Fluoro-tris methane

In the pentose series, attack has also been observed to occur mainly from the less-hindered side of the double bond, as in the addition of trifluoro(fluoroxy)methane to di-O-acetyl-D-arabinal. Trifluoromethyl 3,4-di-0-acetyl-2-deoxy-2-fluoro-/3-D-arabinopyranoside and 3,4-di-0-acetyl-2-deoxy-2-fluoro-/J-D-arabinopyranosyl fluoride were obtained,72,74 together with a very small proportion of 3,4-di-0-acetyl-2-deoxy-2-fluoro-a-D-ribopyranosyl fluoride.74 With di-O-acetyl-D-xylal, however, the lyxose derivatives were mainly obtained.72,73 The suggestion has been made73 that the greater conformational mobility of pentopyranoses results in a preponderance of the C d) conformer of the D-lyxose derivatives,72,73 such that F-l and CFsO-l are axially disposed. For further reactions of unsaturated carbohydrates with tri-fluoro(fluoroxy)methane, see Section 11,9. 

Methane Fluoro-tris-[4-nitro-pheriyl]- ElOb,. 113 (OH -> F)... 

In trichlorofluoromethane at low temperatures, trifluoro(fluoro-oxy)-methane (FOCF3) added to the double bond of tri-O-acetyl-D-glucal to give the trifluoromethyl 2-deoxy-2-fluoroglycosides formed by direct, cis addition, together with the two corresponding 2-deoxy-2-... 

The reaction of the carbanion derived from diethyl methylphosphonate with perhalogenated aromatics may result in substitution of halide to yield perhaloaryl(hetaryl)methylphosphonates, which can be converted into tris- or bis-(perhaloaryl)methanes. Displacement of fluoride ion has been reported in the reaction of dimethoxycarbene with l-fluoro-2,4-dinitrobenzene and with hexafluorobenzene. The hydrodehalogenation of halogenated aryl ketones may be facilitated using hydrogen over a Pt/C catalyst. " ... 

Freon—12 or "F-12 . See Dichlorodi-fluoromethane in Vol 5 of Encycl, p D1209-L "Freon—13 , " F—13 ot Monocblorotriffaro-methane. See Chloro tri fluoro me thane in this... 

Xenon difluoride reacts also with some halosubstituted alkanes18,19 at room temperature in chloroform, carbon tetrachloride, dichloromethane or bromoform, and depending on the nature of the solvent used chloro or bromo derivatives are isolated with imidazo-(l,2-fr)-pyridazine18. Carbon tetrachloride reacts with xenon difluoride at 180°C, while room-temperature transformations are achieved when various catalysts [antimony trifluoride, tantalum(V) fluoride or silica dioxide] are used, whose structure also influences the product distribution20. Tris(fluorosulfonyl)methane gives a fluoro-substi-tuted product in its reaction with xenon difluoride in difluorodichloromethane21. 

Experiments in which introduction of bulky pseudofluorides to try to understand the way they might influence the chemistry of low-valent metals was described in Section 3.6 in respect of rhenium complexes. The same thinking has been applied in the case of osmium and the reaction of cf.v-[Os(CO)4Me2] with on the one hand, HF and on the other, HOTeF5 have resulted in methane elimination and the formation of m-[OsF2(CO)4] and c/.v-[Os(OTeF5)(CO)4Me] respectively [44]. This offers the promise that methane elimination from hydrides will be a useful route into other low-valent fluoro derivatives. 

Amino) (alkyl) (fluoro)[bis(trimethylsilyl)methyl]silanes [365] have been obtained by allowing the lithiated tris(trimethylsilyl)methane to react first with trifluoroorga-nosilane and then with lithium bromide. 

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