Polyfluoroalkyl, derivatives

Polyfluoroalkyl Derivatives of Metalloids and Nonmetals R. E. Banks and R. N. Haszeldine... 

Some syntheses of perfluoroalkyl and polyfluoroalkyl derivatives are shown in Figure 10.49. 

The (a,a,(o-trihydropcrfluoroalkyl)phenyliodonium tetrafluoroborates (115) and (118) reacted with nucleophilic substrates to afford the polyfluoroalkylated derivatives. This is the case of p-chloro-thiophenol, aniline and pyridine. In the reaction with TVJV-dimethylaniline, the -polyfluoroalkyl product (116) was predominant, but nevertheless a small amount of ring-alkylation product (117) was also obtained.224... 

Polyfluoroalkyl iodides react regioselectively with furan to form 2-polyfluoroalkyl derivatives in the presence of catalytic amounts of tetrakis(triphenylphosphine) nickel at 60-80° C. 

For details of the conversion of polyfluoroalkylmercurials into poly-fluoroalkyi(triethylgermyl)mercurials and thence polyfluoroalkyl derivatives of germanium, see p. 202. Intermediates such as MejSi-Hg-CFg-CFa-SiMea encountered during reactions between fluoro-olefins and bisftrimethylsilyl)-meicury are mentioned on p. 201. 

The temperatures quoted are those at which decomposition becomes appreciably rapid. Presumably metal fluorides are also formed in these decompositions but this has not been proven. A reaction which is apparently the reverse of these pyrolyses was mentioned above, namely the addition of platinum-fluorine bonds to tetrafluoroethylene 118). The thermal decomposition of perfluoroalkyl and polyfluoroalkyl derivatives of main group elements such as boron, silicon, or tin was mentioned in earlier sections of this chapter. Transfer of fluorine atoms from the side chains on heating was also a characteristic property. However, it is interesting to compare the reaction (97),... 

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