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This paper is concerned with the reactions of (Rf)3PF2 and (Rf)3PO with N-, 0-, C-nucleophiles and fluoride ion. Either the replacement of one or two perfluoroalkyl radicals by different functional groups or the addition of reagent to electrophilic phosphorus occurs. These phosphinic oxides and phosphoranes readily add fluoride-ion with the expansion of phosphorus coordination: the former produces phosphoranes OP a new type (Rf)3P(F)O−Cs+, while the latter stable substituted fluorophosphates of general formula M +[(Rf)3 PF3]−. Based on these salts it was possible to synthesize aryldiazonium tris(perfluoroalkyl)trifluorophosphates, whose thermal decomposition leads to the formation of substituted fluorobenzenes with high yields. The reaction is a convenient modification of the Shieman methd. The approaches of the synthesis of phosphoranes containing simultaneously both perfluoroalkyl groups and nonfluorin-ated radicals are developed due to the reactions of tris-(perf luoroalkyl)dif luorophosphoran... |
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