Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

The reaction of diethylamine with methyl trifluoropropenoate (I), methyl 2-chloro-3,3-difluoropropenoate (II), methyl 3,3-difluoropropenoate III) and methyl 3-chloro-2,3-difluoropropenoate (IV) affords halogenated 3-diethylaminopropenoates V-VII via the vinylic substitution of fluorine or chlorine atoms. When hydrolyzed the latter give methyl N,N-diethylcarbamoylacetates X-XII. On addition of 1-butanol and 2,2,3,3-tetrafluoropropanol to aminopropenoates V-VII fluorinated 3-alkoxy-3-diethylaminopropenoates XIII-XVI were prepared which when hydrolyzed eliminate the diethylamino group under formation of alkyl methylpropanedioates XX to XXIII. Heating of aminoethers XIII-XVI at 150 °C gives 1-fluorobutane or 1,1,2,2,3-pentafluoropropane, respectively. These fluoro derivatives are also formed on heating of the mentioned alcohols with 3-diethylaminopropenoates V-VII. During the thermal decomposition of methyl 2-chloro-3-diethylamino-3-fluoro-3-(2,2,3,3-tetrafluoropropoxy)propanoate (XV) 3-chloro-1,1,2,2-tetrafluoropropane was formed as a by-product. The substitution of the hydroxyl group with fluorine is discussed from the point of view of preparative application.