Self-Assembly of Right-Handed Helical Infinite Chain, One- and Two-Dimensional Coordination Polymers Tuned via Anions

Using similar synthesis conditions and a flexible ligand, 1,2-bis(1,2,4-triazole-1-yl)ethane (L), we isolated novel right-handed helical infinite chain [Zn(L)(Cl)₂] (1), two-dimensional (2D) coordination polymers [M(L)₂(H₂O)₂]·(NO₃)₂ [M = Zn (2), Cd (3)], and a one-dimensional (1D) double-bridged complex [Cd(L)₂(H₂O)₂]·(ClO₄)₂(H₂O)₂ (4), where anions could tune the self-assemblies to form different supramolecular and coordination networks. Compound 1 is the first infinite helix in triazole compounds, where the supramolecular helical chain and the coordination chain form a unique double helical structure. Nitrate and perchlorate anions induced different supramolecular structures, which lead to the first case of the self-assembled CdN₄O₂ polyhedra from 2D to 1D coordination polymers for 3 and 4, respectively.