Abstract: β-Diketones (acetylacetone, propionylacetone and benzoylacetone) were treated with acrylonitrile in the presence of aqueous potassium hydroxide giving monocyanoethylated β-diketones (Ⅰ)-(Ⅲ), which by heating with HCl were isomerized to the corresponding3,4-dihydro-2-(lH) pyrid-ones(Ⅳ)-(Ⅵ). (Ⅰ)-(Ⅲ) and (Ⅳ)-(Ⅵ) were hydrolyzed to the ketoacids (Ⅶ)-(Ⅸ). 2,4-Dinitrophenylhydrazones(Ⅹ)-(Ⅻ) were prepared from(Ⅳ) -(Ⅵ). Compounds (Ⅱ), (Ⅲ), (Ⅴ), (Ⅵ)and(Ⅷ)-(Ⅶ) were reported for the first time.