Highly fluorinated heterocycles. Part III. The preparation and reactions of some polyfluorofurans

Abstract

Tetrafluorofuran, both trifluorofurans, and 2,3- and 3,4-difluorofuran have been prepared by dehydrofluorination of partially fluorinated oxolans; 2,5-difluorofuran has been made similarly from 2,2,5-trifluoro-3-oxolen. All the furans polymerised rapidly and spontaneously; the polymers from tetrafluorofuran and 2,5-difluorofuran were stable white solids and those from the rest were unstable liquids or solids. Bromine and chlorine added 2,5 to tetrafluorofuran and to 2,3,4-trifluorofuran; the latter also underwent 2,5-addition of acetyl nitrate. 2,3,4-Trifluorofuran can be lithiated and thence carbonated to 3,4,5-trifluorofuroic acid.