New High Oxidation State Fluorides and Oxide Fluorides of Technetium and Iridium
Final Report Abstract
During the supported research time in Canada, two main projects were initiated and almost finished. One project was aimed at the new iridium oxidation state, +VII. This aim was, in principal, attained because the target species [IrF6]+ was prepared and studied in the gas-phase by mass spectrometry. This already represents the discovery of a new oxidation state of iridium. Nevertheless, attempts to prepare the corresponding ion-pair complex in bulk quantities have thus far failed. This part of the project is still ongoing in cooperation with the Schrobilgen group at McMaster University. We are quite optimistic that the global aim: the preparation of IrF7 via the precursor [IrF6]+cation is only a matter of time. The second project which was inspired by the prior work, has recently been completed. The preparation of a new iridium oxidation state, +VIII, as IrO4 under cryogenic conditions in neon, argon and krypton matrices was successful. Investigations of Bora-Haber cycles have also shown that this new species is only stable under low-temperature matrix conditions and is therefore not observable in the bulk solid under room temperature conditions where OSO4 is stable. Nevertheless, the research supported by the DFG has lead into the discovery of two new oxidation states in the periodic table, namely Ir +V11 and +VIII, and has inspired a large number of other interesting and promising projects. Furthermore it was a very interesting and fruitful instruction into the preparative fluorine chemistry.
