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Ionic liquid (1-ethyl-3-methylimidazolium acetate, [C2C1im][AcO])-copper(ii) diacetate monohydrate-water-air (O2) systems have been investigated by (13)C NMR, EPR, spectrophotometry, HPLC, and synthetic chemistry methods at different temperatures. The C-H bond activation of [C2C1im](+) with the formation of the unusual dication 1,1'-diethyl-3,3'-dimethyl-2,2'-biimidazolium ([(C2C1im)2](2+)) at 50 °C and 1-ethyl-3-methyl-1H-imidazol-2(3H)-one (C2C1imO) at 50-85 °C was revealed. Two new complexes with the above compounds, [(C2C1im)2][Cu(AcO)4] and Cu2(AcO)4(C2C1imO)2, were isolated from the systems and characterized by X-ray structural analysis. Catalytic cycles with the participation of copper(ii) acetate and dioxygen and the production of [(C2C1im)2](2+) and C2C1imO have been proposed. The catalysis presumably includes the formation of the Cu(II)(O2)Cu(II) active centre with μ-η(2):η(2)-peroxide bridging in analogy with tyrosinase and catechol oxidase activity.

Promising membrane transport and separation systems for selected dicarboxylic, α-hydroxy- and α-amino acids based on thiacalixarene platform have been developed. For the first time, p-tert-butyl thiacalix[4]arenes functionalized at the lower rim with aminophosphonate fragments have been obtained and characterized. As was established by UV–vis spectroscopy, membrane extraction and HPLC, the substitution of amino groups by α-aminophosphonate units significantly enhances the selectivity of host molecules that bind to aspartic and glycolic acids. The aminophosphonate compounds synthesized can be used in the development of sensors and systems employed in the purification and separation of organic acids. Copyright © 2013 John Wiley & Sons, Ltd.

A series of diverse binuclear and mononuclear cyclometalated palladium(II) complexes of different structure was investigated by electrochemical techniques combined with density functional theory (DFT) calculations. The studies including cyclic and differential pulse voltammetry, X-ray structure analysis and quantum chemical calculations revealed a regularity of the complexes oxidation potential on the metal–metal distance in the complexes: the larger Pd–Pd distance, the higher oxidation potentials. The reduction potentials feature unusually high negative values while no correlation depending on the structure could be observed. These results are in a good agreement with the electron density distribution in the complexes. Additionally, ESR data obtained for the complexes upon oxidation is reported.

An efficient PBu3-catalyzed α-addition of the P(O)–H bond to ethyl phenylpropiolate has been developed. This strategy offers a facile method for the preparation of synthetically useful alkenyl phosphonates and phosphinates proceeding under neutral reaction conditions with high atom economy.

© 2016 Taylor & Francis Group, LLC.New stable dicarboxylate phosphabetaines were synthesized by the phosphorylation of a series of unsaturated carboxylic acids. Interaction of 3-(diphenylphosphonio)propionic acid with unsaturated monocarboxylic acids leads to the formation of stable dicarboxylate phosphabetaines 1–7. The structure of the isolated compounds was determined by IR and NMR spectroscopy, X-ray single crystal diffraction studies, and elemental analysis. Their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. All of the synthesized compoundswere tested for their antibacterial and anti-Candida activity.

The crude extracts of the Madagascan soft corals Sinularia vanderlandi and Sinularia gravis (Alcyoniidae) showed activity against Plasmodium falciparum which led us to study their chemical constituents. The new cadinane-type sesquiterpenoid vanderlandin (1) has been obtained from S. vanderlandi along with 24-methylenecholesterol (2). Four new compounds, the spatane-type diterpenoid gravilin (3), the monoalkylmonoacylglycerol 4, the dihomoditerpenoid ketone 5, and isodecaryiol (9), along with the three known compounds (+)-(S)-geranyllinalool (6), (−)-(R)-nephthenol (7), and 11,12-epoxysarcophytol A (8) have been isolated from the methanol extract of S. gravis. The structures were elucidated based on extensive spectroscopic methods, in particular various 2D NMR techniques. The structure of isodecaryiol (9) including its absolute configuration could be confirmed by X-ray diffraction.

A novel electrocatalytic process is presented for the direct C—H phosphonation of 2-phenylpyridine to give the phosphonic acid (III).

Novel 2,4-diorganyl 1,3,2,4-dithiadiphosphetane-2,4-disulfides were prepared by the reactions of tetraphosphorus decasulfide with butylphenyl ether or 3-brominephenyl-1-isoamyl ether in 1,2-dichlorobenzene. Their structures were established by X-ray single crystal diffraction. Chiral S-trimethylsilyl dithiophosphonates were prepared by the reactions of 2,4-diorganyl 1,3,2,4-dithiadiphosphetane-2,4-disulfides with trimethyl silyl ethers of monoterpenols. Unsaturated S-trimethylsilyl dithiophosphates were synthesized by the reactions of 2,4-diorganyl 1,3,2,4-dithiadiphosphetane-2,4-disulfides with O-trimethylsilyl ethers of geraniol, nerol and (R,S)-linalool. S-Esters of dithiophosphonic acids, which possessed antimicrobial activity, were prepared by the reactions of chiral S-trimethylsilyl dithiophosphonates with orthoformiates, acetals and thioacetals.