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The preparation of substituted quinoline derivatives through a Friedlander condensation reaction utilizing the ionic liquid [bmim][B[F.sub.4]] as the reaction medium and iron chloride hexahydrate (Fe[Cl.sub.3] x 6[H.sub.2]O) as a catalyst is described. The advantages in using this method include its environmental friendliness, simple operating process in both mild and neutral reaction conditions, and good yields. Key words: ionic liquid, Friedlander reaction, quinoline derivatives, green chemistry. On decrit l'utilisation du [bmim][B[F.sub.4]], un liquide ionique, comme milieu reactionnel et de l'hexahydrate du chlorure de fer (Fe[Cl.sub.3]x6[H.sub.2]O) comme catalyseur pour la preparation de derives de quinoleines substituees par la reaction de condensation de Friedlander. Cette methode presente l'avantage d'etre benigne pour l'environnement, d'impliquer un processus d'operation simple, de se faire dans des conditions douces et neutres et de donner de bons rendements. Mots cles : liquide ionique, reaction de Friedlander, derives de la quinoleine, chimie verte. [Traduit par la Redaction]

Apparent molar volumes [V.sub.2,[phi]] and standard partial molar volumes [V.sup.[omicron].sub.2,[phi]] for tetraethylammonium bromide ([Et.sub.4]NBr), tetrapropylammonium bromide ([Pr.sub.4]NBr), tetrabutylammonium bromide ([Bu.sub.4]NBr), and tetrahexylammonium bromide ([Hex.sub.4]NBr) have been determined at 298.15 K from precise density measurements in solvent mixtures of propylene carbonate (PC) with N,N-dimethylformamide (DMF). Combined with our previous data for LiCl[O.sub.4] and LiBr in the same solvents, ionic molar volumes of [Li.sup.+], [Et.sub.4][N.sup.+], [Pr.sub.4][N.sup.+], [Bu.sub.4][N.sup.+], [Hex.sub.4][N.sup.+], and related anions have been deduced from the extrapolation method suggested by Conway and co-workers. It is shown that the molar volumes of these cations are quite independent of the nature of the solvent and the composition of the solvent mixtures, in contrast to those of CI[O.sub.4.sup.-] and [Br.sup.-] anions. This suggests that the Lewis-base-type solvents with similar molecular volumes have similar interactions with [Li.sup.+]. The constancy in partial molar volume for tetraalkylammonium ions provides helpful evidence for the lack of solvation of large tetraalkylammonium cations in organic solvents. These findings have been interpreted using scaled-particle theory. The results are discussed in terms of ion solvation, packing effects of solvent molecules in the solvation shell, and the electrostriction of solvents. Key words: ionic volumes, propylene carbonate, N,N-dimethylformamide, solvent mixtures, solvation, lithium batteries.

Apparent molar volumes ([V.sub.2,[PHI]]) and standard partial-molar volumes ([V.sup.0.sub.2,[PHI]]) of LiCl[O.sub.4] and LiBr at 298.15 K have been determined from precise density measurements in solvent mixtures of propylene carbonate (PC) with dimethylformamide (DMF), tetrahydrofuran (THF), acetonitrile (AN), and methyl formate (MF). The scaled particle theory is used to calculate the contributions of the cavity formation and the electrolyte-solvent interactions to the standard partial-molar volumes. It is shown that [V.sup.0.sub.2,[PHI]] is strongly dependent on the nature of the solvents, and the trends in [V.sup.0.sub.2,[PHI]] with composition of the solvent mixtures are determined by the interaction volumes of electrolytes with solvents. The results are discussed in terms of ionic preferential solvation, packing effect of solvents in the solvation shell, and electrostriction of solvents by ion. Key words: partial-molar volume, scaled particle theory, lithium salts, propylene carbonate, solvent mixtures, lithium battery electrolytes.

Fluorescent single crystals that respond to multiple external stimuli are of great interest in molecular machines, sensors, and displays. The integration of photo‐ or acid‐induced fluorescence enhancement and bending in one organic crystal, however, has not been reported yet. Herein, we report the interesting plastic photomechanical bending and switching on of the fluorescence of an azine crystal in a single‐crystal transformation, due to extended π‐conjugation and molecular slippage. Moreover, the fluorescent plastic bending driven by multiple volatile acid vapors was firstly observed, and attributed to the synergistic effect of push–pull electronic structure and hydrogen bonding. The single crystal also shows high elasticity under external force. In addition, reversible fluorescence switching can be triggered by grinding and solvent fuming, as well as by the adsorption and desorption of HCl vapor. The integration of plastic, elastic bending and switch‐on fluorescence into one single crystal provides a new strategy for next‐generation smart materials. [ABSTRACT FROM AUTHOR]

The syntheses of the marine metabolites verongamine, hemibastadin-2 and aerothionin were developed using the cyano ylide coupling methodology. The technique involved the transformation of a carboxylic acid to an acyl cyano phosphorane that can be oxidized to an alpha,beta-diketo nitrile. The conversion of the strongly electrophilic intermediate to alpha-keto amides was easily performed by amines.

A study was conducted to analyze thermodynamics associated with the interaction of HCl with D-fructose in water at 278.15-318.15 K. D-Fructose was dried under vacuum at 343 K to constant weight before being stored in a desiccator. The values of enthalpic group parameters were determined from various subsets of data. In addition, differences in the interaction of HCl between D-fructose and D-glucose were examined based on H+-induced structural changes.