Syntheses and structures of two benzoyl amides: 2-chloro-4-eth­­oxy-3,5-dimeth­­oxy-N-(3-oxo­cyclo­hex-1-en-1-yl)benzamide and 2-chloro-N-(5,5-di­methyl-3-oxo­cyclo­hex-1-en-1-yl)-4-eth­­oxy-3,5-di­meth­­oxy­benzamide

The first title benzoyl amide, C17H20ClNO5 (3a), crystallizes in the monoclinic space group P21/c with Z = 4 and the second, C19H24ClNO5 (3b), also crystallizes in P21/c with Z = 8 (Z′ = 2), thus there are two independent mol­ecules in the asymmetric unit. In 3a, the phenyl ring makes a dihedral angle of 50.8 (3)° with the amide moiety with the C=O group on the same side of the mol­ecule as the C—Cl group. One meth­oxy group is almost in the plane of the benzene ring, while the eth­oxy and other meth­oxy substituent are arranged on opposite sides of the ring with the eth­oxy group occupying the same side of the ring as the C=O group in the amide moiety. For one of the two mol­ecules in 3b, both the amide and 5,5-dimethyl-3-oxo­cyclo­hex-1-en-1-yl moieties are disordered over two sets of sites with occupancies of 0.551 (2)/0.449 (2) with the major difference between the two conformers being due to the conformation adopted by the cyclo­hex-2-en-1-one ring. The three mol­ecules in 3b (i.e., the undisordered mol­ecule and the two disorder components) differ in the arrangement of the subsituents on the phenyl ring and the conformation adopted by their 5,5-dimethyl-3-oxo­cyclo­hex-1-en-1-yl moieties. In the crystal of 3a, N—H⋯O hydrogen bonds link the mol­ecules into a zigzag chain propagating in the [001] direction. For 3b a combination of C—H⋯O and N—H⋯O inter­molecular inter­actions link the mol­ecules into a zigzag ribbon propagating in the [001] direction.