Synthesis of perfluorobicyclic ethers [2]. The electrochemical fluorination of α-cyclohexenyl-substituted carboxylic acid derivatives

The electrochemical fluorination of α-cyclohexenyl-substituted carboxylic esters

; R′CH₃, C₂H₅, C₃H₇)] afforded both perfluoro(9-alkyl-7-oxa-bicyclo4.3.0]nonane)s and perfluoro(8-alkoxy-9-alkyl-7-oxabicyclo4.3.0]nonane)s in fairly good yields. As the driving force for the ring-closure in this fluorination, a mechanism which involves a resonance stabilized intermediate radical is proposed. Perfluoro(8-chloro-8-methoxy-9-ethyl-7-oxabicyclo4.3.0]nonane) and perfluoro(8,8-dichloro-9-ethyl-7-oxabicyclo4.3.0]nonane) were obtained by the controlled chlorination of perfluoro(8-methoxy-9-ethyl-7-oxabicyclo4.3.0]nonane) with anhydrous aluminum chloride in low yields. Some new fused perfluorobicyclic ethers and a perfluoroacid fluoride obtained in this experiment have been characterized by infrared, mass and ¹⁹F nmr spectra and elemental analysis.