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

The title salt, C18H26N42+center dot 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)degrees with respect to the mean plane of the central cyclohexyl ring (r.m.s. deviation = 0.2413 angstrom). In the crystal, N+-H center dot center dot center dot Cl- hydrogen bonds between the dications and the chloride anions, and pi-pi 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 center dot center dot center dot Cl- hydrogen bonds, resulting in the formation of a three-dimensional supramolecular network.