Reactions involving fluoride ion. Part 16. Nucleophilic attack on a perfluorotetra-alkylethylene and a synthesis of perfluorotetramethylfuran

Abstract

Reaction of perfluoro-3,4-dimethylhex-3-ene (1) with oxygen nucleophiles gives products arising from attack on (1) as well as products arising from attack on the isomer, perfluoro-3,4-dimethylhex-2-ene (4). A novel cyclisation and defluorination is described for the reaction of (1) with MeOH and Et₃N, giving perfluorotetramethylfuran. Reactions of (1) with difunctional nucleophiles give cyclic products and oxidation of (1) with KMnO₄ in acetone yields a diol. An unusual intramolecular nucleophilic displacement of fluoride from a perfluoroalkyl group is reported.