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Organic Salts (organic + salt)
Selected AbstractsInorganic/Organic Salts as Heterogeneous Basic Catalysts for Cyanosilylation of Carbonyl Compounds.CHEMINFORM, Issue 52 2004Bin He Abstract For Abstract see ChemInform Abstract in Full Text. [source] A One-Pot Synthesis and Self-Assembled Superstructure of Organic Salts of a 1,5-Benzodiazepine Derivative.CHEMINFORM, Issue 33 2006Harjyoti Thakuria Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A Tunable Solid-State Fluorescence System Consisting of Organic Salts of Anthracene-2,6-disulfonic Acid with Primary Amines.CHEMINFORM, Issue 33 2005Yuji Mizobe Abstract For Abstract see ChemInform Abstract in Full Text. [source] Systematic Investigation of Molecular Arrangements and Solid-State Fluorescence Properties on Salts of Anthracene-2,6-disulfonic Acid with Aliphatic Primary AminesCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2009Yuji Mizobe Dr. Abstract Organic salts of anthracene-2,6-disulfonic acid (ADS) with a wide variety of primary amines have been fabricated, and their arrangements of anthracene molecules and solid-state fluorescence properties investigated. Single-crystal X-ray studies reveal that the salts show seven types of crystal forms and corresponding molecular arrangements of anthracene moieties depending on the amine, while anthracene shows only one form and arrangement in the solid state. Depending on the molecular arrangements, the ADS salts exhibit various solid-state fluorescence properties: spectral shift (30,nm) and suppression and enhancement of the fluorescence intensity. Especially the ADS salt with n -heptylamine (nHepA), which shows discrete anthracene moieties in the crystal, exhibits the highest quantum yield (,F=46.1±0.2,%) in the series of ADS salts, which exceeds that of anthracene crystal (,F=42.9±0.2,%). From these systematic investigations on the arrangements and the solid-state properties, the following factors are essential for high fluorescence quantum yield in the solid state: prevention of contact between , planes of anthracene moieties and immobilization of anthracene rings. In addition, such organic salts have potential as a system for modulating the molecular arrangements of fluorophores and the concomitant solid-state properties. Thus, systematic investigation of this system constructs a library of arrangements and properties, and the library leads to remarkable strategies for the development of organic solid materials. [source] A two-dimensional network in the molecular salt 2-methylimidazolium hydrogen glutarate, and three-dimensional networks in the salts 2-methylimidazolium hydrogen succinate and 2-methylimidazolium hydrogen adipate monohydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2009Xiang-Gao Meng All three title compounds, C4H7N2+·C4H5O4,, (I), C4H7N2+·C5H7O4,, (II), and C4H7N2+·C6H9O4,·H2O, (III), can be regarded as 1:1 organic salts. The dicarboxylic acids join through short acid bridges into infinite chains. Compound (I) crystallizes in the noncentrosymmetric Cmc21 space group and the asymmetric unit consists of a hydrogen succinate anion located on a mirror plane and a 2-methylimidazolium cation disordered across the same mirror. The other two compounds crystallize in the triclinic P space group. The carboxylic acid H atom in (II) is disordered over both ends of the anion and sits on inversion centres between adjacent anions, forming symmetric short O...H...O bridges. Two independent anions in (III) sit across inversion centres, again with the carboxylic acid H atom disordered in short O...H...O bridges. The molecules in all three compounds are linked into two-dimensional networks by combinations of imidazolium,carboxylate N+,H...O and carboxylate,carboxylate O,H...O hydrogen bonds. The two-dimensional networks are further linked into three-dimensional networks by C,H...O hydrogen bonds in (I) and by Owater,H...O hydrogen bonds in (III). According to the ,pKa rule, such 1:1 types of organic salts can be expected unambiguously. However, a 2:1 type of organic salt may be more easily obtained in (II) and (III) than in (I). [source] Two polymorphs of morpholin-4-ium 2-(5-methyl-1H -1,2,4-triazol-3-ylsulfanyl)acetateACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2009Svetlana V. Shishkina Two polymorphs of the title organic salt (a very effective medicinal preparation with the commercial name thiotriazoline), C4H10NO+·C5H6N3O2S,, were obtained. The cations and anions are connected by hydrogen bonds and extend into two-dimensional networks. The main packing motifs are an R44(12) cluster in the monoclinic form and a chain in the orthorhombic form. [source] Flux enhancement in TFC RO membranesENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2001Mark A. Kuehne The effects of varying processing conditions during fabrication of TFC RO membranes were systematically investigated. It was found that the membrane flux is greatly dependent on the processing steps that follow the synthesis of the thin film coating, such as washing, treatment with glycerol, and drying of the membrane. Glycerol is not simply a passive flux - p reserving agent, preventing loss of porosity during oven drying. In combination with a second oven drying step, glycerol actively enhances flux. Membrane flux can be similarly enhanced by treatment with solutions of organic salts, followed by oven drying. The effect of these treatments is quite large, increasing the flux by 30,70%, with no loss of salt rejection. Flux-enhancing additives were also used in the aqueous polyamine solution used to prepare the thin film coating. [source] Direct and indirect effects of a potential aquatic contaminant on grazer,algae interactionsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2009Michelle A. Evans-White Abstract Contaminants have direct, harmful effects across multiple ecological scales, including the individual, the community, and the ecosystem levels. Less, however, is known about how indirect effects of contaminants on consumer physiology or behavior might alter community interactions or ecosystem processes. We examined whether a potential aquatic contaminant, an ionic liquid, can indirectly alter benthic algal biomass and primary production through direct effects on herbivorous snails. Ionic liquids are nonvolatile organic salts being considered as an environmentally friendly potential replacement for volatile organic compounds in industry. In two greenhouse experiments, we factorially crossed four concentrations of 1-N-butyl-3-methylimidazolium bromide (bmimBr; experiment 1: 0 or 10 mg/L; experiment 2: 0, 1, or 100 mg/L) with the presence or absence of the snail Physa acuta in aquatic mesocosms. Experimental results were weighted by their respective control (no bmimBr or P. acuta) and combined for statistical analysis. When both bmimBr and snails were present, chlorophyll a abundance and algal biovolume were higher than would be expected if both factors acted additively. In addition, snail growth rates, relative to those of controls, declined by 41 to 101% at 10 and 100 mg/L of bmimBr. Taken together, these two results suggest that snails were less efficient grazers in the presence of bmimBr, resulting in release of algae from the grazer control. Snails stimulated periphyton primary production in the absence, but not in the presence, of bmimBr, suggesting that bmimBr also can indirectly alter ecosystem function. These findings suggest that sublethal contaminant levels can negatively impact communities and ecosystem processes via complex interactions, and they provide baseline information regarding the potential effects of an emergent industrial chemical on aquatic systems. [source] Thermodynamic modeling of hydrotrope solutionsAICHE JOURNAL, Issue 1 2006Mandana Akia Abstract A new model for the excess Gibbs energy of hydrotrope solutions is presented. This model is based on the local composition model by Chen et al. Hydrotropes are usually organic salts that can increase the solubility of organic and inorganic compounds in water. The proposed model has five adjustable parameters; one of them is related to long-range forces, and four of them are related to short-range forces. Long-range forces are modeled by the Pitzer-Debye-Huckel equation. However, in our model, the effect of the molecular solute on the dielectric constant of water has also been considered. Modeling of short-range forces is based on local composition concepts. The model parameters are obtained using experimental data for six hydrotropes with four solutes at different temperatures. The water solubility of molecular solutes in the presence of hydrotropes has been calculated for different systems. Accurate results are obtained. © 2005 American Institute of Chemical Engineers AIChE J, 2006 [source] Ionic liquids in the synthesis and modification of polymersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2005Przemys, aw Kubisa Abstract Ionic liquids are organic salts that are liquid at ambient temperatures, preferably at room temperature. They are nonvolatile, thermally and chemically stable, highly polar liquids that dissolve many organic, inorganic, and metallo-organic compounds. Many combinations of organic cations with different counterions are already known, and the properties of ionic liquids may be adjusted by the proper selection of the cation and counterion. In the last decade, there has been increasing interest in using ionic liquids as solvents for chemical reactions. The interest is stimulated not only by their nonvolatility (green solvents) but also by their special properties, which often affect the course of a reaction. In recent years, ionic liquids have also attracted the attention of polymer chemists. Although the research on using ionic liquids in polymer systems is still in its infancy, several interesting possibilities have already emerged. Ionic liquids are used as solvents for polymerization processes, and in several systems they indeed show some advantages. In radical polymerization, the kp/kt ratio (where kp is the rate constant of propagation and kt is the rate constant of termination) is higher than in organic media, and thus better control of the process can be achieved. Ionic liquids, as electrolytes, have also attracted the attention of researchers in the fields of electrochemical polymerization and the synthesis of conducting polymers. Finally, the blending of ionic liquids with polymers may lead to the development of new materials (ionic liquids may act as plasticizers, electrolytes dispersed in polymer matrices, or even porogens). In this article, the new developments in these fields are briefly discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4675,4683, 2005 [source] The lines-of-force landscape of interactions between molecules in crystals; cohesive versus tolerant and `collateral damage' contactACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2010Angelo Gavezzotti A quantitative analysis of relative stabilities in organic crystal structures is possible by means of reliable calculations of interaction energies between pairs of molecules. Such calculations have been performed by the PIXEL method for 1108 non-ionic and 98 ionic organic crystals, yielding total energies and separate Coulombic polarization and dispersive contributions. A classification of molecule,molecule interactions emerges based on pair energy and its first derivative, the interaction force, which is estimated here explicitly along an approximate stretching path. When molecular separation is not at the minimum-energy value, as frequently happens, forces may be attractive or repulsive. This information provides a fine structural fingerprint and may be relevant to the mechanical properties of materials. The calculations show that the first coordination shell includes destabilizing contacts in ,,9% of crystal structures for compounds with highly polar chemical groups (e.g. CN, NO2, SO2). Calculations also show many pair contacts with weakly stabilizing (neutral) energies; such fine modulation is presumably what makes crystal structure prediction so difficult. Ionic organic salts or zwitterions, including small peptides, show a Madelung-mode pairing of opposite ions where the total lattice energy is stabilized from sums of strongly repulsive and strongly attractive interactions. No obvious relationships between atom,atom distances and interaction energies emerge, so analyses of crystal packing in terms of geometrical parameters alone should be conducted with due care. [source] Two-dimensional networks in 2-methylanilinium picrate and 2,5-dichloroanilinium picrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Gao-Xiang Meng Both the title molecular adducts of 2-methylaniline or 2,5-dichloroaniline with picric acid are 1:1 organic salts, namely 2-methylanilinium picrate, C7H10N+·C6H2N3O7,, (I), and 2,5-dichloroanilinium picrate, C6H6Cl2N+·C6H2N3O7,, (II). In both structures, the phenoxide O atoms accept two N,H hydrogen bonds in a bifurcated acceptor fashion, which link the component ions by N,H...O hydrogen bonds into continuous two-dimensional zigzag layers, running parallel to the (100) plane in (I) and the (010) plane in (II). A ,,, interaction is observed between symmetry-related anilinium cations in (I), while in (II), Cl...Onitro and Cl...Cl interactions are observed. This study indicates that a substitution on aniline can exert a pivotal influence on the construction of its supramolecular structure. [source] Supramolecular association in proton-transfer adducts containing benzamidinium cations.ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2010Four organic salts, namely benzamidinidium orotate (2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylate) hemihydrate, C7H9N2+·C5H3N2O4,·0.5H2O (BenzamH+·Or,), (I), benzamidinium isoorotate (2,4-dioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate) trihydrate, C7H9N2+·C5H3N2O4,·3H2O (BenzamH+·Isor,), (II), benzamidinium diliturate (5-nitro-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate) dihydrate, C7H9N2+·C4H2N3O5,·2H2O (BenzamH+·Dil,), (III), and benzamidinium 5-nitrouracilate (5-nitro-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-ide), C7H9N2+·C4H2N3O4, (BenzamH+·Nit,), (IV), have been synthesized by a reaction between benzamidine (benzenecarboximidamide or Benzam) and the appropriate carboxylic acid. Proton transfer occurs to the benzamidine imino N atom. In all four acid,base adducts, the asymmetric unit consists of one tautomeric aminooxo anion (Or,, Isor,, Dil, and Nit,) and one monoprotonated benzamidinium cation (BenzamH+), plus one-half (which lies across a twofold axis), three and two solvent water molecules in (I), (II) and (III), respectively. Due to the presence of protonated benzamidine, these acid,base complexes form supramolecular synthons characterized by N+,H...O, and N+,H...N, (±)-charge-assisted hydrogen bonds (CAHB). [source] Hydrogen-bond-directed supramolecular arrays in 4,4,-bipyridinium tetrachloroterephthalate dihydrate and bis(1,10-phenanthrolinium) tetrachloroterephthalate tetrachloroterephthalic acid trihydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Ming-Yang He The title compounds, C10H10N22+·C8Cl4O42,·2H2O, (I), and 2C12H9N2+·C8Cl4O42,·C8H2Cl4O4·3H2O, (II), both crystallize as charge-transfer organic salts with the dianionic or neutral acid components lying on inversion centres. The acid and base subunits in (I) arrange alternately to generate a linear tape motif via N,H...O hydrogen bonds; these tapes are further combined into a three-dimensional architecture through multiple O,H...O and C,H...O interactions involving solvent water molecules. In contrast, the neutral and anionic acid components in (II) are linked to form a zigzag chain by means of O,H...O hydrogen bonds between acid groups, with dangling 1,10-phenanthrolinium units connected to these chains by carboxylate,pyridinium interactions with R22(7) hydrogen-bond notation. Adjacent chains are further extended to result in a two-dimensional corrugated layer network via,,, interactions. Inter-ion Cl...O interactions are also found in both (I) and (II). [source] Three-dimensional networks in bis(imidazolium) 2,2,-dithiodibenzoate and 4-methylimidazolium 2-[(2-carboxyphenyl)disulfanyl]benzoateACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2009Linheng Wei Cocrystallization of imidazole or 4-methylimidazole with 2,2,-dithiodibenzoic acid from methanol solution yields the title 2:1 and 1:1 organic salts, 2C3H5N2+·C14H10O4S22,, (I), and C4H7N2+·C14H10O4S2,, (II), respectively. Compound (I) crystallizes in the monoclinic C2/c space group with the mid-point of the S,S bond lying on a twofold axis. The component ions in (I) are linked by intermolecular N,H...O hydrogen bonds to form a two-dimensional network, which is further linked by C,H...O hydrogen bonds into a three-dimensional network. In contrast, by means of N,H...O, N,H...S and O,H...O hydrogen bonds, the component ions in (II) are linked into a tape and adjacent tapes are further linked by ,,,, C,H...O and C,H..., interactions, resulting in a three-dimensional network. [source] A two-dimensional network in the molecular salt 2-methylimidazolium hydrogen glutarate, and three-dimensional networks in the salts 2-methylimidazolium hydrogen succinate and 2-methylimidazolium hydrogen adipate monohydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2009Xiang-Gao Meng All three title compounds, C4H7N2+·C4H5O4,, (I), C4H7N2+·C5H7O4,, (II), and C4H7N2+·C6H9O4,·H2O, (III), can be regarded as 1:1 organic salts. The dicarboxylic acids join through short acid bridges into infinite chains. Compound (I) crystallizes in the noncentrosymmetric Cmc21 space group and the asymmetric unit consists of a hydrogen succinate anion located on a mirror plane and a 2-methylimidazolium cation disordered across the same mirror. The other two compounds crystallize in the triclinic P space group. The carboxylic acid H atom in (II) is disordered over both ends of the anion and sits on inversion centres between adjacent anions, forming symmetric short O...H...O bridges. Two independent anions in (III) sit across inversion centres, again with the carboxylic acid H atom disordered in short O...H...O bridges. The molecules in all three compounds are linked into two-dimensional networks by combinations of imidazolium,carboxylate N+,H...O and carboxylate,carboxylate O,H...O hydrogen bonds. The two-dimensional networks are further linked into three-dimensional networks by C,H...O hydrogen bonds in (I) and by Owater,H...O hydrogen bonds in (III). According to the ,pKa rule, such 1:1 types of organic salts can be expected unambiguously. However, a 2:1 type of organic salt may be more easily obtained in (II) and (III) than in (I). [source] Three-dimensional networks in the 1:2 organic salts 2,2,-biimidazolium bis(3-carboxy-4-hydroxybenzenesulfonate) and 2,2,-bibenzimidazolium bis(3-carboxy-4-hydroxybenzenesulfonate) trihydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009Chun-Shan Zhou The two title compounds of 2,2,-biimidazole (Bim) with 5-sulfosalicylic acid (5-H2SSA) and 2,2,-bibenzimidazole (Bbim) with 5-H2SSA are 1:2 organic salts, viz. C6H8N42+·2C7H5O6S,, (I), and C14H12N42+·2C7H5O6S,·3H2O, (II). The cation of compound (I) lies on a centre of inversion, whereas that of (II) lies on a twofold axis. Whilst compound (I) is anhydrous, three water molecules are incorporated into the crystal structure of (II). The substitution of imidazole H atoms by other chemical groups may favour the incorporation of water molecules into the crystal structure. In both compounds, the component cations and anions adopt a homogeneous arrangement, forming alternating cation and anion layers which run parallel to the (001) plane in (I) and to the (100) plane in (II). By a combination of N,H...O, O,H...O and C,H...O hydrogen bonds, the ions in both compounds are linked into three-dimensional networks. In addition, ,,, interactions are observed between symmetry-related benzene rings of Bbim2+ cations in (II). [source] Two three-dimensional networks in the binary molecular adducts 4-methylimidazolium hydrogen terephthalate and bis(4-methylimidazolium) terephthalateACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2008Xiang-Gao Meng Both the 1:1 and 2:1,molecular adducts of 4-methylimidazole (4-MeIm) and terephthalic acid (H2TPA) are organic salts, viz. C4H7N2+·C8H5O4,, (I), and 2C4H7N2+·C8H4O42,, (II), respectively. The component ions in (I) are linked by N,H...O and O,H...O hydrogen bonds into continuous two-dimensional layers built from R64(32) hydrogen-bond motifs running parallel to the (100) plane. These adjacent two-dimensional layers are in turn linked by a combination of C,H...O, C,H..., and ,,, interactions into a three-dimensional network. In the crystal structure of (II), with the anion located on an inversion centre, only N,H...O hydrogen bonds result in two-dimensional layers built from R88(42) hydrogen-bond motifs running parallel to the (102) plane. Being similar to those in (I), these layers are also linked by means of C,H...O, C,H..., and ,,, interactions, forming a three-dimensional network. This study indicates that, on occasion, a change of the reactant concentration can exert a pivotal influence on the construction of supramolecular structures based on hydrogen bonds. [source] Cryoprotection properties of salts of organic acids: a case study for a tetragonal crystal of HEW lysozymeACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2010Grzegorz Bujacz Currently, the great majority of the data that are used for solving macromolecular structures by X-ray crystallography are collected at cryogenic temperatures. Selection of a suitable cryoprotectant, which ensures crystal stability at low temperatures, is critical for the success of a particular diffraction experiment. The effectiveness of salts of organic acids as potential cryoprotective agents is presented in the following work. Sodium formate, acetate, malonate and citrate were tested, as were sodium potassium tartrate and acetate in the form of potassium and ammonium salts. For each salt investigated, the minimal concentration that was required for successful cryoprotection was determined over the pH range 4.5,9.5. The cryoprotective ability of these organic salts depends upon the number of carboxylic groups; the lowest concentration required for cryoprotection was observed at neutral pH. Case-study experiments conducted using the tetragonal form of hen egg-white lysozyme (HEWL) confirmed that salts of organic acids can successfully act as cryoprotective agents of protein crystals grown from high concentrations of inorganic salts. When crystals are grown from solutions containing a sufficient concentration of organic acid salts no additional cryoprotection is needed as the crystals can safely be frozen directly from the crystallizing buffers. [source] Systematic Investigation of Molecular Arrangements and Solid-State Fluorescence Properties on Salts of Anthracene-2,6-disulfonic Acid with Aliphatic Primary AminesCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2009Yuji Mizobe Dr. Abstract Organic salts of anthracene-2,6-disulfonic acid (ADS) with a wide variety of primary amines have been fabricated, and their arrangements of anthracene molecules and solid-state fluorescence properties investigated. Single-crystal X-ray studies reveal that the salts show seven types of crystal forms and corresponding molecular arrangements of anthracene moieties depending on the amine, while anthracene shows only one form and arrangement in the solid state. Depending on the molecular arrangements, the ADS salts exhibit various solid-state fluorescence properties: spectral shift (30,nm) and suppression and enhancement of the fluorescence intensity. Especially the ADS salt with n -heptylamine (nHepA), which shows discrete anthracene moieties in the crystal, exhibits the highest quantum yield (,F=46.1±0.2,%) in the series of ADS salts, which exceeds that of anthracene crystal (,F=42.9±0.2,%). From these systematic investigations on the arrangements and the solid-state properties, the following factors are essential for high fluorescence quantum yield in the solid state: prevention of contact between , planes of anthracene moieties and immobilization of anthracene rings. In addition, such organic salts have potential as a system for modulating the molecular arrangements of fluorophores and the concomitant solid-state properties. Thus, systematic investigation of this system constructs a library of arrangements and properties, and the library leads to remarkable strategies for the development of organic solid materials. [source] | |||||||||||||