title: 7,7-Dimethyl-2-methyl-amino-4-(4-methyl-phenyl)-3-nitro-7,8-di-hydro-4H-chromen-5(6H)-one.
abstract: In the title compound, C19H22N2O4, the six-membered cyclo-hexenone ring of the chromene unit adopts an envelope conformation, with the dimethyl-substituted C atom as the flap, while the pyran ring has a boat conformation. These two mean planes are inclined to one another by 6.65 (13)°·The benzene ring is normal to the 4H-chromene moiety mean plane, making a dihedral angle of 89.18 (5)°. The methyl-amine and nitro groups are slightly twisted from the chromene moiety mean plane, with torsion angles C-N-C-O = 1.70 (18) and O-N-C-C = 0.15 (18)°. The mol-ecular structure is characterized by an intra-molecular N-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked via pairs of weak C-H⋯O hydrogen bonds, forming inversion dimers. These dimers are connected by further C-H⋯O hydrogen bonds, forming sheets lying parallel to (10-1).
authors.affiliation: Sri Ram Engineering College, Chennai 602 024, India.
authors.forename: S Antony
authors.initials: SA
authors.lastname: Inglebert
authors.affiliation: Organic Chemistry Division, CSIR Central Leather Research Institute, Chennai 600 020, India.
authors.forename: Jayabal
authors.initials: J
authors.lastname: Kamalraja
authors.affiliation: Department of Physics, RKM Vivekananda College (Autonomous), Chennai 600 004, India.
authors.forename: K
authors.initials: K
authors.lastname: Sethusankar
authors.affiliation: Organic Chemistry Division, CSIR Central Leather Research Institute, Chennai 600 020, India.
authors.forename: Paramasivam T
authors.initials: PT
authors.lastname: Perumal