The preparation and identification of N-fluoro-N′-trifluoromethyldiazine-N′-oxide

Structure of a Fluorinated Azoxy Compound: Fluoro(trifluoromethyl)-diazene-2-oxide, CF3N(O)NF

“…The azoxy compound investigated in this study exists as the CF 3 N(O)NF isomer, although quantum chemical calculations predict the CF 3 NN(O)F isomer to be lower in energy by about 12 kcal/mol. This result which is supported by various spectral observations, including mass, infrared, and nuclear magnetic resonance spectra, can be rationalized by the synthetic route by which it was prepared (see Experimental Section). The use of the reactant CF 3 NO, in which NO is already bonded to the CF 3 group, leads to the formation of the CF 3 N(O)NF isomer in the first step.…”

“…Final purification was obtained by gas chromatography. The compound obtained with this method, which is a slight modification of that reported in ref , was identified as the CF 3 N(O)NF isomer on the basis of IR, 19 F NMR, and mass spectrometric data …”

“…CF 3 N(O)NF is, besides c -C 4 F 7 N(O)NF, the only azoxy compound known in which a halogen atom is bonded directly to one of the nitrogen atoms. Its first synthesis and a short characterization by vibrational and 19 F NMR spectroscopy and mass spectrometry have been reported in 1962 . Several resonance structures have been proposed to describe the bonding in azoxy compounds (Chart ), ionic structures Ia and Ib, a diradical structure II, and a hypervalent structure III. , According to a quantitative valence bond (VB) analysis of the parent compound HN(O)NH, the hypervalent structure III possesses the strongest contribution (50%), and the two ionic structures contribute about 20% each .…”

Derivatives of Nitrogen Fluorides

“…There are several examples of compounds which contain the -N (-*0)=NF group. All known derivatives are prepared by essentially the same reaction, the interaction of tetrafluorohydrazine (or difluoramine in pyridine) with a nitroso compound (47,136). The ultraviolet and F19 nmr spectral properties of CFsN(-*O)=NF are more consistent with the assignment of the N'-fluorodiimide N-oxide structure to the product than one of the other possibilities, such as CF8ON=NF, CF3NFN=0, or CF3N=NOF (47).…”