Crystal structures of (12E)-12-(4-benzyl-idene)-7,7,16-trimethyl-3-(4-methyl-phen-yl)-1-oxa-16-aza-tetra-cyclo-[11.2.1.02,11.04,9]hexa-deca-2(11),4(9)-dien-5-one and (12E)-12-(4-bromo-benzyl-idene)-73-(4-bromo-phen-yl)-,7,16-trimethyl-10-oxa-16-aza-tetra-cyclo-[11.2.1.02,11.04,9]hexa-deca-2(11),4(9)-dien-5-one.

The title compounds, C32H35NO2, (I), and C30H29Br2NO2, (II), differ by the presence of a bromine atom instead of a methyl atom in the para position of two benzene rings of compound (II). The two compounds have a structural overlap r.m.s. deviation of 0.27 Å. The pyran and seven-membered cyclo-heptene rings in both structures adopt boat and boat-sofa conformations, respectively. Intra- and inter-molecular C-H⋯O hydrogen bonds are responsible for the consolidation of the crystal packing of both mol-ecules. In addition to this, weak C-H⋯π inter-actions are also observed. The inter-molecular inter-actions were qu-anti-fied and analysed using Hirshfeld surface analysis.

(E)-5-(4-Methyl-benzyl-idene)-1-phenyl-4,5,6,7-tetra-hydro-1H-indazol-4-one.

In the title compound, C21H18N2O, the non-aromatic six-membered ring adopts a distorted envelope conformation with one of the methyl-ene-C atoms being the flap atom. The dihedral angle between the phenyl and 4-tolyl rings is 75.3 (1)°. The 1,2-diazole ring forms dihedral angles of 41.9 (1) and 65.5 (1)° with the phenyl and 4-tolyl rings, respectively. In the crystal, stabilizing C-H⋯O, C-H⋯π and π-π inter-actions are evident. The calculated Hirshfeld surfaces highlight the prominent role of C-H⋯O inter-actions (8.6%), along with H⋯H (51.7%) and C⋯H/H⋯C (29.2%) surface contacts.

(E)-5-(4-Chloro-benzyl-idene)-1-phenyl-4,5,6,7-tetra-hydro-1H-indazol-4-one: crystal structure and Hirshfeld surface analysis.

In the title compound, C20H15ClN2O, the non-aromatic six-membered ring adopts a distorted envelope conformation with methyl-ene-C atom nearest to the five-membered ring being the flap atom. The dihedral angle between the phenyl and chloro-benzene rings is 74.5 (1)°. The heterocyclic ring forms dihedral angles of 37.9 (1) and 64.3 (1)° with the phenyl and chloro-benzene rings, respectively. In the crystal, weak C-H⋯O inter-actions feature predominantly within the three-dimensional architecture. The inter-molecular inter-actions are further analysed with the calculation of the Hirshfeld surfaces highlighting the prominent role of C-H⋯O inter-actions, along with H⋯H (36.8%) and C⋯H/H⋯C (26.5%) contacts.