions in a certain ionic liquid. Clearly, much more spectroscopic and analytical work is needed to provide better understanding of the nature of an active catalytic species in ionic liquids and to explain some of the observed ionic liquid effects on a rational, molecular level. [Pg.226]

Arce, A. et al.. Separation of benzene and hexane by solvent extraction with l-alkyl-3-methylimidazolium bis (trifluoromethyl)sulfonyl amide ionic liquids effect of the alkyl-substituent length, /. Phys Chem. B, 111, 4732,2007. [Pg.68]

Dharman MM, Choi H-J, Kim D-W et al (2011) Synthesis of cyclic carbonate through microwave irradiation using silica-supported ionic liquids Effect of variation in the silica support. Catal Today 164(1) 544—547... [Pg.52]

C jimHPFs] Mn(porphyrin) complex PhI(OAc)2 Epoxidation of styrene CH2C12 as co-solvent better results in presence of an ionic liquid effect of ionic liquid concentration and oxidant concentration studied products extracted with hexane catalyst active for at least 10 runs without significant decrease in activity MnTPPS4 is more active than MnTPPCl. [34] [35]... [Pg.101]

A main question - not yet really considered - concerns the inertness of ionic liquids. Not only are the anions potential ligands, especially for neutral and cationic metal complexes one has also to take into consideration what is known for cations like (imid)azolium formation of carbene complexes via deprotonation is a rather facile process especially if ligands of sufficient basicity are present, e. g., -OR, -NR2. Therefore, several of the impressive catalytic results [113] deserve mechanistic investigation to find out whether they are really limited to the ionic liquid effects. For example, solvent and complexation effects are likely to enhance one another in the Heck coupling reactions that were run in the presence of Structure 18, Scheme 11 [115]. [Pg.1364]

Jacquemin J, Husson P, Mayer V et al. (2007) High-pressure volumetric properties of imidazolium-based ionic liquids - effect of the anion. J Chem Eng Data 52 2204-2211... [Pg.210]

Weingartner H, Sasisanker P, Daguenet C et al (2007) The dielectric response of room-temperature ionic liquids effect of cation variation. J Phys Chem B 111 4775-4780... [Pg.31]

Hallett IP, Liotta CL, Ranieri G et al (2009) Chaige screening in the SN2 reaction of charged electrophiles and charged nucleophiles an ionic liquid effect. J Org Chem 74 1864—1868... [Pg.32]

Lau RM, Sorgedrager MJ, Carrea G, van Rantwijk F (2004) Dissolution of Candida antarctica lipase B in ionic liquids effects on structure and activity. Green Chem 6 483 87... [Pg.187]

Fujita K, Macfarlane DR, Forsyth M et al (2007) Solubility and stability of cytochrome c in hydrated ionic liquids effect of oxo acid residues and kosmotropicity. Biomacromolecules 8 2080-2086... [Pg.270]

Park MJ, Lee JK, Choi IS et al (2006) Covalent modification of multiwaUed carbon nanotubes with imidazolium-based ionic liquids effect of anions on solubility. Chem Mater 18 1546-1551... [Pg.429]

Uwari S, Khupse N, Kumar A (2008) Intramolecular Diels-Alder reaction in ionic liquids effect of ion-specific solvent friction. J Org Chem 73 9075-9083... [Pg.489]

Most discussion of solvent effects rely on the concept of solvent polarity (cf. Introduction of this book). The investigation of ionic liquid effect on chemical reactions is at the present time probably the most productive way to characterize these solvent polarity . A nice example is given by the Diels-Alder reaction of cyclopenta-... [Pg.661]

Ionic Liquid Effects on Reactions Proceeding through Isopolar and Radical Transition States... [Pg.268]

In conclusion, ionic liquids probably caimot be considered as polar solvents, nor as non-polar solvents, nor as polymeric matrixes. Their behavior arises from a fine balancing of entropic and enthalpic contributions that involve all of the interactions inside the ionic liquid and aU of the possible interactions between cations and/or anions and dissolved species. The ability of ionic liquids to affect reactivity is, therefore, much more complicated to rationalize and more parameters must be considered to explain the ionic liquid effect on reaction rate and selectivity than with molecular solvents. [Pg.290]

In the reaction using the Rh-sulfoxantphos catalyst without ionic liquid, the activity and selectivity decreased sharply after 5-10 h on stream, while the SILP system (a = 0.1) reached its maximum activity only after 30 h and maintained this level stable up to 60 h (i.e. TON > 2400) along with a high selectivity corresponding to a n/iso ratio of 21-23. It can also be deduced that the apparently negative ionic liquid effect on the catalyst activity measmed in the short time reactions can be explained by a delayed formation of the catalytically active species. [Pg.547]

A.P. de los Rfos, F.J. Hemandez-Femandez, F. Tomas-Alonso et al.. Stability studies of supported liquid membranes based on ionic liquids Effect of surrounding phase nature. Desalination 245 (2009) 776-782. [Pg.628]

Jacquemin, J., P. Husson, V. Mayer, and I. Cibulka. 2007. High-pressure volumetric properties of imidazohum-based ionic liquids Effect of the anion. Journal of Chemical and Engineering Data. 52, 2204. [Pg.336]

Ionic Liquid Effects on Surface Charge Density... [Pg.163]

Bou-Malham I, Bureau L (2010) Nanoconfined ionic liquids effect of surface charges on flow and molecular layering. Soft Matter 6(17) 4062 065. doi 10.1039/c0sm00377h... [Pg.219]

Ueno, K., Imaizumi, S., Hata, K. and Watanabe, M., Colloidal interaction in ionic liquids Effects of ionic structures and surface chemistry on rheology of silica colloidal dispersions, Langmuir 25, 825-831 (2009). [Pg.168]

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