Crystal structure of N,N′-bis­­(pyridin-3-ylmeth­yl)cyclo­hexane-1,4-di­ammonium dichloride

The title salt, C18H26N42+·2Cl−, was obtained by the protonation of N,N-bis­(pyridin-4-ylmeth­yl)cyclo­hexane-1,4-di­amine with hydro­chloric acid in ethanol. The asymmetric unit consists of one half of an N,N-bis­(pyridin-3-ylmeth­yl)cyclo­hexane-1,4-di­ammonium dication, with a crystallographic inversion centre located at the centre of the cyclo­hexyl ring, and a chloride anion. The central cyclo­hexyl ring in the dication adopts a chair conformation. The two trans-(4-pyridine)–CH2–NH2– moieties at the 1- and 4-positions of the central cyclo­hexyl ring occupy equatorial sites. The terminal pyridine ring is tilted by 53.72 (6)° with respect to the mean plane of the central cyclo­hexyl ring (r.m.s. deviation = 0.2413 Å). In the crystal, N+—H⋯Cl− hydrogen bonds between the dications and the chloride anions, and π–π stacking inter­actions between the pyridine rings of the dications afford a two-dimensional sheet extending parallel to the ab plane. These sheets are further connected through weak C—H⋯Cl− hydrogen bonds, resulting in the formation of a three-dimensional supra­molecular network.