The seven-membered ring of the title compound, C25H40N2O2, adopts a boat-shaped conformation (with the C atoms of the fused-ring as the stern and the methine C atom as the prow). The tetra­decyl substituent occupies an equatorial position, with the tetra­dodecyl chain exhibibiting an an all-trans conformation.

The asymmetric unit of the title compound, C14H14N2O2, comprises two independent mol­ecules, which slightly differ in the orientation of the propargyl chain. In both molecules, the diazepine ring adopts a boat conformation with the propargyl-bearing C atom as the prow and the C atoms at the ring junction as the stern. The carbonyl O atom of one independent mol­ecule is hydrogen bonded to the acetyl­enic H atom of the other independent mol­ecule. In the crystal, symmetry-related mol­ecules are linked together by C—H⋯O hydrogen bonds, forming a ribbon-like structure along the c axis.

The seven-membered ring of the title compound, C15H11ClN2O2, adopts a boat-shaped conformation (with the C atoms of the fused-ring as the stern and the methyl­ene C atom as the prow). The N atoms exists in a trigonal–planar coordination; one of the acetyl­enic H atoms forms a C—H⋯O hydrogen bond to the O atom of an adjacent mol­ecule, generating a linear chain along a body diagonal.