Crystal structure of 3,14-dimethyl-2,6,13,17-tetra-azoniatri-cyclo-[16.4.0.07,12]docosane tetra-chloride tetra-hydrate from synchrotron X-ray data.

The crystal structure of the title salt, C20H44N44+·4Cl-·4H2O, has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at all four amine N atoms. The asymmetric unit contains one half-cation (completed by crystallographic inversion symmetry), two chloride anions and two water mol-ecules. There are two mol-ecules in the unit cell. The Cl- anions and hydrate mol-ecules are involved in hydrogen bonding. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the macrocycle N-H groups and water O-H groups as donors and the O atoms of the water mol-ecules and the Cl- anions as acceptors, giving rise to a three-dimensional network.