Über Tellurhalogenide des Kupfers mit hoher Ionen-Teilleitfähigkeit Die Kristallstruktur von CuTeJ

Telluride Halides of Copper with High Ionic Partial Conductivity. The Crystal Structure of CuTeI Copper telluride iodide, CuTeI, which has a high copper(I) ionic partial conductivity, could be obtained as crystals and the structure determined (359 hkl, R = 0.031). The space group is I4₁/amd with the lattice constants a = 17.170, c = 4.876 Å, and Z = 16. Characteristic for the structure are the helicoidal arrangements of the tellurium atoms, symmetry related by fourfold screwaxes (4₁) and the statistical population of the Cu sites. The latter is a hint for a copper ionic conductivity.     

Eine mikrophotometrische Kobaltbestimmung mit Antipyrin-4-dithiocarbons?ure

Ohne Zusammenfassung     

Eine Boswelliasäure aus Weihrauch

3‐O‐Acetyl‐11‐keto‐β‐boswelliasäure was extracted from pulverized frankincense and purified by HPLC. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the ¹³C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009).     

Herstellung und 29Si-NMR-Untersuchung von Polymeren mit definierten Kieselsäurebaueinheiten

Preparation and ²⁹Si NMR Spectroscopic Investigation of Polymers with Definite Silicic Acid Units Three polymers were synthesized by additive reaction of the cage-like double fourring (D4R) silicic acid derivatives [(CH₃)₂HSi]₈Si₈O₂₀ and [CH₂?CH(CH₃)₂Si]₈Si₈O₂₀ resp., with the unsaturated diviyltetramethyldisiloxane or the multiple functional tetramethylcyclotetrasiloxane and polymethylhydrogensiloxane in a molar ratio of functional groups 1:1. By means of ²⁹Si solid state NMR spectroscopy was shown that the in organic solvents insoluble polymers are built up by D4R silicic acid units, which are connected by chain-like or cyclic siloxane bridges. With increasing functional groups of the reactants the sterical hindrance of the reaction of D4R derivates grows. The polymers show small surfaces of 1 to 8 m²/g.     

Cyclische Kieselsäurederivate

Cyclic Silicic Acid Derivatives By reaction of SiCl₄ with oxygen at elevated temperatures a number of chlorsiloxanes consisting of more or less fused rings can be prepared of which those components of low molecular weight can be separated by combining distillation and crystallization. Methyl and ethyl esters of silicic acids are obtained by reaction with methyl or ethyl nitrite, resp. The compounds are characterized by silicon n.m.r. and mass spectroscopy.     

Eine gasometrische Bestimmung von Alkylaziden mit Natriumjodid-Trichloressigs?ure

Ohne Zusammenfassung