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Cis-2,6-dimethylmorpholine and its derivatives having an ester group were subjected to electrochemical fluorination. The electrochemical fluorination of cis-2,6-dimethylmorpholine afforded only a small quantity of F-(N-fluoro-2,6-dimethyl-morpholine), whereas the N-(methoxycarbonylalkyl)-substituted cis-2,6-dimethyl-morpholines gave the corresponding F-acid fluorides in fair yields. Cis-and trans-isomerization on two methyl substituents of the morpholine ring occurred through electrochemical fluorination of pure cis-2,6-dimethylmorpholine to give a 1:0.25–0.5 mixture of cis- and trans-isomers having a F-2,6-dimethylmorpholino-moiety. The formation of a seven-membered ring expanded product was confirmed as a by-product in the fluorination of methyl cis-2,6-dimethylmorpholino-acetate. Spectroscopic data as well as physical properties of new nitrogen-containing F-carboxylic acids are presented.

Polyfluorinated tertiary amines were synthesized by the reactions of primary alkyl triflates (RFCH2OSO2CF3, RF = CF3, C2F with the morpholide anion, preformed from perfluoro(5,6-dihydro-2H-1,4-oxazine) on treatment with potassium fluoride (in tetraglyme). In the case of (CF3)2CHOSO2CF3, polyfluoroalkoxylated oxazine was obtained by replacement of the imidoyl fluorine. A similar imidoyl fluorine substitution reaction occurred in the treatment of perfluoro(5,6-dihydro-2H-1,4-oxazine) with polyfluoroalkylsiloxanes regardless of alkyl group variation.

Series of amino alcohols including 2-( N,N -dialkylamino)ethanols, 3-( N,N -dimethylamino)propanol and 4-( N,N -dimethylamino)butanol were subjected to electrochemical fluorination. In the case of 2-( N,N -dialkylamino)ethanols, the F -(2- N,N -dialkylamino)acetyl fluorides were obtained in fair to good yields. Yields of each target compound were strongly dependent on the kind of the dialkylamino group. Cyclic amines having an N -(2-hydroxylethyl) group afforded the corresponding F -[ N -( c -alkylamino)-substituted acetyl fluorides]. Their yields were generally better than those of acyclic analogs. Several 2-( N,N -dialkylamino)ethanols and 3-( N,N -dimethylamino)propanol were converted into the corresponding trimethylsilylethers, aminoalkyl methyl carbonates and bis-aminoalkyl carbonate, respectively, and they were subjected to fluorination for a comparison of the yield with that obtained from that of the parent aminoalcohol.