Platinum, xenon fluoride reactions

Fluorination with elemental fluorine diluted 1 20 with nitrogen was used to prepare pentafluorophenyl tellurium trifluoride from bis[pentafluorophenyl] ditellurium at — 60° with fluorotrichloromethane as the reaction medium. The yield in this reaction was 80% 4-Methoxyphenyl tellurium trifluoride was obtained by electrochemical oxidation of the diaryl ditellurium in 0.5 M hydrofluoric acid at platinum electrodes2. Bisfpentafluoroethyl] ditellurium and chlorine fluoride (1 6) reacted at — 78° to give pentafluoroethyl tellurium trifluoride, a white solid melting at 95°3. The same compound was obtained with xenon difluoride as the fluorinating agent and melted at 143°4. 

The departure from the 1 1 reaction stoichiometry in the xenon-rhodium hexafluoride system is less than for the platinum system. This is surprising in view of the greater instability and chemical reactivity of the rhodium fluoride. Ruthenium hexafluoride, which is less reactive than rhodium hexafluoride, has been reported [7] to react non-stoichiometrically with xenon. Perhaps the use of small quantities of rhodium fluoride favored the 1 1 addition. There is as yet no evidence for the oxidation state of rhodium in the adduct, although the formulation Xe -1- [RhFe] would, as in the corresponding platinum case, appear to be energetically more favorable than Xe +[RhF6] . 

A platinum (II)-Csp3 bond was efficiently fluorinated stereo-retentively by NFSi, although xenon difluoride was preferred in this reaction, through a putative Pt(IV)-fluoride that gives the C-F reductive elimination preferentially over competing p-H elimination (eq 41). ... 

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