US Patent 7601864 Method for synthesizing 4,4-dihalogen-2-(dialkylamino)methylene-3-oxy-alkylbutyrate and derivatives thereof

A method for synthesizing 4,4-dihalogen-2-(dialkylamino)methylene-3-oxy-alkylbutyrate and its derivatives has acts of: (a) providing N,N-dialkylamino-alkyl-acrylate in a reaction vessel; (b) adding organic alkali, organic solvent and multiple molecular sieves into the reaction vessel; (c) mixing N,N-dialkylamino-alkyl-acrylate, the organic alkali, the organic solvent and the molecular sieves; and (d) adding 2,2-dihalogen-acetyl-chloride into the reaction vessel and allowing a synthetic reaction of 2,2-dihalogen-acetyl-chloride and N,N-dialkylamino-alkyl-acrylate to obtain 4,4-dihalogen-2-(dialkylamino)methylene-3-oxy-alkylbutyrate. The molecular sieves are able to remove water efficiently to prevent materials in the reaction vessel from undergoing side reactions or changing chemical properties. Furthermore, the molecular sieves are able to adsorb chloride to avoid polymerization reactions for improved yield.