Search

Seven methyl and/or ethyl esters of carboxylic acids (CH 2 CH 2 C(O)OEt, CH 2 CH 2 CH 2 C(O)OMe, CH 2 CH 2 CH 2 C(O)OEt, CH(C 2 H 5 )C(O)OMe, CH( n -C 3 H 7 )C(O)OMe, CH 2 CH 2 CH 2 CH 2 C(O)OEt and CH 2 CH 2 CH 2 CH 2 CH 2 C(O)OEt) having a morpholino group were subjected to electrochemical fluorination (ECF). On ECF, the corresponding perfluoroacid fluorides bearing a perfluoromorpholino group were obtained in fair to good yields. Yields of the targeted perfluoromorpholino-containing perfluoroacid fluorides were influenced by the α-bond cleavage of the carboxylic acid and also by the kind of alkyl group of the carboxylic acid (the latter offering the possibility of cyclization side reactions). Perfluorooxolanes were formed as a major cyclization by-product from the ECF of morpholino-substituted carboxylic acids when the chain length of the alkyl group of the carboxylic acids had a carbon number of three or more and the structure of the alkyl group was branched in such a way as to allow cyclization. Perfluorodioxolanes were obtained in only small yields as the specific cyclization products when the ethyl esters of carboxylic acids were subjected to ECF. Spectroscopic data, as well as physicochemical properties, are described for the new perfluoroheterocyclic compounds with a perfluoromorpholino group that were produced.

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.

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.

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.

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.