A New Synthesis of Fluorinated Oxetanes

Article abstract of DOI:10.1021/jo00116a030

Polyfluorinated oxetanes are prepared in high yields by an electrophilic <2+2> cycloaddition reaction between hexafluoroacetone and fluorinated ethylenes that is catalyzed by an anhydrous aluminum chlorofluoride Lewis acid.The reaction is regiospecific with hydrofluoroethylenes CHX=CF2 (X = H, F, Cl, Br), whereas halotrifluoroethylenes CFX=CF2 (X = Cl, Br) give nearly equal amounts of the isomeric oxetanes.Hexafluoropropylene oxide, which rapidly rearranges under the reaction conditions, can be substituted for hexafluoroacetone in this new oxetane synthesis.