Influence of the ammonium cation and 18-crown-6 guest on the supramolecular networks of 1,3,5-cyclohexanetricarboxylic acid

The title acid 1,3-cis,5-cis-cyclohexanetricarboxylic acid (H(3)CTA) forms a three-dimensional anionic host framework via O-H center dot center dot center dot O- hydrogen bonds with 11.2 x 12.7 angstrom square channels for the inclusion of 18-crown-6 (18-C-6) and NH4+ cation in a Russian doll assembled guest boolean AND cavitand subset of clathrand crystal structure, H(2)CTA(-)center dot H2O center dot NH4+center dot 18-C-6 (1). Differences in the binding of the ammonium cation to the crown ether and OHNH3+ cation result in a two-dimensional network of H2CTA- anions in H(2)CTA(-)center dot OHNH3+center dot 18-C-6 (2) that resemble the black phosphorus topology. In contrast to ionic structures 1 and 2, crystal structure of the neutral complex H(3)CTA center dot(18-C-6)(0.5) (3) is sustained by a size/shape fit of the crown macrocycle in the 14.5 x 14.5 angstrom hexagonal cavity of the triacid host and 12 C-H center dot center dot center dot O interactions.