Co-crystals based on 1,2,4,5-Benzenetetracarboxylic Acid: Synthesis, Supramolecular Frameworks and Optical Properties



Two new co-crystals based on 1,2,4,5-benzenetetracarboxylic acid, (H2BETC)(H4tpim)](NO3) (1) and [(H4BETC)0.5(H2BETC)0.5(HVB4)](H2O) (2) [H4BETC = 1,2,4,5-benzenetetracarboxylic acid, Htpim = 2,4,5-tri(4-pyridyl)-imidazole, and VB4 = adenine], were synthesized and characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, and X-ray powder diffraction analysis. Compounds 1 and 2 were further assembled to form 3D supramolecular frameworks with 1D channels by intermolecular C–H···O, O–H···O, and N–H···O hydrogen-bonding interactions. The results reveal that the structural differences of 1 and 2 may be attributed to different molecular components. Moreover, the UV/Vis and luminescent spectra of ligands and corresponding compounds were briefly investigated.