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)<sub>2</sub>] (<b>1</b>), two-dimensional (2D) coordination polymers [M(L)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>]·(NO<sub>3</sub>)<sub>2</sub> [M = Zn (<b>2</b>), Cd (<b>3</b>)], and a one-dimensional (1D) double-bridged complex [Cd(L)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>]·(ClO<sub>4</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub> (<b>4</b>), where anions could tune the self-assemblies to form different supramolecular and coordination networks. Compound <b>1</b> 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 CdN<sub>4</sub>O<sub>2</sub> polyhedra from 2D to 1D coordination polymers for <b>3</b> and <b>4</b>, respectively.