Two one‐dimensional coordination polymers generated from a new benzimidazole bridging ligand and CdX2 (X = Br and I)

The novel asymmetric bridging ligand 1‐(pyridin‐3‐yl)methyl]‐2‐4‐(pyridin‐3‐yl)phenyl]‐1H‐benzimidazole (L) has been used to construct the coordination polymers catena‐polydibromidocadmium(II)]‐μ₃‐1‐(pyridin‐3‐yl)methyl]‐2‐4‐(pyridin‐3‐yl)phenyl]‐1H‐benzimidazole] monohydrate], {CdBr₂(C₂₄H₁₈N₄)]·H₂O}_n, (I), and catena‐polydiiodidocadmium(II)]‐μ₃‐1‐(pyridin‐3‐yl)methyl]‐2‐4‐(pyridin‐3‐yl)phenyl]‐1H‐benzimidazole], CdI₂(C₂₄H₁₈N₄)]_n, (II). Compounds (I) and (II) are closely related one‐dimensional polymers based on 16‐ and 20‐membered macrocycles along the chains, but they are not isomorphous. The chains are crosslinked into a two‐dimensional network via hydrogen bonds and π–π interactions in (I), and into a three‐dimensional framework through π–π interactions in (II). One well‐ordered solvent water molecule per asymmetric unit is included in (I) and forms O...Br hydrogen bonds.