The perfluorocyclic ethers as well as the perfluoroalkanoyl fluorides were obtained by the electrochemical fluorination of primary monohydric alcohols and aldehydes containing 4–8 carbon atoms. The five-membered rather than the six-membered perfluorocyclic ethers were formed as the cyclic products. The over-all yields of the perfluorocyclic ethers and the perfluoroalkanoyl fluorides from the alcohols were in the range of 10–20%, and 3–12% ...