Three-dimensional supramolecular structures in (E,E)-N,N'-bis(4-nitrobenzylidene)butane-1,4-diamine and (E,E)-N,N'-bis(4-nitrobenzylidene)hexane-1,6-diamine.

In both (E,E)-N,N'-bis(4-nitrobenzylidene)butane-1,4-diamine, C18H18N4O4, (III), and (E,E)-N,N'-bis(4-nitrobenzylidene)hexane-1,6-diamine, C20H22N4O4, (IV), the molecules lie across centres of inversion in space groups P-1 and P2(1)/c, respectively. In (III), the three-dimensional supramolecular structure is built from pi-stacked chains of edge-fused R(2)(2)(30) rings, while in (IV), chains of edge-fused R(2)(2)(38) rings are linked by dipolar nitro-nitro interactions.