By using the layer-by-layer deposition method, we build three dimensional (3D) supramolecular nanostructures by stacking small molecular species on top of the first buffer layer, which can be utilized to fabricate novel 3D supramolecular functional nanostructures.

In the title compound, C(18)H(14)N(4)O(2)·C(8)H(6)O(4), both types of mol-ecule lie on inversion centers. In the N,N'-bis-(pyridin-3-yl)terephthalamide mol-ecule, the pyridine ring forms a dihedral angle of 11.33 (9)° with the central benzene ring. In the crystal, N-H⋯O and O-H⋯N hydrogen bonds connect the components into a three-dimensional network.

A chemosensor compound (1) consisting of a central ferrocene with two butylaminomethyl arms showed unexpected facile electrochemical oxidation of the secondary amines in proximity to the ferrocene, which was utilized for electrochemical discrimination of phthalic acid selectively over two other isomers, isophthalic acid and terephthalic acid.

In the crystal structure of the title compound, 2C(8)H(6)O(4)·3C(20)H(22)N(4), there are three independent 2,2'-dimethyl-1,1'-(butane-1,4-di-yl)dibenzimidazole mol-ecules, each of which lies on an inversion centre. The terephthalic acid mol-ecules are linked to adjacent 2,2'-dimethyl-1,1'-(butane-1,4-di-yl)dibenzimidazole mol-ecules via O-H⋯N hydrogen bonds.