3:;10049-03-3Relevant articles and documents
Synthesis and properties of NF4+ClO4- and NF4+HF2-·nHF and some reaction chemistry of NF4+ salts
Christe, Karl O.,Wilson, William W.,Wilson, Richard D.
, p. 1494 - 1498 (2008/10/08)
The possibility of synthesizing NF4+XO4- (X = Cl, Br, I) salts by metathesis between NF4SbF6 and CsXO4 in anhydrous HF solution at -78°C was studied. Of these NF4XO4 salts, NF4ClO4 was isolated and characterized by vibrational and 19F NMR spectroscopy. It is an unstable white solid decomposing at 25°C to give NF3 and FOClO3 in high yield. The NF4BrO4 salt is of marginal stability in HF solution and decomposes to NF3, O2, and FBrO2. Attempts to isolate NF4BrO4 as a solid resulted in explosions. The NF4IO4 salt could not be prepared due to the facile fluorination of IO4- to IF4O2- by either HF or BrF5. Attempts to prepare NF4+XF4O- (X = Cl, Br) salts by metathesis between NF4SbF6 and CsXF4O in BrF5 solution at 25°C were unsuccessful; with BrF4O-, fluoride abstraction occurred, resulting in the formation of NF3, F2, and BrF3O, whereas CsClF4O underwent a displacement reaction with BrF5 to give CsBrF6 and ClF3O. The metathetical synthesis of NF4NO3 could not be studied in HF due to the reaction of NO3- with HF to give NO2+, H2O, and HF2-. The metathesis between NF4SbF6 and CsF in HF at -78°C did not produce NF4+F- but produced an unstable white solid of the composition NF4+HF2-·nHF. The composition, thermal stability, spectroscopic properties, and decomposition products of this solid were studied. The NF4+HF2- salt is stable in HF solution at 25°C, and the synthetic usefulness of these solutions for the synthesis of other NF4+ salts is briefly discussed. Attempts to prepare NCl4+ and NCl2O+ salts by F-Cl exchange between BCl3 and NF4+ and NF2O+ were unsuccessful.
