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Two 2,4,6-trimethylaniline-based trifuloromethanesulfonate (trifluoromethanesulfonate) salts were synthesized and characterized by single-crystal X-ray diffraction. N,2,4,6-Tetramethylanilinium trifluoromethanesulfonate, [C10H14NH2+][CF3O3S-] (1), was synthesized via methylation of 2,4,6-trimethylaniline. N-Isopropylidene-N,2,4,6-tetramethylanilinium trifluoromethanesulfonate, [C13H20N+][CF3O3S-] (2), was synthesized in a two-step reaction where the imine, N-isopropylidene-2,4,6-trimethylaniline, was first prepared via a dehydration reaction to form the Schiff base, followed by methylation using methyl trifluoromethanesulfonate to form the iminium ion. In compound 1, both hydrogen bonding and p-p interactions form the main intermolecular interactions. The primary interaction is a strong N--H...O hydrogen bond with the oxygen atoms of the trifluoromethanesulfonate anions bonded to the hydrogen atoms of the ammonium nitrogen atom to generate a one-dimensional chain. The [C10H14NH2+] cations form dimers where the benzene rings form a p-p interaction with a parallel-displaced geometry. The separation distance between the calculated centroids of the benzene rings is 3.9129 (8) Å, and the interplanar spacing and ring slippage between the dimers are 3.5156 (5) and 1.718 Å, respectively. For 2, the [C13H20N+] cations also form dimers as in 1, but with the benzene rings highly slipped. The distance between the calculated centroids of the benzene rings is 4.8937 (8) Å, and interplanar spacing and ring slippage are 3.3646 (5) and 3.553 Å, respectively. The major intermolecular interactions in 2 are instead a series of weaker C--H...O hydrogen bonds [C...O distances of 3.1723 (17), 3.3789 (18), and 3.3789 (18) Å], an interaction virtually absent in the structure of 1. Fluorine atoms are not involved in strong directional interactions in either structure. [ABSTRACT FROM AUTHOR]

Potassium hydrogen sulfate (KHSO4) and trifluoromethanesulfonic acid (CF3SO3H) were separately used as efficient catalysts for the one-pot three-component synthesis of a series of indazolophthalazinetriones from various aldehydes, dimedone, and 2,3-dihydrophthalazine-1,4-dione at 80°C under solvent-free conditions in good to excellent yields. It was found that trifluoromethanesulfonic acid is a more efficient catalyst than potassium hydrogen sulfate since CF3SO3H is a stronger acid than KHSO4, and the corresponding intermediate will probably be formed at a higher rate and be more stable. [ABSTRACT FROM AUTHOR]

Thermal analysis, X‐ray diffraction and temperature‐dependent IR spectroscopy were used to study the dehydration process of crystalline dl‐phenylglycinium trifluoromethanesulfonate monohydrate (PGTFH), C8H10NO2+·CF3SO3−·H2O. PGTFH dehydrates in one step centred at 353 K and crystallizes in the monoclinic space group C2/c, whereas the anhydrous compound (PGTF) crystallizes in the triclinic space group P. The dehydration process in PGTFH is preceded by a weakening of both the noncovalent aromatic–aromatic interactions and the packing contacts. This process is accompanied by the breakage of medium‐strength O—H...O hydrogen bonds between ions inside layers and a reorganization of the ions within the layers. This reorganization results in the formation of two different ion pairs (dl‐phenylglycinium trifluoromethanesulfonate) and the formation of a new hydrogen‐bond network. The dehydration process does not destroy the nature of the crystal structure. Both crystals, i.e. hydrated and anhydrous, have a layered structure, although the layers of each crystal are arranged somewhat differently. [ABSTRACT FROM AUTHOR]

This work presents a Zn/graphite dual-ion battery using natural graphite as the cathode and metallic zinc as the anode, with ionic liquid-based electrolyte. Upon charge, the Zn2+ cations deposit on the zinc anode, and the trifluoromethanesulfonate (TfO−) anions simultaneously intercalate into the graphite cathode; upon discharge, both the ions are released back into the electrolyte. The 0.2 M Zn(TfO)2/EMImTfO ionic liquid-based electrolyte exhibits a high electrochemical window of 2.8 V (vs. Zn2+/Zn) as well as a high conductivity of 7.3 ms cm−1. The deposition/stripping of zinc on a copper working electrode is systematically studied, which reveals that Zn2+ cations are mobile in the ionic liquid electrolyte, and zinc can be deposited and stripped in this electrolyte. The insertion/extraction of TfO− into/from graphite is also investigated, demonstrating a reversible process. At a current of 0.2 mA cm−2 and within the voltage of 0.8-2.8 V, the Zn/graphite dual-ion cells exhibit a high sloping discharge plateau within 1.8-2.4 V (corresponding to a medium voltage of about 2.0 V), a discharge capacity of 33.7 mAh g−1, and an energy density of 65.1 Wh kg−1; cells deliver a cyclability of 93.5% Coulombic efficiency for 100 cycles. The SEM image reveals that the zinc deposits are compact and dense, and uniformly distribute on anodes with an average grain size of about 200 nm, without the formation of dendrites. The use of high-safety electrolyte and low-cost electrode materials may enable this cell configuration to be a promising candidate for future energy storage systems. [ABSTRACT FROM AUTHOR]

In the present work, a new binary mixture system composed of the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([Emim][CF3SO3]) and propylene carbonate (PC) was prepared. The densities, dynamic viscosities, and electrical conductivities of ([Emim][CF3SO3] + PC) were measured over the whole concentration range (mole fractions of IL from 0 to 1) for temperatures from 288.15 to 353.15 K. The excess molar volumes (VE) and viscosity deviations (Δη) of the binary systems were calculated to characterize the volume contraction and intermolecular interactions in the mixture system, and both were correlated with the Redlich-Kister polynomial equation. The Vogel-Fulcher-Tamman equation was used to describe the temperature dependences of the dynamic viscosities and the electrical conductivities of the binary system. Further, density functional theory calculations were employed to obtain the structure, energy, and COSMO charge distributions of the cation and anion of the IL and the PC molecule, and the intermolecular interactions in the binary mixture system were evaluated. [ABSTRACT FROM AUTHOR]

Electrostatic interactions between localized integral charges make the stability and structure of highly charged small and rigid organics intriguing. Can σ/π-electron delocalization compensate reduced conformational freedom by lowering the repulsion between identical charges? The crystal structure of the title salt, C14H16N42+·2CF3SO3−, (2), is described and compared with that of the 2,2′′-bis(diphenylphosphanyl) derivative, (4). The conformations of the dications and their interactions with neighbouring trifluoromethanesulfonate anions are first analyzed from the standpoint of formal electrostatic effects. Neither cation exhibits any geometrical strain induced by the intrinsic repulsion between the positive charges. In contrast, the relative orientation of the imidazolium rings [ i.e. anti for (2) and syn for (4)] is controlled by different configurations of the interactions with the closest trifluoromethanesulfonate anions. The long-range arrangement is also found to be specific: beyond the formal electrostatic packing, C-H...O and C-H...F contacts have no definite `hydrogen-bond' character but allow the delineation of layers, which are either pleated or flat in the packing of (2) or (4), respectively. [ABSTRACT FROM AUTHOR]

Reaction of AgX (X−  =  NO2−and CF3SO3−) withC3-symmetricN,N′,N″-tris(2-pyridinylethyl)-1,3,5-benzenetricarboxamide (L) produces, respectively, an unusual nitrite-bridged 3-D coordination polymer, [Ag2(NO2)2L]·H2O, with trinodal 3,3,4-connectedtfanet topology and a unique 3-D coordination polymer, [Ag3L2](CF3SO3)3·CH2Cl2·4H2O, with sixfold interpenetrating uninodal 3-connectedthsnet topology. Nitrite anions are two kinds of chelating and bridging ligands, whereas trifluoromethanesulfonate anions are simple counteranions. Structure-related thermal behavior, anion exchangeability, and photoluminescence have been investigated. [ABSTRACT FROM PUBLISHER]

An ion-pair chromatographic method was developed on a reversed-phase silica-based monolithic column for the fast and simultaneous determination of trifluoroacetate (CF3COO−), trifluoromethanesulfonate (), tetrafluoroborate (), and hexafluorophosphate () organic and inorganic anions of ionic liquids. The analytes were separated using a mobile phase of tetrabutylammonium hydroxide–citric acid–acetonitrile on the Chromolith Speed ROD RP-18e column with direct conductivity detection. The effects of eluent, column temperature, and flow rate on the retention of anions were investigated. The experimental phenomenon was discussed according to ion-exchange and hydrophobic interaction mechanism in the separation. The optimized chromatographic conditions were selected. Under the optimal conditions, the baseline separation of CF3COO−,,, andwas achieved without any interference by other anions (Cl−, Br−, I−,,, and). The detection limit (S/N = 3) was 3.33, 0.58, 0.27, and 1.42 mg/L for CF3COO−,,, and, respectively. The method has been successfully applied to the determination of, CF3COO−,, andin ionic liquids. The spiked recoveries of the anions were from 100.1–104.4%. [ABSTRACT FROM AUTHOR]

A method of ion-pair chromatography was developed on a reversed-phase silica-based monolithic column for the fast and simultaneous determination of trifluoromethanesulfonate (CFSO) and p-toluenesulfonate (CHSO). The analysis was performed using a mobile phase of tetrabutylammonium hydroxide + citric acid + acetonitrile on the Chromolith Speed ROD RP-18e column with direct conductivity detection. The effects of the eluent, column temperature and flow rate on the retention of the anions were investigated. The experimental phenomenon was discussed according to hydrophobic interaction and ion-exchange mechanism in the separation. The optimized chromatographic conditions were selected. The optimized eluent for the separation consisted of 0.2 mmol L tetrabutylammonium hydroxide + 0.10 mmol L citric acid + 9% acetonitrile (pH 5.5). The flow rate was set at 6.0 mL min. The column temperature was 25 °C. Under the optimal conditions, the better separation of CFSO and CHSO was achieved without any interference by other anions (Cl, Br, I, NO, SO, ClO, BF and PF). The detection limit (S/N = 3) was 0.28 and 0.71 mg L for CFSO and CHSO, respectively. The method has been applied to the determination of CFSO and CHSO in ionic liquids. The spiked recoveries of CFSO and CHSO were 101.1 and 100.2%, respectively. [ABSTRACT FROM AUTHOR]

From extraction experiments and γ-activity measurements, the extraction constants corresponding to the general equilibrium Eu3+(aq) + 3 A−(nb) + L(nb) ⇔ EuL3+(nb) + A−(nb) taking place in the two-phase water–nitrobenzene system ( $$ {\text{A}}^{ - } = {\text{CF}}_{3} {\text{SO}}_{3}^{ - } $$; L = tetrakis(2-ethoxyethoxy)-tetra- p-tert-butylcalix[4]arene ( 1), tetraethyl p-tert-butylcalix[4]arene tetraacetate ( 2), p-tert-butylcalix[4]arene-tetrakis(N,N-diethylacetamide) ( 3), hexaethyl p-tert-butylcalix[6]arene hexaacetate ( 4), p-tert-butylcalix[6]arene-hexakis(N,N-diethylacetamide) ( 5); aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Further, the stability constants of the EuL3+ complexes in nitrobenzene saturated with water were calculated; they were found to increase in the series of 2 < 4 < 1 < 5 < 3. [ABSTRACT FROM AUTHOR]

An improved protocol for the large‐scale production of 1‐benzenesulfinyl piperidine and other sulfinamides is described. It is demonstrated that 1‐benzenesulfinyl pyrrolidine and N,N ‐diethyl benzenesulfinamide function analogously to 1‐benzenesulfinyl piperidine in the trifluoromethanesulfonic anhydride‐mediated activation of thioglycosides, and that their less crystalline nature enables them to be used at -78°C as opposed to the -60°C required to keep 1‐benzenesulfinyl piperidine in solution. N,N -Dicyclohexyl benzenesulfinamide does not activate thioglycosides in combination with trifluoromethanesulfonic anhydride, which is attributed to its greater steric bulk. [ABSTRACT FROM AUTHOR]

Relative densities of NaCF3SO3(aq) at molalities 0.073 ≤ m/(mol-kg-1) ≤ 1.68 were measured with vibrating-tube densimeters from 283 K to 600 K and from 0.1 MPa to 20 MPa. Relative densities of HCF3SO3(aq) at molalities 0.12 < m/(mol-kg-1) < 2.1 were determined at temperatures from 283 K to 328 K at 0.1 MPa. Apparent molar volumes calculated from the measured densities were represented by the Pitzer ion-interaction treatment. The temperature and pressure dependence of the standard partial molar volume and the second virial coefficients in the Pitzer equation were expressed by empirical expressions in which the compression coefficient of water and temperature were used as independent variables. The conventional standard partial molar volumes V‡(CF3SO, aq) from T = 283 K to 573 K were calculated from the experimental values for V‡(NaCF3SO3, aq) and known values for V‡(Na+, aq). The values of V‡(CF3SO3/-, aq) at temperatures from 283 K to 328 K obtained from the values of V‡(NaCF3SO3, aq) and V‡(HCF3SO3, aq) agree to within 1.2 cm3-mol-1. [ABSTRACT FROM AUTHOR]

A scalable homogeneous metal‐catalyzed protocol for direct amidation of carboxylic acids is presented. The use of 2–10 mol% of the commercially available Zr(Cp)2(OTf)2·THF results in high yields of amides at moderate temperature, using an operationally convenient reaction protocol that circumvents the use of water scavenging techniques. [ABSTRACT FROM AUTHOR]