Dimethyl 4-(4-formylphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate

The title compound, C18H19NO5, is a product of the Hantzsch reaction of p-phthalaldehyde, methyl acetoacetate, and ammonium acetate. The 1,4-dihydropyridine ring of the molecule adopts a flattened boat conformation. The benzene ring is almost perpendicular to the 1,4-dihydropyridine ring; the plane through the six C atoms of the benzene ring and the plane through the four C atoms that form the base of the boat-shaped 1,4-dihydropyridine ring (excluding the ring N atom and the opposite ring C atom) make a dihedral angle of 87.60 (3)°. Intermolecular N—H...O hydrogen bonds result in the formation of extended chains along the a axis.