RuF6─An Oxidizer Stronger than PtF6: The Formation of Coordinatively Saturated Cations with RuF6.

We report the oxidative fluorination of NF3, ClF5, and BrF5 with RuF6 and the formation of compounds containing the coordinatively saturated cations [NF4]+, [ClF6]+, and [BrF6]+. As RuF6 is a one electron oxidizing agent, two equivalents of RuF6 should be required for complete oxidation of NF3, ClF5, and BrF5. However, oxidation of NF3 requires a 3:1 ratio as [NF4][Ru3F16] and F2 are formed, whereas ClF5 is oxidized with the expected 2:1 ratio forming [ClF6][Ru2F11] but no F2. Both compounds were characterized by X-ray diffraction and vibrational spectroscopy. In contrast to the reactions above, the oxidation of BrF5 leads only to small amounts of [BrF6]+ cations in solution, which rapidly decompose to BrF5 and F2. Therefore, RuF6 is capable of oxidizing BrF5 in contrast to PtF6, highlighting its higher oxidizing strength under these conditions. In addition, practical aspects of handling RuF6, such as diffusion through perfluorinated polymers, stress cracking and material degradation, are discussed.