Synthesis, crystal structure and computational analysis of 2,7-bis-(4-chloro-phen-yl)-3,3-dimethyl-1,4-diazepan-5-one.

In the title compound, C19H20Cl2N2O, the seven-membered 1,4-diazepane ring adopts a chair conformation while the 4-chloro-phenyl substituents adopt equatorial orientations. The chloro-phenyl ring at position 7 is disordered over two positions [site occupancies 0.480 (16):0.520 (16)]. The dihedral angle between the two benzene rings is 63.0 (4)°. The methyl groups at position 3 have an axial and an equatorial orientation. The compound exists as a dimer exhibiting inter-molecular N-H⋯O hydrogen bonding with R 2 2(8) graph-set motifs. The crystal structure is further stabilized by C-H⋯O hydrogen bonds together with two C-Cl⋯π (ring) inter-actions. The geometry was optimized by DFT using the B3LYP/6-31 G(d,p) level basis set. In addition, the HOMO and LUMO energies, chemical reactivity parameters and mol-ecular electrostatic potential were calculated at the same level of theory. Hirshfeld surface analysis indicated that the most important contributions to the crystal packing are from H⋯H (45.6%), Cl⋯H/H⋯Cl (23.8%), H⋯C/C⋯H (12.6%), H⋯O/O⋯H (8.7%) and C⋯Cl/Cl⋯C (7.1%) inter-actions. Analysis of the inter-action energies showed that the dispersion energy is greater than the electrostatic energy. A crystal void volume of 237.16 Å3 is observed. A mol-ecular docking study with the human oestrogen receptor 3ERT protein revealed good docking with a score of -8.9 kcal mol-1.