title: Crystal structure of 4-(6-bromo-4-oxo-4H-chromen-3-yl)-2-methyl-amino-3-nitro-pyrano[3,2-c]chromen-5(4H)-one chloro-form monosolvate.
abstract: In the title compound, C22H13BrN2O7·CHCl3, the pyran ring adopts a shallow sofa conformation with the C atom bearing the bromo-chromene system as the flap [deviation = 0.291 (3) Å]. The dihedral angle between the pyran fused-ring system (all atoms; r.m.s. deviation = 0.032 Å) and the bromo-chromene ring system (r.m.s. deviation = 0.027 Å) is 87.56 (9)°. An intra-molecular N-H⋯O hydrogen bond closes an S(6) ring. The Cl atoms of the solvent mol-ecule are disordered over two sets of sites in a 0.515 (6):0.485 (6) ratio. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R 2 (2)(12) loops. The packing also features C-H⋯O and very weak π-π [centroid-centroid separation = 3.960 (2) Å] inter-actions, which link the dimers into a three-dimensional network.
authors.affiliation: Department of Physics, Presidency College (Autonomous), Chennai 600 005, India.
authors.forename: Rajamani
authors.initials: R
authors.lastname: Raja
authors.affiliation: Organic Chemistry Division, CSIR Central Leather Research Institute, Chennai 600 020, India.
authors.forename: Subramani
authors.initials: S
authors.lastname: Kandhasamy
authors.affiliation: Organic Chemistry Division, CSIR Central Leather Research Institute, Chennai 600 020, India.
authors.forename: Paramasivam T
authors.initials: PT
authors.lastname: Perumal
authors.affiliation: Department of Physics, Presidency College (Autonomous), Chennai 600 005, India.
authors.forename: A
authors.initials: A
authors.lastname: SubbiahPandi
keywords: chromenone; crystal structure; hydrogen bonding