B. Lorenz

Nitridokomplexe des Technetium(V)

Folgende Komplexe des funfuertigen Tichnitiums wurden dargestellt und charakterisiert TcNCl2[P(C6H5)3]2 (A) Tc NCl2 (PR2C6H5)3 [R = CH3 (B) bzw. C2H5 (C)] TcN[(C2H5)2NCS2]2 (D) Die Darstellung von (A) erfolgt anlog der entsprechenden Rheniumkomplexes; (B), (C) und (D) wurden durch Reaktron von (A) mit uberschunssigem PR2C6H5 bzw. Na(C2H5)2NCS2 durch Substitutionsreaktionen orhalten. Die genannten Komplexe sind bomerkenswert hydrolysebestandig. Here IR- und 1H-NMR-Spektren warden diskutiert

HTc(N2)(dppe)2 as starting material for mixed-ligand complexes of technetium(I)

Abstract In the complex HTc(N2)(dppe)2 the nitrogen ligand is most labile and can be exchanged under mild conditions for CO, isonitriles and phosphites (L1), yielding neutral hydridocomplexes of Tc(1) HTcL1(dppe)2. HTc(CO)(dppe)2 is also formed from the title compound by CO abstraction from methanol. In the complexes HTcL1(dppe)2 the hydrido ligand can be exchanged for acetonitrile (L2), yielding cationic mixed-ligand complexes of Tc(I) TcL1L2(dppe)2+, which are isolated as hexafluorophosphates.

IR-spektroskopische und mechanistische Untersuchungen an Technetiumkomplexen unter Einsatz von 15N

The formation of Technetium nitrido- and thionitrosyl-complexes was investigated by means of 15N labelled compounds. The course of the reaction is rather different with the elements technetium and rhenium in spite of quite analogous starting materials and products. A new feasible synthesis of nitridotechnetium (V) complexes was found from complexes of Te(III) and azide. By 15N-substitution an unambiguous assignment of characteristic infrared bonds in the complexes was achieved.

Reaktion von Pyridin-2-Carbonsäure Mit Tetrabutylammonium-Tetrachloro-Nitridotechnetat(VI) Sowie Tetrabutylammonium-Tetrachlorooxotechnetat (V)

Abstract The reaction of 2-pyridine carboxylic acid (Hpic) with (n-Bu4N)[TcNCl4] and (n-Bu4N)[TcOCl4] in ethanol and methanol, respectively, yields the dinuclear μ-oxo complex [(pic)2NTc-O-TcN(pic)(Hpic)Cl] and the monomeric complex [TcO(pic)2Cl]. Visible and infrared spectroscopy, ESR, 1H-NMR and 99Tc-NMR have been used to characterize the new compounds. The most important field of application for the new compounds synthesized is radiodiagnostics.

Bestimmung der Empfindlichkeit bei Tc-99-NMR-Messungen an einem 250-MHz-Spektrometer

By means of different concentrations the signal-to-noise ratios of Tc-99-NMR spectra were determined applying well measurable Tc-samples [tetrabutylammoniwn pertechnetate, TBA (TcO4)J and a 250 MHz-spectrometer. The signal-to-noise ratios of the spectra were determined by using the integrated routines of the firms software and accumulating different number of scans. By fittings of data of the signal-to-noise ratio dependence and by extrapolation the minimum Tc-concentralion could be empirically found out. Applying a duration of measurements of 12 hours about 10−7 molar concentrations can be determined.