Abstract Aminoethers, ROC 2 H 4 NCH2CH2OCH2CH 2 (R= C 6 H 5, C 6 F 5, C 2 H 5), C 6 F 5 OC 2 H 4 N [CH 2] 5, were electrofluorinated in anhydrous hydrogen fluoride, the corresponding saturated perfluoroaminoethers being the largest individual substances in each case. One of them, F-[4-(2-cyclohexyloxyethyl) morpholine], has promising properties as a blood substitute.