Ternary and quaternary co-crystals of 1,3-cis,5-cis-cyclohexanetricarboxylic acid and 4,4′-bipyridines

Abstract

1,3cis,5cis-Cyclohexanetricarboxylic acid (H₃CTA) was co-crystallized with 4,4′-bipyridine bases connected viamethylene and alkene chains to obtain ternary acid–base co-crystals, H₃CTA·bipy1·bipy2. The hydrogen bond network and mode of interpenetration in co-crystal structures are discussed in relation to known (6,3) nets. The rectangular host container of composition H₃CTA·bipy-eta·(bipy-bu)_0.5 includes a variety of aromatic guest species in its 10 × 12 Å channels. The ternary and quaternary co-crystals are characterized by X-ray diffraction to analyze the hydrogen bonding and molecular packing. Whereas the acid–pyridine O–H⋯N hydrogen bond sustains reliable supramolecular aggregation in multi-component crystal structures, the change of bipyridine base connector imparts structural diversity in these supramolecular structures. A self-assembly model based on helix and chain sub-units of acid·bipy1 being connected via the bipy2 spacer to give hexagonal and square network structures is proposed.