Volker Kahlenberg

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Five new 5,5'-azotetrazolate salts (amminsilver, trimethylsulfonium, tetramethyl-phosphonium, trimethylsulfoxonium, 2-(hydroxyethyl)trimethylammonium) were prepared and characterized. The crystal structures were determined by X-ray diffraction. Interactions between the ions are identified and discussed. The sensitivities of the highly energetic silver salt(More)
Four (57)Fe-labeled tetrachloroferrates(III) of organic cations (1-butyl-3-methylimidazolium, 1-allyl-3-methylimidazolium, 1-methyl-1-propylpyrrolidinium, tetraphenylphosphonium) were examined by temperature-dependent Mössbauer spectroscopy. The hyperfine and dynamic parameters of the iron(III) site were determined. Single crystal X-ray diffraction data of(More)
An improved synthesis of the Cholesteryl Ester Transfer Protein inhibitor dalcetrapib is reported. The precursor disulfide was reduced (a) by Mg/MeOH or (b) by EtSH/DBU/THF. The resulting thiol was acylated (a) by a known procedure or (b) in a one-pot process. Impurities were removed (a) by dithiothreitol (DTT) or (b) by oxidation using H 2 O 2. Dalcetrapib(More)
The crystal structures of four salts of 1,4-diazabicyclo[2.2.2]octane (DABCO) and 5-aminotetrazole are described. Anhydrous 1:1 (Pbca, R gt = 0.041) and 1:2 (P 1 , R gt = 0.038) salts form hydrogen-bonded layers of anions and cations. The monohydrate of the 1:1 compound (P2 1 /c, R gt = 0.038) shows infinite chains of DABCO cations and an undulated layer of(More)
Starting from a synthetic sample with composition Al2(SO4)3·16.6H2O, the high-temperature- and moisture-dependent behavior of alunogen has been unraveled by TGA measurements, in situ powder X-ray diffraction as well as by gravimetric moisture sorption/desorption studies. Heating experiments using the different techniques show that alunogen undergoes a first(More)
1,3-Disubstituted 2-azidoimidazolium salts (substituents = methyl, methoxy; anion = PF 6) reacted with N-heterocyclic carbenes to yield yellow 2-(1-(azolinylidene)triazen-3-yl)-1,3-R 2-imidazolium salts (azole = 1,3-dimethylimidazole, 1,3-dimethoxyimidazole, 4-dimethylamino-1-methyl-1,2,4-triazole; R = methyl, methoxy; anion = PF 6). Crystal structures of(More)
Bis(1,4-diamino-1,2,4-triazolium) sulfate (1) was obtained from the corresponding chloride by ion metathesis using Ag 2 SO 4. Further metathesis with barium 5,5 1-azotetrazolate yielded bis(1,4-diamino-1,2,4-triazolium) 5,5 1-azotetrazolate (2). Numerous NH¨¨ ¨ N and NH¨¨ ¨ O interactions were identified in the crystal structures of 1 and 2. Both compounds(More)
The title compound, (C10H21N3)[CuCl4], is composed of one 1-[2-(di-ethyl-aza-nium-yl)eth-yl]-3-methyl-imidazolium dication and a tetra-chlorido-cuprate(II) dianion. The anion adopts a distorted tetra-hedral geometry. Bifurcated interionic N-H⋯Cl hydrogen bonds and several C-H⋯Cl contacts are observed, leading to a layer-like arrangement of the components(More)
Single crystals of cis-[Pt(NO 2) 2 (NH 3) 2 ], were obtained by means of hyper-saturation directly out of a plating electrolyte. The square-planar coordination environment of the divalent Pt II atom is formed by four N atoms belonging to two ammine and two monodentate nitrite ligands. The ligands adopt a cis configuration. The crystal structure contains(More)