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In this study, a low‐melting organic‐inorganic crystalline ionic liquid compound, N‐butyl pyridinium tetrachlorido ferrate (III) is described. The material can easily be synthesized using a one‐pot approach in an ionic liquid medium. Single‐crystal X‐ray diffraction confirms that the basic inorganic block is [FeCl4]−, which is counterbalanced by an N‐butyl pyridinium cation. The compound exhibits a melting point of 37.6 °C by differential scanning calorimetry, which is among the lowest values for a pyridinium‐based metal‐containing ionic liquid. The material shows promising electrochemical behavior at room temperature in both aqueous and nonaqueous solvents, and at elevated temperatures in its pure liquid state. Given its appreciable solubility in both water and acetonitrile, the compound can act as a redox‐active species in a supporting electrolyte for redox flow battery applications. These classes of low‐melting ionic solids with long‐range order and interesting electrochemical applications are potential candidates for a range of green energy storage and harvesting systems. [ABSTRACT FROM AUTHOR]

Herein, we report on the preparation of liquid dimeric lanthanide(III)‐containing compounds. Starting from the design of dimeric solids, we demonstrate that by tuning of anion and cation structures we can lower the melting points below room temperature, whilst maintaining the dimeric structure. Magnetic measurements could establish the spin‐spin interactions of the neighboring lanthanide(III) ions in the liquid state at low temperatures, and matched the interactions of the analogous crystalline solid compounds. [ABSTRACT FROM AUTHOR]

Uranyl complex dissolved in room-temperature ionic liquids has diagnostic absorption and emission spectra that has allowed the identification of the symmetry and geometry of the complex. The uranyl complexes are examined in imidazolium and pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids.

A general method is described for the synthesis and purification of hydrophilic ionic liquids, choline saccharinate and choline acesulfamate. The analysis has shown that choline saccharinate and choline acesulfamate are ionic liquids with a low toxicity, as these ionic liquids are composed of animal feed additives and of additives for human nutrition.

A series of D–π–A type azobenzenes with a ferrocenyl/ferrocenylethynyl electron donor at the para/meta-position have been synthesized and characterized by electrochemistry and UV-vis spectroscopy. Compared to the D–π type meta-ferrocenyl/ferrocenylethynyl azobenzenes, the photoisomerization properties of D–π–A type meta-ferrocenyl/ferrocenylethynyl azobenzene are significantly improved. The photoisomerization properties of D–π–A type meta-ferrocenyl azobenzene are significantly different from those of D–π–A type para-ferrocenyl azobenzene, due to the electronic communication influenced by the substitution position of the redox center on the azobenzene moiety. Among the derivatives, compound 17 exhibits the highest amount of the cis form (97%) in the photostationary state (PSS) upon UV light (365 nm) irradiation. Compounds 13 and 15–17 exhibit excellent fatigue resistance and reversibility upon several reversible isomerization cycles. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of near-infrared (NIR) emitting complexes of Nd(III), Er(III) and Yd(III) based on hexacoordinate lanthanide ions with an aryl functionalized imidodiphosphinate ligand, tpip, are described. The results indicate the effective shielding of the lanthanide by the twelve phenyl groups of the tpip ligands and the reduction of high-energy vibrations in close proximity to the lanthanide, which are the two important features in the design of NIR emitting lanthanide complexes.

Six ionic liquids based on the 1-butyl-3-methylimidazolium cation have been studied. As anions Cl-, Br-, I-, [NCS]-, [N(CN)2]-, and [BF4]- were selected. The electrical conductivities were determined between 173 and 393 K based on impedance measurements in the frequency range from 0.1 to 107 Hz. The electrical conductivity increases, whereas the glass transition temperature, the fragility, and the low temperature activation energy decrease with increasing anion size. The results can be understood from the changing anion-cation interaction strength with changing anion size and from the energy landscape interpretation of the glass transition dynamics. [ABSTRACT FROM AUTHOR]

The electrical conductivities of 1-alkyl-3-methylimidazolium tetrafluoroborate ionic liquids and of 1-hexyl-3-methylimidazolium ionic liquids with different anions were determined in the temperature range between 123 and 393 K on the basis of dielectric measurements in the frequency range from 1 to 107 Hz. Most of the ionic liquids form a glass and the conductivity values obey the Vogel-Fulcher-Tammann equation. The glass transition temperatures are increasing with increasing length of the alkyl chain. The fragility is weakly dependent on the alkyl chain length but is highly sensitive to the structure of the anion. [ABSTRACT FROM AUTHOR]

The syntheses, structures and spectroscopic properties of the two new rare-earth metal halide ortho-oxomolybdates YF[Mo[O.sub.4]] and YCl[Mo[O.sub.4]] are reported. Both structures were found to contain [[Y.sub.2][X.sub.2]].sup.4+] units in the shape of planar rhombuses, while the [Eu.sup.3+]-doped fluoride derivatives exhibited red luminescence.

The complex formation of the uranyl ion with chloride ions in acetonitrile is examined by factor analysis of ultraviolet-visible absorption and U [L.sub.3] edge EXAFS (extended X-ray absorption fine structure) spectra. The U(VI) coordination of the solution species [U[O.sub.2][Cl.sub.2]([H.sub.2]O)[(MeCN).sub.2]] has changed during the crystallization of replacing one MeCN molecule with a bridging [[mu].sub.3].O atom in the tetramer.

The ferrocene-derivatives bis(ferrocenyl-ethynyl)-1,10-phenanthroline ([Fc.sub.2]phen) and ferrocenoyltrifluoroacetone (Hilta) is used to synthesize ferrocene-containing rate earth beta-diketonate complexes. It is found that the presence of the ferrocene groups makes the rare-earth complexes hydrophobic and well-soluble in apolar organic solvents.

The unique absorption properties of the 9-hydroxyphenalen-1-one (HPHN) ligand are explored to obtain visible-light-sensitizable rare-earth complexes in 1:3 and 1:4 metal-to-ligand ratios. The X-ray crystal structures of the tris complexes have shown solvent coordination to the central rare-earth ion, whereas in the tetrakis complexes, the four [PHN.sup.-] ligands form a protective shield around the central ion, preventing small solvent molecules from coordinating to the rare-earth ion, at least in the solid state.

[Hbet][Tf2N] is a versatile task-specific ionic liquid that could be used for the selective solubilization of metal oxides and metal salts. The concept of solubilizing metal oxides in a task-specific ionic liquid is based on the presence of acidic functional groups in the ionic liquid.

A study reports the first lanthanide-containing ionic liquids based on the 1-butyl-3-methylimidazolium (BMIM) cation and lanthanide thiocyanate anions of the general formula [[Ln[(NCS).sub.x][(H2O).sub.y].sup.3-x]. The compounds are transparent liquids at room temperature and the crystal structure of [BMMIM.sub.4][La(NCS)7](H2O)] indicates that hydrogen bonding might influence the melting points.

The complex structural chemistry of rare-earth quinolinates is explored in the study. Most synthetic methods to obtain rare-earth quinolinates yield a mixture of different species.

Deep eutectic solvents (DESs) based on choline chloride, chromium chloride, and their mixtures with water are emerging as one of the most promising sustainable alternatives to the banned and carcinogenic Cr(vi) electroplating process (REACH Annex XVII). However, the coordination chemistry of these liquids is still largely unresolved and only a limited number of compositions have been studied to date. Hence, an in-depth study using a large range of techniques was carried out on the complete composition range of stable liquids at room temperature. This resulted in detailed knowledge regarding the concentration profiles of all constituting components, and the discovery of an important link between the coordination chemistry and the conductivity of the mixtures. Additionally, a tool was developed to obtain 10 different variables and concentrations by the measurement of a single UV/Vis absorption spectrum. Based on these results, researchers in both industry and academia will be able to select a certain DES–water mixture to obtain specific characteristics, as well as concentrations of the constituting components and complexes. Additionally, these mixtures can be closely monitored before, during and after electroplating, by means of UV/Vis absorption spectroscopy. These results form an important step towards the industrial application of these promising green electrolytes as alternatives to the wide-spread and recently banned carcinogenic Cr(vi) electroplating baths. [ABSTRACT FROM AUTHOR]

Molecular docking studies of toluene dioxygenase led to the prediction that angular and lateral cis‐dihydroxylation of tricyclic arene and heteroarene substrates could occur. Biotransformations of biphenylene, dibenzofuran, carbazole and dibenzothiophene, using Pseudomonas putida UV4 whole cells, expressing toluene dioxygenase, confirmed that both angular and lateral cis‐dihydroxylation had occurred in the predicted regioselective and stereoselective manner. The toluene dioxygenase‐catalysed (Pseudomonas putida UV4) biotransformation of dibenzofuran was optimized, to produce 1,2‐dihydrodibenzofuran‐1,2‐diol as the major metabolite in excellent yield. 2‐Hydroxydibenzofuran, resulting from dehydration of 1,2‐dihydrodibenzofuran‐1,2‐diol, was also found to undergo cis‐ dihydroxylation to give a very minor cis‐dihydrodiol metabolite. The enantiopurity (>98% ee) and (1R,2S) absolute configuration of the major dibenzofuran cis ‐dihydrodiol was rigorously established by catalytic hydrogenation and formation of methoxy(trifluoromethyl)phenylacetate derivatives and by X‐ray crystallography of an epoxide derivative. Biotransformation of carbazole yielded anthranilic acid as the major metabolite and was consistent with angular cis‐dihydroxylation. Synthesis of a cis‐ diol epoxide derivative showed that the main cis‐dihydrodiol metabolite of dibenzofuran has potential in the chemoenzymatic synthesis of natural products. [ABSTRACT FROM AUTHOR]

New preorganised 1,2-diamide functionalised, bidentate ligand-embedded hydrophobic ionic liquids (DAILs) were synthesised, which enabled efficient extraction of lanthanides from an aqueous phase. The selective metal binding ability of the functionalised ionic liquid was examined by NMR, FTIR and a structure optimisation calculation. The selective liquid–liquid extraction behavior with DAILs was demonstrated. [ABSTRACT FROM AUTHOR]

In the last decade, deep eutectic solvents (DES) have risen as promising and cheap alternatives for the often expensive and moisture-sensitive ionic liquids. For the application in metal processing industries such as hard chrome plating, still very little is known of the behavior of metal ions in these types of liquids. Therefore, we use the model-free Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) method to study Cr(iii) as sustainable alternative to the hazardous Cr(vi) and obtain reference UV/Vis spectra of chromium(iii)chlorides in several aqueous solutions and in water–DES mixtures. In addition, the results have been confirmed by EXAFS measurements. We observe that in the DES ethaline, ethylene glycol ligands are coordinating with the chromium(iii) metal ions and hence, different UV/Vis reference spectra are obtained, compared to those in aqueous solutions. Additionally, concentration profiles provide a tool for tuning the coordination chemistry, based on the choice of the appropriate DES mixture or aqueous solutions. Consequently, valuable UV/Vis reference spectra for some known and unknown chromium chloride complexes in several aqueous solutions and DES–water mixtures were obtained, which showed that the coordination chemistry in these liquids can be considerably different and comparison should be done with great care. [ABSTRACT FROM AUTHOR]

An efficient and green protocol for highly selective reduction of α,β‐unsaturated aldehydes and ketones at room temperature is described in a range of ionic liquids, in the absence of noble metal catalysts, by using NaBH4 as reducing agent. Most notably, using [P6,6,6,14][N(CN)2] ionic liquid, in absence of organic solvent, within 10 min, 97% conversion of cinnamaldehyde was achieved with 100% selectivity towards cinnamyl alcohol. The ionic liquid was easily recycled without any noticeable decline in activity. The reduction protocol was further extended to a variety of α,β‐unsaturated aldehydes and ketones. A novel protocol for highly selective reduction of a range of α,β‐unsaturated aldehydes and ketones at room‐temperature has been developed. In the absence of organic solvent, using [P6,6,6,14][N(CN)2] ionic liquid, 100% selectivity to cinnamyl alcohol at 97% cinnamaldehyde conversion was achieved within 10 minutes. [ABSTRACT FROM AUTHOR]

PX3 compounds (X=Cl, Br, I) in imidazolium halide ionic liquids combine with the anion Z (Z=Cl, Br, I) of the solvent to form [PX3Z]− complex anions. These anions have a sawhorse shape in which the lone pair of the phosphorus atom fills the third equatorial position of the pseudotrigonal bipyramid. Theoretical results show that this association remains incomplete due to strong hydrogen bonding with the cations of the ionic liquid, which competes with the phosphorus trihalide for interaction with the Z− anion. Temperature‐dependent 31P NMR experiments indicated that the P−Z binding is weaker at higher temperature. Both theory and experiment evidence dynamic exchange of the halide anions at the phosphorus atom, together with continuous switching of the ligands at the phosphorus atom between equatorial and axial positions. Detailed knowledge of the mechanism of the spontaneous exchange of halogen atoms at phosphorus trihalides suggests a way to design novel, highly conducting ionic‐liquid mixtures. Dynamic halide exchange: Phosphorus trihalides PX3 form [PX4]− anions in 1,3‐dialkyl imidazolium halide ionic liquids (HMIM in scheme). The dynamic exchange of the anions at the phosphorus atom shows typical characteristics of a Grotthuss‐like diffusion mechanism and potentially offers a way to design highly conducting materials. [ABSTRACT FROM AUTHOR]

A series of new cationic palladium(II) complexes were prepared and studied for their ability to catalyze the Wacker-type oxidation of styrenes to their corresponding acetophenones using O2 as the sole oxidant. Catalysts are active at room temperature and the study highlights the importance of solvent choice and the need for ligand development in improving catalyst performance. [ABSTRACT FROM AUTHOR]

Zwitterionic salts are hybrid materials, incorporating some characteristics of zwitterions and of ionic liquids, e.g. numerous options for structural design and functionalisation. They are comprised of cations and anions in which an additional zwitterionic moiety is embedded into either the cation or the anion. Such materials are characterised by having extended polar domains and high hydrophilicity. Here, we present results from the study of novel zwitterionic salts that are representative examples of this class of materials and illustrate the potential to exploit their functionalities and high hydrophilicity. [ABSTRACT FROM AUTHOR]

A unified total synthesis of the GRP78-downregulator (+)-prunustatin A and the immunosuppressant (+)-SW-163A based upon [1 + 1 + 1 + 1]-fragment condensation and macrolactonization between O(4) and C(5) is herein described. Sharpless asymmetric dihydroxylation was used to set the C(2) stereocenter present in both targets. In like fashion, coupling of the (+)-prunustatin A macrolide amine with benzoic acid furnished a JBIR-04 diastereoisomer whose NMR spectra did not match those of JBIR-04, thus confirming that it has different stereochemistry than (+)-prunustatin A. [ABSTRACT FROM AUTHOR]