Crystal structure, Hirshfeld surface analysis and interaction energy and DFT studies of 10-allyl-pyrrolo[2,1-c][1,4]benzodiazepine-5,11-dione

Abstract

The title compound, C15H16N2O2, consists of pyrrole and benzodiazepine units linked to an allyl moiety, where the pyrrole and diazepine rings adopt half-chair and boat conformations, respectively. In the crystal, weak C—HBnz···ODiazp (Bnz = benzene and Diazp = diazepine) hydrogen bonds link the molecules into infinite chains along the c-axis direction with the corrugated stacks along the a-axis direction. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H ··· H (60.6%), H ··· C/C ··· H (18.0%) and H ··· O/O ··· H (17.4%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. Computational chemistry indicates that in the crystal, C—H···O hydrogen bond energy is 32.9 (for C—HBnz···ODiazp) kJ mol-1. Density functional theory (DFT) optimized structures at the B3LYP/ 6–311G(d,p) level are compared with the experimentally determined molecular structure in the solid state. The HOMO—LUMO behaviour was elucidated to determine the energy gap..