A systematic molecular dynamics study using large simulation boxes has been performed in order to extend the analysis of the mesoscopic segregation behavior observed in ionic liquids of the 1,3-dialkyl-imidazolium bis(trifluoromethylsulfonyl)imide homologous series, [C(n)C(mim)][Ntf2] (2 ≤ n ≤ 10, 2 ≤ m ≤ n). The analyses include the discussion of the structure factors, S(q), in the low-q range (1.6 ≤ q/nm(-1) ≤ 20); the confirmation of the periodicity of the polar network of the ionic liquid and its relation to the so-called intermediate peaks; and the characterization of the polar network and the nonpolar regions that are formed along the series using aggregate analyses by means of five different statistical tools. The analyses confirmed that the percolation of the nonpolar regions into a continuous domain occurs when the total number of carbon atoms in the alkyl chains exceeds six but that this is not a sufficient condition for the emergence of a distinct and intense prepeak. The existence of such a peak also requires that the longer alkyl chain contains more than a critical alkyl length (CAL) of five carbon atoms.

Due to the close relation between oxidative stress and a plethora of inflammatory diseases, antioxidants have received an increased attention for incorporation into dermatological products. Their use and absorption is however limited by their low solubility in water-rich formulations. Herein, a set of novel cholinium-based salts, namely dicholinium ellagate and cholinium caffeate, syringate, vanillate, gallate and salicylate were synthetized and characterized. Their melting and decomposition temperatures, water solubility, and toxicological, antioxidant, cytotoxicity and pro-/ anti-inflammatory activities were addressed. These new salts, exclusively composed of ions derived from natural sources, display a high thermal stability -up to 150 ºC. The synthesized compounds are significantly more soluble in water (in average, 3 orders of magnitude higher) than the corresponding phenolic acids. Furthermore, they present not only similar but even higher antioxidant and anti-inflammatory activities, as well as comparable cytotoxicity and lower ecotoxicity profiles than their acidic precursors. Amongst all the investigated salts, dicholinium ellagate is the most promising synthesized salt when considering the respective antioxidant and anti-inflammatory activities. Since all the synthesized salts are based on the cholinium cation, they can further be envisaged as essential nutrients to be used in oral drugs.

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The standard (p degrees = 0.1 MPa) molar enthalpies of formation of 2-, 3-, and 4-chloroaniline were derived from the standard molar energies of combustion, in oxygen, at T = 298.15 K, measured by rotating bomb combustion calorimetry. The Calvet high-temperature vacuum sublimation technique was used to measure the enthalpies of vaporization or sublimation of the three isomers. These two thermodynamic parameters yielded the standard molar enthalpies of formation of the three isomers of chloroaniline, in the gaseous phase, at T = 298.15 K, as 53.4 +/- 3.1 kJ.mol(-1) for 2-chloroaniline, 53.0 +/- 2.8 kJ.mol(-1) for 3-chloroaniline, and 59.7 +/- 2.3 kJ.mol(-1) for 4-chloroaniline. These values, which correct previously published data, were used to test the computational methodologies used. Therewith, gas-phase acidities, proton affinities, electron donor capacities, and N-H bond dissociation enthalpies were calculated and found to compare well with available experimental data for these parameters.

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The standard (p ¼ 0:1 MPa) molar enthalpies of formation of 2-, 3-, and 4-bromoaniline, 2,4-, 2,5-, and 2,6-dibromoaniline, and 2,4,6-tribromoaniline were derived from the standard molar enthalpies of combustion, in oxygen, which yields CO 2 (g), N 2 (g), and HBr Á 600H 2 O(l), at T ¼ 298:15 K, measured by using rotating-bomb calorimetry.The standard molar enthalpies of sublimation, or vaporization, of these compounds at T ¼ 298:15 K were measured by using Calvet microcalorimetry, and so their standard molar enthalpies of formation in the gaseous state were derived. The enthalpies of fusion of the solid compounds were determined by DSC. The gas-phase enthalpies of formation were also estimated by density functional theory calculations performed at the BP86/6-31+G Ã level. As a result it is confirmed that thermodynamic data is consistent with intramolecular N-HÁÁÁBr hydrogen bonding.Aromatic amines are of great importance in biological and material sciences as well as in pharmaceutical and chemical industries. Halogenated anilines have gained the most focus of all of the aromatic amines, due to their high toxicity and wide uses. For example, they may be used as reagents or precursors for synthesizing organic dyes, in pigments, in agricultural agents, in pharmaceuticals and in the rubber industries.1,2 Haloanilines are frequently found in both effluents of waste water treatment plants and surface water, due to chemical degradation or biotransformation of pesticides and herbicides, or due to accidental spills and illegal release of industrial and municipal wastewater. 3 These compounds have been determined to induce several kinds of toxicity, like methemoglobinemia, splenotoxicity, hepatotoxicity, and nephrotoxicity. 2,4Because of their stability in the presence of air and humidity, and potentially attractive economics, 5,6 aniline and haloanilines have been also used in the synthesis of conducting polymers with applications in rechargeable batteries, electromagnetic interference shielding, electrochromic display devices, sensors, and electrocatalysis.The current work presents the results of calorimetric and computational thermochemistry studies on bromoanilines. The experimental investigation includes the determination of the standard massic energies of combustion in oxygen at T ¼ 298:15 K of the different bromoanilines using a rotatingbomb combustion calorimeter, from which the values of the standard molar enthalpies of formation in the condensed phase were derived. The determination of the standard molar enthalpies of sublimation or vaporization at T ¼ 298:15 K was done by using Calvet microcalorimetry with the high-temperature vacuum sublimation technique; these values allowed the derivation of the standard molar enthalpies of formation, in the gaseous state, of 2-, 3-, and 4-bromoaniline, 2,4-, 2,5-, and 2,6-dibromoaniline, and 2,4,6-tribromoaniline, which were compared with values estimated by the Cox scheme 7 and those obtained by density functional theory calculations. Experimental Materials.The three mono...

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