Novel rearrangement reactions leading to the formation of 2-piperidinyl-tetrahydroquinolinones were observed to occur in reactions of enaminonitrile with the 1,3-cyclohexanedione derivatives. In contrast, 2-phenyl-3-(piperidin-1-yl)acrylonitrile was observed to react with 5,5-dimethyl-1,3-cyclohexanedione to yield 7,7-dimethyl-3-phenyl-7,8-dihydroquinoline-2,5(1H,6H)-dione. While not participating in reaction with 5,5-dimethyl-1,3-cyclohexanedione, 2-benzoyl-3-(dimethylamino)acrylonitrile reacted with 3-oxo-3-phenylpropanenitrile to yield 2-benzoyl-4-[hydroxy(phenyl)-methylene]pent-2-enedinitrile and 5-benzoyl-6-hydroxy-2-phenylnicotinonitrile. The structure of 2-benzoyl-4-[hydroxy(phenyl)methylene]pent-2-enedinitrile along with other substances prepared in this effort were determined by X-ray crystallographic analysis.