Transformation of chlorofluoroethyldiethylamines to N,N-diethyldifluoroacetamide

Hydrolysis of 2-chloro-1,1,2-trifluoroethyldiethylamine (I) and 2,2-dichloro-1,1-difluoroethyl-diethylamine (II) in the presence of triethylamine afforded N,N-diethylchlorofluoroacetamide (VII) and N.N-diethyldichloroacetamide (VIII), respectively. Triethylamine hydrofluoride, arising in the reaction, was used for fluorination and transformation of the amides VII and VIII to N,N-diethyldifluoroacetamide (VI). The C-Cl bond of the CHClF group in VII proved to be more reactive in nucleophilic substitution with fluoride ion than the corresponding bond in the CHCl2 group of VIII.