2-methylimidazolium trifluoromethanesulfonate

TON= moles formic acid formed per mole of metal [DAMI] [TfD] = l,3-di(N,N-dimethylaminoethyl)-2-methylimidazolium trifluoromethanesulfonate NHC = N-heterocyclic carbine, Tp=hydrotris(pyrazolyl)borate. 

Recently, there has been considerable interest in developing molten salts that are less air and moisture sensitive. Melts such as l-methyl-3-butylimidazolium hexa-fluorophosphate [211], l-ethyl-3-methylimidazolium trifluoromethanesulfonate [212], and l-ethyl-3-methylimidazolium tetrafluoroborate [213] are reported to be hydro-phobic and stable under environmental conditions. In some cases, metal deposition from these electrolytes has been explored [214]. They possess a wide potential window and sufficient ionic conductivity to be considered for many electrochemical applications. Of course if one wishes to take advantage of their potential air stability, one loses the opportunity to work with the alkali and reactive metals. Further, since these ionic liquids are neutral and lack the adjustable Lewis acidity common to the chloroaluminates, the solubility of transition metal salts into these electrolytes may be limited. On a positive note, these electrolytes are significantly different from the chloroaluminates in that the supporting electrolyte is not intended to be electroactive. 

The typical in situ reduction of the precursor [lr(COD)Cl]2 by molecular hydrogen under the same reaction conditions have been also performed in 1-n-butyl-3-methylimidazolium trifluoromethanesulfonate (BMl-CFsSOs) and 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMl-BF [25]. The iridium nanoparticles prepared in BMTCF3SO3 and BM1-BF4 ILs, as previously observed with BM1-PF6, display irregular shapes with a monomodal size distribution (Figure 15.4). Mean diameters in the range of 2-3 nm were estimated with in situ TEM and small-angle X-ray scattering (SAXS) analyses of the lr(0) nanoparticles soluble in the ionic hquids, and by X-ray diffraction (XRD) of the isolated material. The mean diameters of iridium nanoparticles synthesized in the three ILs, as estimated by TEM, SAXS and XRD, are summarized in Table 15.1. 

Sekiguchi et al. [46] have reported the recycling and re-use of 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, [C2mim][OTf], after poly (pyrrole) synthesis by extraction of the unreacted monomer with chloroform. The ionic liquid was reused five times with little change in the growth CVs of the polymer. 

Kosmuiski. M., Granqvist, B., and Rosenholm, J.B.. Electrokinetics of anatase in l-ethyl-3-methylimidazolium trifluoromethanesulfonate. Colloids Surf. A, 254,179, 2005. 

Sekiguchi, K., Atobe, M., and Fuchigami, T. (2003). Electrooxidative polymerization of aromatic compounds in l-ethyl-3-methylimidazolium trifluoromethanesulfonate room-temperature ionic liquid./. Electroanal. Chem., 557, pp. 1-7. 

Catalytic oxidation of beech organosolv lignin in ionic liquid (l-ethyl-3-methylimidazolium trifluoromethanesulfonate) at 100°C and 8 MPa air in the presence of 20% Mn(N03)2 formed DMBQ 25 in 11.5% isolated yield and 21% selectivity. The amount of 25 formed under these conditions depended on the catalyst level. At 2% catalyst, the product slate shifted to a mixture of syringaldehyde, syringyl alcohol, and vanillin, with only trace amounts of DMBQ observed. The authors propose that DMBQ results from syringaldehyde oxidation [100]. 

Figure 21.7 Novel ionic liquids for CC column coating, (a) l-Benzyl-3-methylimidazolium trifluoromethanesulfonate [BzMIM][OTf]. (b) l-(4-Methoxyphenyl)-3-methylimidazolium trifluoromethanesulfonate [MeO-PhMIM][OTf], (c) Separation of polar/nonpolar mixture CHjClj (1), methyl caproate (2), octyl aldehyde (3), dodecane (4), octanol (5), tridecane (5), naphthalene (7), nitrobenzene (8), tetradecane (9), pentadecane (10), and octanoic acid (11). Conditions 80°C for 3min, 10°Cmin" to...

Mukai, T. and Nishikawa, K., Syntheses and crystal structures of two ionic liquids with halogen-bonding groups 4,5-dibromo- and 4,5-diiodo-l-butyl-3-methylimidazolium trifluoromethanesulfonates. Solid State Sci. 12 (5), 783-788 (2010). 

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