A chiral 3D polymer with right- and left-helices based on 2,2′-biimidazole: Synthesis, crystal structure and fluorescent property

A novel three-dimensional (3D) polymer [Cd2(Hbiim)4]n (H2biim = 2,2′-biimidazole) 1 was obtained through hydrothermal reaction and characterized by single crystal X-ray diffraction, and the fluorescent property was also determined. Compound 1 crystallizes in a monoclinic chiral space group P21 and contains two types of helical chains. Hbiim− partially deprotonated of H2biim exhibits two different coordination modes, which contributes greatly to the formation of the 3D chiral framework. Compound 1 exhibits blue fluorescence at 488 nm in the solid-state upon excitation at 430 nm.