3-Phenylisoxazolin-5-one: a redetermination

Crystal structure, Hirshfeld surface analysis and inter-action energy calculation of 4-(furan-2-yl)-2-(6-methyl-2,4-dioxo-pyran-3-yl-idene)-2,3,4,5-tetra-hydro-1H-1,5-benzodiazepine

The title compound {systematic name: (S,E)-3-[4-(furan-2-yl)-2,3,4,5-tetra-hydro-1H-benzo[b][1,4]diazepin-2-yl-idene]-6-methyl-2H-pyran-2,4(3H)-dione}, C19H16N2O4, is constructed from a benzodiazepine ring system linked to furan and pendant di-hydro-pyran rings, where the benzene and furan rings are oriented at a dihedral angle of 48.7 (2)°. The pyran ring is modestly non-planar [largest deviation of 0.029 (4) Å from the least-squares plane] while the tetra-hydro-diazepine ring adopts a boat conformation. The rotational orientation of the pendant di-hydro-pyran ring is partially determined by an intra-molecular N-HDiazp⋯ODhydp (Diazp = diazepine and Dhydp = di-hydro-pyran) hydrogen bond. In the crystal, layers of mol-ecules parallel to the bc plane are formed by N-HDiazp⋯ODhydp hydrogen bonds and slipped π-π stacking inter-actions. The layers are connected by additional slipped π-π stacking inter-actions. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (46.8%), H⋯O/O⋯H (23.5%) and H⋯C/C⋯H (15.8%) inter-actions, indicating that van der Waals inter-actions are the dominant forces in the crystal packing. Computational chemistry indicates that in the crystal the N-H⋯O hydrogen-bond energy is 57.5 kJ mol-1.