Crystal structure of 5-[4-(diethylamino)benzylidene]-2,2-dimethyl-1,3-dioxane-4,6-dione

The title compound, C17H21NO4, consists of substituted Meldrum's acid with a [4-(diethylamino)phenyl]methylidene fragment attached to the fifth position. The heterocycle assumes a distorted boat conformation. The planar part of heterocycle is almost coplanar with the benzene ring due to the presence of a long conjugated system in the molecule. This leads to the formation of C—H...O-type intramolecular contacts. As a result of the absence of hydrogen-bond donors in the structure, the crystal packing is controlled by van der Waals forces and weak C—H...O interactions, which associate the molecules into inversion dimers