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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]

8-Hydroxy-6-methyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine was formed selectively in high yields from N-(β-methallyl)imidazole by a tandem hydroformylation–cyclization sequence, representing a novel one-pot catalytic synthesis of bicyclic imidazole derivatives. [ABSTRACT FROM AUTHOR]

The enantioselective intramolecular alkylation of substituted imidazoles with enantiomeric excesses up to 98 has been accomplished by rhodium catalyzed C–H bond functionalization with S,S′,R,R′TangPhos as the chiral ligand. [ABSTRACT FROM AUTHOR]

The development of convenient and practical synthetic strategies for constructing bioactive molecules without metal residues is of great interest in organic synthesis. Herein, a metal-free, operationally simple, and scalable electrooxidation-induced three-component cross-coupling method to access 3-thio/selenophosphorylated imidazole derivatives from readily available isothiocyanates/isoselenocyanates, isocyanates, and H-phosphonates is first reported. More than 30 examples have been provided with good to moderate yields. Importantly, the readily accessible compounds could be used as pesticides (wheat anti-locust) with good biocompatibility (5d-stimulated RAW 264.7 macrophages, IL-6 = 5.3 pg mL−1, THF-α = 79.8 pg mL−1), reiterating the importance of the developed electrochemical methodology. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis and the physical characterization of a new family of chelating ionic liquids carrying a terpyridine fragment suitable for metal extraction. [ABSTRACT FROM AUTHOR]

A family of heteronuclear metal organic frameworks (MOFs) using lanthanide and transition metal ion based on a rigid ligand of substituted imidazoledicarboxylic acid, namely, {[Ln2Zn2 (|3-Hmimda)2 (μ3-mimda)2-4H2O]n-mn H2O}, Ln = Nd, m = 2 (1), Ln = Ho, m = 3 (2), Ln = Er, m = 2 (3), Ln = Yb, m = 3 (4), [Tb2Co2(μ3-Hmimda)2 (μ3-mimda)2-4H2O]n-2nH2O} (5) and [Dy2Co2 (μ3-Hmimda)2 (μ3-mimda)2-4H2O]n-nH2O} (6), (H3mimda = 1H-2-methyl-4,5-imidazole-dicarboxylic acid), have been developed and characterized. All the complexes (except for a little disparity for 1) are isostructural, and all crystallize in the monoclinic system. They possess an extended reticular-like porous structure constructed from corrugated 2D layers. Direct current (dc) magnetic susceptibility measurements for 1 - 5 indicated depopulation of the Stark components at low temperature and/or possible weak anti-ferromagnetic interactions within heteronuclear MOFs. Alternating current (ac) susceptibility studies reveal that the Dy(iii)--Co(ii) complex exhibits both possible ferromagnetic couplings and frequency-dependent out-of-phase signals, behaviour of single-ion magnet nature. Fluorescence properties of series complexes both in near-infrared (NIR) and visible regions have been comparatively studied. [ABSTRACT FROM AUTHOR]

Presented here are three imidazole-linked tetrahedral zinc phosphonate frameworks based on a special ligand 2-(1-imidazole)-1-hydroxyl-1,1'-ethylidenediphosphonic acid (= ImhedpH4) with both an organic imidazole linker and inorganic phosphonate groups. Three new compounds, namely, [Zn2(ImhedpH2)2(ox)]- (H2ppz) (1), Zn3(ImhedpH)2(H2O)4 (2) and [Zn3(Imhedp)2](H2ppz) (3) (ox = oxalate and ppz = piperazine), were obtained by hydrothermal synthesis and structurally characterized by single-crystal X-ray diffraction. Compound 1 shows a chain structure with the ox ligands linking the [Zn2(ImhedpH2)2] units, and the resulting chains are further connected to form a 3D structure through the strong N-H⋯O and O-H⋯O hydrogen bonds between the neighboring chains. Compound 2 displays an inorganic layer structure with dangling imidazole units, where these protonated imidazoles also act as pillars between adjacent inorganic layers. Compound 3 features an unusual chiral three-dimensional (3D) Zn-Imhedp framework with guest H2ppz2+ cations. It can be topologically represented as a 4-connected qtz network. Furthermore, the luminescent properties of the three compounds were investigated in the solid state. [ABSTRACT FROM AUTHOR]

Hydantoins have been known as medicinally active compounds since the 1940s and thiohydantoin derivatives are currently undergoing clinical trials as potent androgen receptor antagonist drugs. Control of solid state properties including the formation of drug polymorphs is important to the pharmaceutical industry, and frequently results from different H-bonded motifs. N–H thiohydantoins show formation of H-bonded arrays in the solid state. Two novel and five known thiohydantoin derivatives were synthesised viareaction of alkyl isothiocyanates with amino acid methyl esters. X-Ray crystallographic data were obtained for all seven compounds showing that four of the structures contain hydrogen bonded dimeric units linked viaN–HS interactions and three of the structures have N–HO linked H-bonded chains. [ABSTRACT FROM AUTHOR]

A series of 2,4,5-triarylimidazoles was synthesized from a new, highly efficient and green method. The reaction is performed in water, without the presence of any catalyst, and under microwave irradiation. This provides new opportunities for the rapid screening of a wide range of compounds, either for the development of new drugs, or original compounds for the material scientist. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are being considered as a promising class of potentially environmentally-friendly (“green”) solvents and materials for use in a variety of applications. However, ionic liquids are conventionally synthesized by batch, without known kinetics, in non-sustainable solvents. For ILs to be a truly “green” technology for widespread use, they must themselves be made in a correspondingly benign manner for low cost, as enabled by process development. This investigation will illustrate the kinetics and large solvent effects in the synthesis of 1-hexyl-3-methyl-imidazolium bromide in 10 different solvents: acetone, acetonitrile, 2-butanone, chlorobenzene, dichloromethane, dimethyl sulfoxide (DMSO), ethyl formate, ethyl lactate, methanol, and cyclopentanone. The kinetic rate constant for the synthesis in DMSO is over an order-of-magnitude larger than that in methanol. While the kinetic rate of these type of SN2 reactions is generally known to increase with solvent “polarity”, multi-parameter solvent descriptors, e.g.of Kamlet and Taft, are required to quantify these effects in a Linear Solvation Energy Relationship. These relationships are used with environmental and toxicity databases, such as the Rowan Solvent Selection Table, to rapidly optimize the solvent for favorable kinetics and minimal human and environmental impact. [ABSTRACT FROM AUTHOR]