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Electrosynthesis of imidazolium carboxylates.
2013
Synthesis of imidazolium carboxylate compounds was efficiently achieved by electrochemical reduction of imidazolium precursors under very mild conditions.
Massenspektrometrische Untersuchungen an Edukten für die Synthese H2-aktiver Substanzen
1982
Unter den Bedingungen der Elektronenstosionisation wurden 4-[(2-Aminoethoxy)-methyl]-5-methyl-imidazo (1), die Imidazolderivate mit N-substituierter Ethylendiamin-Struktur 2–5 sowie die Imidazolcarboxamide 6–8 massenspektrometrisch untersucht. Der Mechanismus der konkurrierenden Bindungsspaltungen und der Umlagerungsprozesse wird formuliert. Die Wechselwirkung der funktionellen Gruppen sowie deren Einflus auf das Fragmentationsverhalten der Substanzen wird beschrieben und ein Schema der Hauptfragmentierungswege vorgeschlagen. Mess Spectrometry of Reactants for the Synthesis of H2-Active Compounds 4-[(2-Aminoethoxy)methyl]-5-methylimidazole (l), the imidazoles 2-5 with N-substituted ethylene…
Chemical transformations of a crystalline coordination polymer: a multi-stage solid–vapour reaction manifold
2013
In its crystal structure the one-dimensional coordination polymer [Ag4(O2C(CF2)2CF3)4(TMP)3]n (1) (TMP = 2,3,5,6-tetramethylpyrazine) adopts a zig-zag arrangement in which pairs of silver(I) centres bridged by two fluorocarboxylate ligands are linked alternately via one or two neutral TMP ligands. This material can reversibly absorb/desorb small alcohols (ROH) in single-crystal-to-single-crystal transformations, despite the lack of porosity in the crystals, to yield a related material of formula [Ag4(O2C(CF2)2CF3)4(TMP)3(ROH)2]n (1-ROH). The absorption process includes coordination of the alcohol to silver(I) centres and, in the process, insertion of the alcohol into one-quarter of the Ag–O…
Microwave-Assisted Synthesis of Polysubstituted 4-Quinolones from Deprotonated α-Aminonitriles
2010
The α-alkylation of deprotonated N-aryl-α-aminonitriles with α-bromoesters furnishes intermediates that can be cyclized to 4-quinolones upon microwave irradiation. Alternatively, base-induced dehydrocyanation of the alkylation products furnishes enaminoesters, which can, for example, be converted into quinoline-3-carboxylates.
Electrochemical Synthesis of Aryl Methoxymethyl Ethers
2019
Correlative Analysis of the Photosynthetic Capacity and Different Components of the Photosynthetic Apparatus
1984
The majority of higher plants is able to adapt to the ecological factor light in a wide range. Depending on the light intensity and the light quality during growth, plant with an equal genotype develop into so-called low light and high light forms. The photosynthetic adaptation to different light conditions involves complex, balanced changes of many leaf features. The changes of physiological factors of photosynthesis includes differences in the CO2 conductance, in the Calvin cycle enzymes, the capacity of electron transport, the photophosphorylation and the pigments (Boardman, 1977; Wild, 1979; Bjorkman, 1981; Lichtenthaler et al., 1981). The adaptation of individual plants or leaves to lo…
Recent Scientific and Technological Developments in Electrochemical Carboxylation Based on Carbon Dioxide
2010
Properties of the Nafion membrane impregnated with hydroxyl ammonium based ionic liquids
2012
In this work, the Nafion 112 membrane impregnated with nine various hydroxyl ammonium based ionic liquids have been investigated. The used ionic liquids were combined from hydroxyl ammonium cations (2-hydroxyethylammonium/HEA, bis(2- hydroxyethyl)ammonium/BHEA, tris(2-hydroxyethyl)ammonium/THEA) and carboxylate anions (formate, acetate, lactate). The membranes are characterized by conductivity and thermal stability measurements. It was found, that almost all composites have 10 times higher ion conductivity than a pure Nafion 112 at 90 ?C in ambient environment due to the higher thermal stability. The thermal stability of Nafion membrane was increased by all studied nine ionic liquids. In th…
ChemInform Abstract: Catalytic Aerobic Oxidative Decarboxylation of α-Hydroxy Acids. Methyl Mandelate as a Benzoyl Anion Equivalent.
2010
Abstract The monomeric square-planar cobalt(III) complex of bis- N,N ′-disubstituted oxamides catalyses the oxidative decarboxylation of α-hydroxy acids with molecular oxygen/pivalaldehyde with very good yields. This reaction offers an interesting alternative in the use of methyl mandelate as a convenient benzoyl anion equivalent.
Über die photosensibilisierte autoxydation von polyvinylalkohol
1968
Polyvinylalkohol wurde in wasriger Losung bei 30°C unter Belichtung mit einer Quecksilberhochdrucklampe einer mit benzophenn-3.3′-disulfonsaurem Natrium photosensibilisierten Autoxydation unterworfen. Als Reaktionsprodukte wurden Wasserstoffperoxid, Sauren und Kohlendioxid ermittelt. Unter den gewahlten Reaktionsbedingungen werden die Makromolekule statistisch abgebaut. Viskositatsmessungen und analytische Bestimmungen zeigen, das pro Spaltung der polymerkette nur eine Carboxylendgruppe entsteht. Ein Reaktionsmechanismus wird diskutiert. Polyvinylalcohol was oxidized in water solution at 30°C by irradiation with a mercury high pressure lamp and benzophenon-3.3′-disodiumdisulfonate as sensit…