Ammonium Pertechnetate in Mixtures of Trifluoromethanesulfonic Acid and Trifluoromethanesulfonic Anhydride
Markus Zegke, Dennis Grödler, Maximilian Roca Jungfer, Alexander Haseloer, Meike Kreuter, Jörg‐M. Neudörfl, Thomas Sittel, Christopher M. James, Jörg Rothe, Marcus Altmaier, Axel Klein, Martin Breugst, Ulrich Abram, Erik Strub, Mathias S. Wickleder
Abstract
Abstract Ammonium pertechnetate reacts in mixtures of trifluoromethanesulfonic anhydride and trifluoromethanesulfonic acid under final formation of ammonium pentakis(trifluoromethanesulfonato)oxidotechnetate(V), (NH 4 ) 2 [TcO(OTf) 5 ]. The reaction proceeds only at exact concentrations and under the exclusion of air and moisture via pertechnetyl trifluoromethanesulfonate, [TcO 3 (OTf)], and intermediate Tc VI species. 99 Tc nuclear magnetic resonance (NMR) has been used to study the Tc VII compound and electron paramagnetic resonance (EPR), 99 Tc NMR and X‐ray absorption near‐edge structure (XANES) experiments indicate the presence of the reduced technetium species. In moist air, (NH 4 ) 2 [TcO(OTf) 5 ] slowly hydrolyses under formation of the tetrameric oxidotechnetate(V) (NH 4 ) 4 [{TcO(TcO 4 ) 4 } 4 ] ⋅10 H 2 O. Single‐crystal X‐ray crystallography was used to determine the solid‐state structures. Additionally, UV/Vis absorption and IR spectra as well as quantum chemical calculations confirm the identity of the species.