The title compound, C15H19ClO3, is bent with a dihedral angle of 72.02 (9)° between the mean planes of the benzene ring and a group encompassing the ester functionality (O=C—O—C). In the crystal, mol­ecules related by inversion symmetry are connected by weak C—H⋯O inter­actions into infinite chains. These inter­actions involve H atoms from a methyl group of the dimethyl residue and the O atoms of the ketone on one side of a mol­ecule; on the other side there are inter­actions between H atoms of the benzene ring and the carbonyl O atoms of the ester functionality. There are no directional inter­actions between the chains.

The title compound, C15H19NO5, is bent with a dihedral angle of 61.8 (2)° between the mean planes of the benzene ring and a group encompassing the ester functionality (O=C—O—C). The dihedral angle of 0.8 (2)° between the mean planes of the nitro group and the benzene ring indicates near coplanarity. In the crystal, each mol­ecule is linked to four adjacent mol­ecules by weak C—H⋯O hydrogen-bonding inter­actions. Both benzene H atoms ortho to the ketone O atom form C—H⋯O hydrogen bonds with the keto O atoms of two neighboring mol­ecules (of the keto and ester groups, respectively), and the two other inter­actions involve the H atoms from a methyl group of the dimethyl residue, displaying C—H⋯O inter­actions with the O atoms of the nitro groups. These four inter­actions for each mol­ecule lead to the formation of two-dimensional sheets with a hydro­philic inter­ior, held together by weak hydrogen-bonded inter­actions, and a hydro­phobic exterior composed of protruding methyl groups which interst­ack with the methyl groups in adjacent sheets.