Enforced 2D supramolecular structures within hydrogen-bonded molecular cocrystals

Abstract

Two new coordination polymers, {[Co(btmb)2(H2O)2] · (Fc(SO3)2)} n (1) and {[Cd(bbbm)(H2O)4] · (p-FcC6H4SO3)2(CH3OH)} n (2) (Fc = ferrocene; btmb = 1,4-bis(triazol-1-ylmethyl)benzene); bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole), were synthesized as cocrystals and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. In 1, two btmb molecules link Co(II) ions into one 1D double-stranded chain of loops, and these chains are bridged by ligands through H-bonds, resulting in an infinite 2D sandwich-type network. In 2, two adjacent Cd(II) ions are interconnected by bbbm to generate a 1D zigzag chain structure, and squeezes like a wedge into the adjacent chains, further being assembled by O–H ··· O hydrogen bonds and π–π stacking interactions to form a 2D supramolecular network.