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A series of task-specific ionic liquids (TSILs) based on glycerylimidazolium cations have been prepared by reaction of 1-chloropropanediol, a compound obtainable from glycerol (a widely available and in-expensive waste product), with the appropriate base (1-H-imidazole, 1,2-dimethylimidazole and 1-methyl-1-H-imidazole). The reaction of 3-(1H-imidazol-1-yl)propane-1,2-diol with chloroalkanes, bromoalkanes and alkyl mesylates gave the corresponding salts which were characterized. The possibility to use these ILs in palladium catalyzed reactions was evaluated, evidencing good catalyst stability and a high recyclability. [ABSTRACT FROM AUTHOR]

A new rapid synthesis of γ-lactones, cis fused with a cyclopentenic ring by thermal of 7-chloro-2-(methoxycarbonyl)-4-6-dimethylocta-7-phenyl (or methyl) (2 E,4 E,6 E)-trienoic acids was reported. The key step implicates an to a cyclopentenyl cation, according to an electrocyclic π2s + π2a conrotatory process, published in a recent paper (from the corresponding diacids). We have investigated the thermal behavior of the corresponding half-esters since; if the obeys to the proposed mechanism, the diacids, half-esters must also cyclize in a similar manner. of these led to γ-dilactones via intermediary cyclopropanes. Mechanistic pathways were investigated. [ABSTRACT FROM AUTHOR]

The paper describes an asymmetric approach to the synthesis of the (2S,4S,6S)-2,4,6-trimethylnonyl segment of siphonarienes. The key step used is a newly developed methodology to obtain sec-dialkyl acetylenes based on the intramolecular hydride transfer from a secondary g-benzyloxy group with well-defined absolute stereochemistry, ensured by a Sharpless asymmetric epoxidation reaction, to a cation generated by Lewis acid treatment of a tertiary Co 2 (CO) 6 -complexed propargylic alcohol. [ABSTRACT FROM AUTHOR]

A 3D inorganic-organic hybrid proton conductor, [Sm(H2O)5(CO2CH2NH3)2][Al(OH)6Mo6O18]·10H2O (1), has been synthesized by using coordination cations, [Sm(H2O)5(gly)2]3+ (gly = -CO2CH2NH3 +), and polyanions, [Al(OH)6Mo6O18]3- ([AlMo6]) and the coordination cations ([Sm(H6]) and the coordination cations ([Sm(H2O)5(gly)2]3+) stack to form a 3D supramolecular network structure containing 1D channels along the c axis by electrostatic force and H-bonding. Significantly, the 1D channels are water-filled with a high water content (both Sm coordinated and in lattice). Dynamic adsorption measurements were implemented at 1 atm, and 95% relative humidity (RH). The water adsorption amount (6.51 wt% at 25 °C and 5.68 wt% at 80 °C) consistent with the number of lattice water molecules of 1 suggests that the water chains were retained at elevated temperatures (80 °C) under 95% RH. Alternating-current (AC) impedance measurements of 1 reveal an outstanding conductivity for 1 of 4.53 × 10-3 S cm-1 at 80 °C under 95% RH. The activation energy of 1 calculated from the Arrhenius plots of the proton conductivity is 1.09 eV, which indicated that the protons transfer by a vehicle mechanism. [ABSTRACT FROM AUTHOR]

A series of amphiphilic N-(2-hydroxy)propyl-3-trimethylammonium-chitosan-cholic acid (HPTA-CHI-CA) polymers were synthesized by grafting cholic acid (CA) and glycidyltrimethylammonium chloride onto chitosan. The self-assembly behavior of HPTA-CHI-CA was studied by fluorescence technique. The polymers were able to self-assemble into NPs in phosphate buffered saline with a critical aggregation concentration (CAC) in the range of 66–26 mg/L and the CAC decreased with the increasing of the degree of substitution (DS) of CA. The size of cationic HPTA-CHI-CA NPs ranges from 170 to 220 nm (PDI < 0.2). It was found that doxorubicin (DOX) could be encapsulated into HPTA-CHI-CA NPs based on self-assembly. The drug loading content and efficiency varies depending on the DS of CA and feeding ratio of DOX to polymer. In vitro release studies suggested that DOX released slowly from HPTA-CHI-CA NPs without any burst initial release. Besides, the confocal microscopic measurements indicated that DOX-HPTA-CHI-CA NPs could easily be uptaken by breast cancer (MCF-7) cells and release DOX in cytoplasm. Anti-tumor efficacy results showed that DOX-HPTA-CHI-CA NPs have a significant activity of inhibition MCF-7 cells growth. These results suggest cationic HPTA-CHI-CA may have great potential for anticancer drug delivery. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the ionic liquids 1,2-diethylpyridinium ethylsulfate, EEpyESO4; 1-methylpyridinium methylsulfate, MpyMSO4; 1,3-dimethylpyridinium methylsulfate, MMpyMSO4; and 2-ethyl-1-methylpyridinium methylsulfate, EMpyMSO4; were synthesized in our laboratory, and their experimental densities, speeds of sound, dynamic viscosities, and refractive indices were studied as a function of temperature at atmospheric pressure. Thermal expansion coefficient, molar volume, and molar refraction of these ionic liquids were calculated from the experimental density and refractive index values. [ABSTRACT FROM AUTHOR]

This paper describes a unique application of the fluoronium cation (F+) as an organocatalyst for mediating the reaction between N-substituted imines and ethyl diazoacetate affording excellent yields of N-substituted aziridines. [ABSTRACT FROM AUTHOR]

Abstract  The kinetics of the formation of cationic starch ethers under the action of 3-chloro-2-hydroxypropyltrimethylammonium chloride is studied in relation to the reactant molar ratio, temperature, and concentration of the starch suspension. Comparative data on how the content of the introduced catoinic groups depends on the origin of native starch are presented. The efficiency of starch cationization and the physicochemical properties of the synthesized samples are examined by chemical analysis, scanning electron microscopy, X-ray diffraction analysis, and thermal gravimetric analysis. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of α‐alkylidene cyclic carbonates (αCCs) by the carboxylative coupling of CO2 with propargylic alcohols is receiving increasing interest but requires the use of catalysts that are most often added in large quantities and/or lack selectivity. Herein, we describe the fine‐tuning of the structure of organocatalysts of the ammonium‐type that enables us to identify the important structural parameters that dictate their catalytic performance. Tetrabutylammonium oxalate was revealed to be one of the most attractive organocatalysts with a remarkably fast, complete and selective production of αCCs at a low catalyst loading (2.5 mol %) under solvent‐free conditions. This study opens new avenues for the facile and selective synthesis of libraries of αCCs from CO2 and propargylic alcohol by using simple organocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: Counterion‐induced stereocontrol is a powerful tool in organic synthesis. However, such enantiocontrol on tetrahedral ammonium cations remains challenging. Described here is the first example of using chiral anion phase‐transfer catalysis to achieve intermolecular ring‐opening of azetidiniums with excellent enantioselectivity (up to 97 % ee). Precise control over the formation and reaction of the chiral ion pair as well as inhibition of the background reaction by the biphasic system is key to the success of the reaction. [ABSTRACT FROM AUTHOR]

The substituted monomeric phosphanylboranes Ph2P−BH2 ⋅NMe3 ( 1) and tBuHP−BH2 ⋅NMe3 ( 2) have been used for the synthesis of cationic chain compounds built up by R2P−BH2 units. With a simple synthesis route, the highly stable cations [Me3N ⋅H2B−PR1R2−BH2 ⋅NMe3]+ ( 1 a, 2 a) and [Me3N ⋅H2B−PR1R2−BH2−PR1R2−BH2 ⋅NMe3]+ ( 1 b, 2 b) (R1=R2=Ph; R1=H, R2= tBu) are obtained as iodide (I−) salts. The reaction of H2As−BH2 ⋅NMe3 ( 3) with IBH2 ⋅SMe2 leads to [Me3N ⋅H2B−AsH2−BH2−AsH2−BH2 ⋅NMe3][I] ( 3 a), the longest so far known arsanylborane chain. Compound 3 a reacts with acetonitrile through a formal hydroarsination reaction to form [cyclo-{As(BH2 ⋅NMe3)(CMe=NH)2(BH2)}][I] ( 4). The reported synthetic strategy has proved to be a powerful tool for the formation of small, cationic oligomeric units. All products were comprehensively characterized by X-ray structure analysis, NMR, IR spectroscopy, and mass spectrometry in cooperation with DFT calculations. [ABSTRACT FROM AUTHOR]

Switchable reactivity through cationic gold-based catalyst control built on the oxidation state, namely cationic AuIII versus AuI, has been achieved in the direct functionalization of 2-azetidinone-tethered alkynyl indoles. [ABSTRACT FROM AUTHOR]

Rim-to-rim-connected phosphonate biscavitands 1a and 1b were synthesized. Crystal structure analysis and variable-temperature NMR spectroscopy studies reveal that 1a is more rigid in conformation than 1b. Biscavitands 1a and 1b bind cationic guests G1- G3 through hydrogen bonding and CH-π interactions, demonstrating positive and negative allosteric effects, respectively. The allosteric effects in guest binding are associated with the conformational flexibilities of 1a and 1b. The positive allosteric effect of 1a is directed by the tightly connected cavities, in which information of the first guest binding is transferred to the remaining cavity, which becomes preorganized. In contrast, a slightly negative allosteric effect is found in more-flexible 1b. [ABSTRACT FROM AUTHOR]

A novel zigzag chain organic–inorganic hybrid compound of the general formula R2MI5, [n-C3H7NH3]2[SbI5] (1), was successfully synthesized, in which the n-propylammonium cations were located in the free cavities between the one-dimensional zigzag chains. Systematic characterization was performed to investigate the phase transition of 1. A pair of sharp peaks at 211.8 K (heating) and 203.7 K (cooling) with a hysteresis 8.1 K were observed in the differential scanning calorimetry (DSC) curve, indicating the first-order phase transition behavior of 1. The temperature dependence dielectric measurement demonstrated a step-like change at around 211.8 K, which makes 1 a potential switchable dielectric material. Frequency dependence measurement revealed that the frequency exerts a weak influence on the dielectric permittivity. Further structural analysis shows that both anionic and cationic moieties contribute to the phase transition, accompanied by weak hydrogen bond interactions between cations and the [SbI5]n2− chains. [ABSTRACT FROM AUTHOR]

The bottom-up synthesis of organometallic zinc clusters is described. The cation {[Zn10](Cp*)6Me}+ ( 1) is obtained by reacting [Zn2Cp*2] with [FeCp2][BAr4F] in the presence of ZnMe2. In the presence of suitable ligands, the high reactivity of 1 enables the controlled abstraction of single Zn units, providing access to the lower-nuclearity clusters {[Zn9](Cp*)6} ( 2) and {[Zn8](Cp*)5(tBuNC)3}+ ( 3). According to DFT calculations, 1 and 2 can be described as closed-shell species that are electron-deficient in terms of the Wade-Mingos rules because the apical ZnCp* units that constitute the cluster cage do not have three, but only one, frontier orbitals available for cluster bonding. Zinc behaves flexibly in building the skeletal metal-metal bonds, sometimes providing one major frontier orbital (like Group 11 metals) and sometimes providing three frontier orbitals (like Group 13 elements). [ABSTRACT FROM AUTHOR]

The present review article highlights recent progress in the field of iron-catalyzed cross-coupling reactions between Csp centers. The reaction scope of various iron-catalyzed couplings between aromatic Grignard reagents and unsaturated halides is described and some mechanistic insights are given. 1 Introduction 2 Historical Work 3 Iron-Catalyzed Homocouplings of Aryl Organometallics 4 Iron-Catalyzed sp2-sp2 Cross-Couplings 4.1 Arylcopper Reagents as Nucleophiles 4.2 Arylmagnesium Reagents as Nucleophiles 4.2.1 Couplings with Alkenyl Halides 4.2.2 Couplings with Heteroaryl Halides 4.2.3 Coupling with Aryl Halides 5 Conclusion [ABSTRACT FROM AUTHOR]

Three new salts of tetrahedral rhenium chalcocyanide cluster anions [Re4Q4(CN)12]4−(Q = S, Se, Te) and 1,10-phenanthroline-1-ium cations, (phenH)4[Re4S4(CN)12]·6H2O (1), (phenH)4[Re4Se4(CN)12]·6H2O (2), and (phenH)4[Re4Te4(CN)12]·10H2O (3), have been synthesized by reactions of K4[Re4Q4(CN)12]·nH2O with 1,10-phenanthroline in the presence of Nd3+in an acidic aqueous medium (pH 4).1and2exhibit similar 2-D layered supramolecular architectures based on hydrogen bonds between water molecules, CN-groups of cluster anions, andphenH+cations. The latter are involved inπ–πand C–H⋯πstacking interactions, connecting the adjacent layers with each other. Complex3demonstrates a 3-D framework based on hydrogen bonds between water molecules and CN-groups,π–πand C–H⋯πinteractions. Notably short O···Te contacts of 3.40 and 3.50 Å are found in the structure of3. The thermal properties of1–3have been investigated by TG-DTG. [ABSTRACT FROM PUBLISHER]

Pyranosidic allylic (Ferrier) cations that share dicobalt hexacarbonyl propargyl (Nicholas) stabilization at C-1, can be easily generated by treatment of hexacarbonyldicobalt alkynyl glycals with BF3·OEt2, and display a remarkable reactivity leading to a variety of products. The substituent at O-6 in these glycals plays a pivotal role in directing the outcome of the transformations. Accordingly, 6- O-benzyl or 6- O-allyl groups cause a series of transformations resulting in the stereoselective formation of oxepanes through a process that involves an initial hydride transfer step from the allyl or benzyl substituent to the Ferrier-Nicholas cation. On the contrary, 6-OH derivatives undergo an overall ring contraction to branched tetrahydrofuran derivatives. 6- O-Silyl derivatives, in the presence of heteroaryl nucleophiles, were transformed into C-3 branched bis- C- C-glycosides, containing two of such molecules. [ABSTRACT FROM AUTHOR]

Diphosphino-functionalized 1,3-dialkylimidazolium salts react with KOH affording amine/formamide open-chain products, which fully revert to the imidazolium cation by treatment with a variety of acids or are converted to 2-imidazolones by noncatalyzed intramolecular dehydrogenative CN coupling, a process that is modulated by coordination of the phosphino functionalities to transition metals. [ABSTRACT FROM AUTHOR]

Cationic fluorocarbon emulsifier-free latex (CFEL) based on hexafluorobutyl methacrylate (FA), styrene, butyl acrylate, and methacrylatoethyl trimethyl ammonium chloride is successfully prepared in a new micellar system in which the fluorinated surface active monomer (FSM) based on isophorone diisocyanate, dodecafluoroheptanol, and allyl polyethylene glycol is used. The chemical structure of FSM is characterized by Fourier transform infrared spectroscopy, H-NMR, and its surface-active properties have been investigated by surface tension determinator. Besides, effect of FSM, FA, and also the curing temperature on the latex and film properties has been investigated by the coagulation ratio ( W), precipitation ratio ( W), Nano-ZS particle sizer, contact angle, and water absorption ratio, respectively. The results show that the FSM is successfully prepared. The CMC of FSM is 2.37 g L and the γ is 26.31mN m accordingly. The more FSM content makes more stable emulsion and have only little adverse effect on its film properties. When the FSM content increases from 1.05 to 13.11 %, the W and W decrease by 83.5 and 32.1 %, respectively, and the surface free energy ( γ) of CFEL film only increases by 8.3 %. The more FA content makes less stable emulsion but have favorable effect on its film properties. When the FA content increases from 0 to 25.11 %, the γ is decreased by 55.1 %. The curing temperature has much impact on film property. For example, the γ from 27.47 to 20.36 mJ · m when the curing temperature rises from 30 to 110 °C. [ABSTRACT FROM AUTHOR]

N-acyliminium-type cations are examples of highly reactive intermediates that are willingly used in organic synthesis in intra- or intermolecular α-amidoalkylation reactions. They are usually generated in situ from their corresponding precursors in the presence of acidic catalysts (Brønsted or Lewis acids). In this context, 1-aminoalkyltriarylphosphonium derivatives deserve particular attention. The positively charged phosphonium moiety located in the immediate vicinity of the N-acyl group significantly facilitates Cα-P+ bond breaking, even without the use of catalyst. Moreover, minor structural modifications of 1-aminoalkyltriarylphosphonium derivatives make it possible to modulate their reactivity in a simple way. Therefore, these types of compounds can be considered as smart synthetic equivalents of N-acyliminium-type cations. This review intends to familiarize a wide audience with the unique properties of 1-aminoalkyltriarylphosphonium derivatives and encourage their wider use in organic synthesis. Hence, the most important methods for the preparation of 1-aminoalkyltriarylphosphonium salts, as well as the area of their potential synthetic utilization, are demonstrated. In particular, the structure–reactivity correlations for the phosphonium salts are discussed. It was shown that 1-aminoalkyltriarylphosphonium salts are not only an interesting alternative to other α-amidoalkylating agents but also can be used in such important transformations as the Wittig reaction or heterocyclizations. Finally, the prospects and limitations of their further applications in synthesis and medicinal chemistry were considered. [ABSTRACT FROM AUTHOR]

We synthesized a novel cationic fluorinated polyacrylate latex (FLDH) with pendant long chain alkyl by copolymerization of perfluoroalkyl ethyl acrylate, lauryl methacrylate, dimethylaminoethyl methacrylate, and 2-hydroxypropyl acrylate. FTIR, 1H-NMR, TEM, DSC, and TGA were used to characterize the as-prepared FLDH. Then fine morphology, components, and hydrophobicity of films on silicon wafer and cotton substrates were investigated by scanning electron microscope, field emission scanning electronic microscope, atomic force microscope, X-ray photoelectron spectroscopy (XPS), contact angle meter, etc. Results showed that the FLDH particles had quasi-spherical core-shell structure with an average diameter of 144 nm. The core-shell FLDH film thus had two T g and its thermal property was improved compared to fluorine-free acrylate latex. FLDH could form a film on both the cotton fiber and silicon wafer substrate. At an amplification of <60,000 (of the original fiber) and the observation rule (working distance) of >100 nm, FLDH showed a smooth resin film on the treated fabric/fiber surface. However, as the observation rule decreased to 2 nm-almost a molecular lever-the FLDH film mostly exhibited an inhomogeneous structure and uneven morphology in its atomic force microscope images. There were many low or high peaks in FLDH topography. Consequently, in 5 μm2 scanning field, the root mean square roughness of FLDH film reached to 0.506 nm. XPS analysis indicated the perfluoroalkyl groups had the tendency to enrich at the surface. In addition, water contact angle of the treated fabric could attain 146.2°. FLDH do not influence whiteness of the treated fabric but will make it slightly stiff at high doses. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci., 2013 [ABSTRACT FROM AUTHOR]

Nano-structured rod-shaped particles of 6-line ferrihydrite were synthesized at ambient temperature under controlled conditions. The phase formation was confirmed through X-ray diffraction (XRD). Shape and size of the particles were observed by transmission electron microscopy. Batch sorption studies for Pb(II), Cd(II), and Cu(II) were carried out. A pseudo second order rate model fitted to the kinetic data was obtained for the three cations. By increasing the pH from 2.0 to 5.3, sorption of the three cations increased. At a pH of 5.3, maximum loading capacities were 0.4, 0.7, and 0.9 mmol g-1. The isothermal data for Pb(II) and Cu(II) fitted to the Langmuir model, the Cd(II) data to a Freundlich isotherm. Cu(II) uptake increased with an increase of Cl- concentration, that of Cd(II) decreased. The Pb(II) uptake capacity passed through a maxima of 25 mg L-1 Cl-. Presence of [image omitted] had beneficial effect on the sorption of both Cu(II) and Pb(II) but affected Cd(II) sorption adversely. Depending on the sorbed metal ion, XRD results showed disappearance, shift in d-values, or variation in relative intensities. The sorption from solutions containing two or all three of the metal ions exhibited some selectivity. [ABSTRACT FROM AUTHOR]

The fluorescent peptidocalixarenes, 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis(O-methyl-l-tryptophanylcarbonylmethoxy)calix[4]arene (1) and 5,11,17,23-tetra-tert-butyl-25,27-di(O-methyl)-26,28-bis(O-methyl-l-tryptophanylcarbonylmethoxy)calix[4]arene (2), were prepared by introducing tryptophan subunits at a lower calixarene rim. Coordination abilities of 1 and 2 towards Eu(III) and alkali metal cations were studied by spectrophotometric, spectrofluorimetric, conductometric and potentiometric titrations in acetonitrile at 25°C. Rather strong complexation was observed for smaller alkali metal cations Li+ and Na+ (log KLi1>6, log KLi2>6, log KNa1 = 8.25, log KNa2 = 6.94), and moderate for K+ (log KK1 = 5.09, log KK2 = 4.09). Larger Rb+ and Cs+ cations did not fit in the ion binding site of 1 so no complexation was detected, whereas the more flexible ligand 2 accommodated Rb+ cation (log KRb2 = 3.44). The fluorescence of 1 (λex = 280 nm, λem = 340 nm) was remarkably quenched by Eu(III). Stability constant of 1:1 (Eu3+:1) complex determined spectrofluorimetrically amounted to log KEu1 = 6.16. [ABSTRACT FROM AUTHOR]

The reaction of 2,6-dimethylpyridine with SbCl and HCl affords the title compound, the structure of which is ascertained by X-ray diffraction. The unit cell consists of one bridged SbCl anion and two 2,6-dimethylpyridinium cations. The trivalent antimony ion is bonded not only directly to chlorine anions, but also is coordinated with chlorine anions by secondary bonds. In the crystal, there exists infinite coordinated chains of [SbCl] anions running along the a axis, which link 2,6-dimethylpyridinium cations by N-H...Cl hydrogen bonds. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the bis(alkylammonium) tetrasulfidometalates, (EtNH3)2[MS4] (M = W 1, Mo 2), [BuNH3]2[MS4] (M = W 3; Mo 4) and (Et-enH2)[WS4] 1-en (Et-en = N-ethylethane-1,2-diamine), are reported. Compound 1 crystallizes in the centrosymmetric orthorhombic space group Pnma and its structure consists of discrete slightly distorted tetrahedral [WS4]2- of m symmetry, separated by two crystallographically independent (EtNH3)+ ions located on mirror planes. The carbons of one ethylammonium are disordered. Compound 1-en crystallizes in the centrosymmetric orthorhombic space group Pbca with all atoms situated in general positions. Its structure consists of discrete (Et-enH2)2+ and a slightly distorted tetrahedral [WS4]2- with the cations and anions linked by several weak hydrogen bonds. [ABSTRACT FROM AUTHOR]

Abstract  The synthesis and crystal structure of the salt (BPDT-TTF)2[W6O19] is described. The compound crystallizes in the triclinic space group P − 1 with a = 10.927(2) Å, b = 11.904(2) Å, c = 12.660(2) Å, α = 101.261(5)°, β = 115.174(5)°, and γ = 114.434(5)°. The bond length of the central C=C bond in BPDT-TTF is 1.384(17) Å, in accord with an oxidation state of +1 for the BPDT-TTF radical-cations and the observed stoichiometry between BPDT-TTF and [W6O19]2− which is 2:1. Index Abstract  The X-ray crystallographic structure of the radical cation salt (BPDT-TTF)2[W6O19] has been determined and its structural features, including examples of interatomic interactions, as well as its synthetic preparation are discussed. [ABSTRACT FROM AUTHOR]

Novel SO3H-functionalized ionic liquids bearing two alkyl sulfonic acid groups in the imidazolium cations were designed and successfully applied as catalysts for the one-pot Fischer indole synthesis in water medium. The sequence of the catalytic activity observed in the transformation was in good agreement with the Brønsted acidity order determined by the Hammett method. Various types of indoles from single-carbonyl ketones/aldehydes and cyclohexandiones were provided in 68–96% yields using the catalytic system of [(HSO3-p)2im][HSO4]/H2O. The indole products could be conveniently separated from the reaction mixture by filtration and the dissolved catalyst could be regenerated by treatment with a strongly acidic cation exchange resin, which meant the whole process was performed in water without using any organic solvents. [ABSTRACT FROM AUTHOR]

The cationic photoinitiator S,S-dialkyl-S-(3,5-dimethyl-4-hydroxyphenyl) sulfonium (called 4HPS simply) was synthesized in this article. The synthesis was proved successfully through FT-IR spectrum, 1H-NMR, and elemental analysis. The cure kinetics of photoinitiator/ ZH92-21 were studied through FT-IR spectrum combined with a high pressure mercury lamp. The concentrations of residual epoxy group, curing rate Rp and kinetics of polymerize termination were discussed. The results showed that the cure termination reaction of HPS photoinitiator/ZH92-21 was diradical-termination. [ABSTRACT FROM AUTHOR]

A series of five salts of carboamoyldicyanomethanide, C(CN)2(CONH2)−cdm, have been synthesised and structurally characterised using different cations; ammonium (1), methylammonium (2), dimethylammonium (3), trimethylammonium (4) and tetramethylammonium (5). These organic salts vary in the degree of hydrogen-bonding interactions that the cation can partake in with minimal change in the size of the cation. The structure of 1shows the NH4cation involved in extensive hydrogen bonding to the cdm anions to form a 3D network with minimal interaction between anions and the disruption of previously observed supramolecular synthons that occur between cdm anions. In contrast to this the structure of 5contains no hydrogen-bonding between cations and anions and leads to the formation of a corrugated sheet containing only interactions between neighbouring anions. The intermediate cases involving the MeH3N+(2), Me2H2N+(3) and Me3HN+(4) cations, display a 2D hydrogen bonded sheet in the case of 2and 1D chains in the structures of 3and 4. The structure of a larger tetraalkylammonium salt, (Et3MeN)cdm (6) contains a similar sheet network to that of the Me4N+compound with subtle changes due to the increase in size of the counter cation. The role of the steric bulk of the counter-cation has been further investigated by the synthesis of the benzyltrimethylammonium salt of cdm (7) in which the anions form a previously observed 1D chain motif and are well separated due to the bulk of the cation. [ABSTRACT FROM AUTHOR]

A new complex compound, bis[(18-crown-6)oxonium]tetrabromomanganese(II), 2[(H3O)+(18-crown-6)]·[MnBr4]2–, was prepared and studied by X-ray diffraction to reveal its unusual cubic crystal structure, space group Fd $$ \bar 3 $$ , a 20.424 Å, and Z 8. In this crystal structure, the complex cation [(H3O)+(18-crown-6)] the point symmetry $$ \bar 3 $$ position and the anion [MnBr4]2− with the point symmetry 23. The complex cation [(H3O)+(18-crown-6)] has a guest-host structure, and, unlike metal complexes by hydrogen bonds between H3O+ hydrogens and 18-crown-6 oxygens, rather than by coordination bonds. The pyramidal cation H3O+ in this crystal structure is statistically disordered, and the tetrahedral anion [MnBr4]2− is reorientationally disordered. [ABSTRACT FROM AUTHOR]

The complex [(NH2)2CSSC(NH2)2]2[OsBr6]Br2 · 3H2O is synthesized by the reaction of K2OsBr6 with thiocarbamide in concentrated HBr and characterized using electronic absorption and IR absorption spectroscopy. Its crystal structure is determined by X-ray diffraction. The crystals are orthorhombic, a = 11.730(2) Å, b = 14.052(3) Å, c = 16.994(3) Å, space group Cmcm, and Z = 4. The [OsBr6]2− anionic complex has an octahedral structure. The Os-Br distances fall in the range 2.483–2.490 Å. The α,α′-dithiobisformamidinium cation is a product of the oxidation of thiocarbamide. The S-S and C-S distances are 2.016 and 1.784 Å, respectively. The H2O molecules, Br−ions, and NH2 groups of the cation are linked by hydrogen bonds. [ABSTRACT FROM AUTHOR]

Type structure of (H3N–R–NH3)2I3BiI6, which consists of sheets of organic entities together with triiodide anions separated by layers of BiI6 octahedra, is defined by triiodide, hexaiodobismuthate, and organic diammonium. The prototype structure of (H3N(CH2)2SS(CH2)2NH3)2I3BiI6(1) can accommodate various changes according to the nature of the organic group, such as conformation, length or size. In (H3N(CH2)2SS(CH2)2NH3)2I3BiI6·0.5H2O (2), acentric symmetry resulted from the lattice water molecules render the SHG property. Whereas in (H3N(CH2)4NH3)2(I3)0.5(I(H2O)2)0.5 BiI6(3), water molecules are incorporated in the main framework by substituting two iodine atoms of I3− anion, in the structure of (H3NCH2(C6H10)CO2H)4(I3)2BiI6 H3O (4), pairs of linear triiodide entities [I3⋯I3]2−(d(I3−⋯I3−)= 3.77(1)Å) are observed, owing to the super-long diammonium cations of two trans-4-methylammonium cyclohexane carboxylic acid linked together via hydrogen bonding between carboxylate groups. [ABSTRACT FROM AUTHOR]

Many molecular charge transfer salts synthesised over the last 20 years contain alternating layers of organic donor cations and inorganic metal-complex anions. Here we survey some features of one of the most prolific families of such salts: (BEDT-TTF) 4 [AM(C 2 O 4 ) 3 ]. G, where BEDT-TTF is bis-ethylene-dithiotetrathiafulvalene, A is a monopositive cation, M a tri-positive cation and G an organic guest molecule. The roles of anion chirality, molecular conformational disorder and the formation of superlattice ordering of layer packing are emphasised. [ABSTRACT FROM AUTHOR]

Synthesis, crystal structure and physical properties of κ-(BEDO-TSeF) 2 I 3 , ( 1 ) are reported. 1 is the first example of a cation radical salt based on BEDO-TSeF, which is the latest chalcogen analogue of BEDT-TTF. [ABSTRACT FROM AUTHOR]

In this work, we report the syntheses and characterization of a new crystalline inclusion compound ofα-cyclodextrin using diquinuclidinium cation([Q2H]+)like guest. Elemental analysis,13C CP-MAS NMR spectroscopy and powder X-ray diffraction analysis confirm the inclusion process. The guest specie[Q2H]+corresponds to the adduct of a heterocyclic base with its conjugated cation in a symmetric linear arrangement[Q–H–Q]+. This complex[Q2H]+appears to be held in the host cavities only by weak van der Waals interactions. [ABSTRACT FROM AUTHOR]

Some cobalt spinels were synthesized under hydrothermal conditions, starting from metal chlorides, and Poly N-Acrolylquinazoline. The color properties in these systems mainly depend upon the preparative method and cation distributions, which have been determined by visible and near infrared absorption spectra. We observe the influence of tetrahedral and octahedral preference of cations such as Co2+, Cr3+, Mn3+ upon the formation and the color development of cobalt spinel polymers. All the samples prepared revealed the formation of single spinel with particle size at about 0.8-2.1 µ m; CoAl2O4 reveals kings blue, CoMn2O4 dark blue and CoCr2O4 bluish green. Cobalt blues developed giving deep absorption characteristic of tetrahedral Co2+ ions at about 550-680 nm; therefore, color changed from kings blue to bluish green in CoCr2O4, showing the absorption band of octahedral Cr3+ ions owing to the large excess octahedral crystal field stabilization energy. [ABSTRACT FROM AUTHOR]

Several cyclic and alicyclic C11 hydrocarbons have been shown to act as gamete releasing and/or attracting pheromones during sexual reproduction of brown algae (Phaeophyceae). The same compounds are also found in the essential oils of various plants, of which the occurrence of the cycloheptadiene-pheromone ectocarpene in Senecio isatideus (Compositae) is noteworthy. Administration of [3H]dodeca-3,6,9-tricnoic acid to cuttings of this plant leads to incorporation of radioactivity into ectocarpene. Double-bond-deuterated nona-3,6-dienoic acid is converted to fucoserratene, the pheromone of several Fucales, which is certainly not present among the hydrocarbons of Senecio. This proves that the pool of medium-chain, multiply unsaturated fatty acids includes precursors of all types of highly unsaturated hydrocarbons. Appropriately labelled (deuterium markers) fatty acid homologues were synthesized and applied to Senecio plantlets to unravel the mechanistic aspects. The results strongly suggest radical initiation of the pheromone biosynthesis by abstraction of a single hydrogen from a 1,4-pentadienyl segment of the fatty acid followed by oxidation to the corresponding cation. This causes fragmentation of the reactive intermediate into an olefine and carbon dioxide by neighbouring-group participation of the flanking double bonds. A tentative biosynthetic scheme is deduced from the experimental results which also sets the stereochemistry of the algal pheromones into a uniform mechanistic concept. [ABSTRACT FROM AUTHOR]

Two simple mercapto thiadiazole-based sensors have been synthesised by a convenient method and exhibit excellent sensitivity and selectivity for Hg2+ in DMSO/H2O (1:1, v/v) aqueous solution. The sensors react with Hg2+ to form stable complexes and the association constants, Ka, are 4.4 × 104 M-1 and 1.0 × 103 M-1, respectively. Furthermore, the detection limit of one sensor towards Hg2+ is 8.0 × 10-7 M. [ABSTRACT FROM AUTHOR]

The article focuses on total syntheses of englerin A which used cationic gold (I) complexes to influence the englerin's oxotricyclic core generation. It mentions that the plant-derived sesquiterpene englerin A is considered for chemical synthesis due to its low nanomolar inhibitory potential against renal cancer cell lines. It states that the gold (I)-catalyst and cyclization precursor selected for the syntheses were different wherein it forced the limit relative to gold-catalysis application.

The title compound, C2H6NO2+·C2Cl3O2−, crystallizes in the P41 space group with two glycinium cations and two trichloro­acetate anions in the asymmetric unit. The glycinium cations have nearly C s point-group symmetry which is only broken by the H atoms of the amine group. The trichloro­acetate anions show typical bond lengths and angles, one of the trichloro­methyl groups being disordered. Chains of alternating anions and cations run along the c axis. Within these chains, consecutive anion–cation pairs are bound via strong hydrogen bonds involving the carboxyl­ate anions and the carboxyl or amine groups of the cations. Weaker hydrogen bonds bind neighbouring chains together. [ABSTRACT FROM AUTHOR]

Highlights: [•] The covalent bonding of Cat-GGM was demonstrated with MALDI-TOF-MS. [•] Polyelectrolyte titration is a rapid method to measure the DS. [•] The DS of cationic GGM can be tailored. [•] Cationised GGM was acetylated, which made the product hydrophobic. [•] Cat-GGM can potentially be utilised as polyelectrolyte layers in packaging [ABSTRACT FROM AUTHOR]

Abstract: This study demonstrates a headspace gas chromatographic(HS-GC) technique for the determination of residual epichlorohydrin (ECH) and generated 1,3-dichloro-2-propanol (DCP) in synthesis process of 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHTAC). By a weight-based sampling method, coupled with significant dilution in 15.8% sodium sulfate and 0.1% silver nitrate mixed solution rapidly, the sample for HS-GC analysis is prepared. Based on the reaction stoichiometry, the conversion (R) of CHTAC during the synthesis process can be calculated from sampling weight and GC peak area. The results showed that the method has a good measurement precision (RSD<2.5%) and accuracy (recovery=101–104%) for the quantification of both ECH and DCP in the process samples. The present method is simple and accurate, which can be used for the efficient determination of the CHTAC conversion in the synthesis research. [Copyright &y& Elsevier]