Synthesis, crystal structure and characterization of two Cu(II) complexes assembled with flexible bistriazole butane

Using a flexible bis-triazole ligand 1,4-bis(1,2,4-triazol-1-y1)butane (btrb), two new copper(II) compounds [Cu0.5(btrb)0.5Cl]n (1) and [Cu0.5(btrb)Cl]n (2), have been isolated. Conformations of btrb can be tuned as a result of changing the metal/ligand ratio in the reaction system, which ultimately forms two novel framework structures. 1 is a three dimensional network with CdSO4 topology, and uncommonly six-fold Cl…H–C hydrogen bonds reside in the 3D framework. 2 possesses 2D (4.4) net framewok. Triple Cl…H–C hydrogen bonds reside among the 2D layers, which link the 2D layers to lead to a 3D supramolecular architecture. For 1 and 2, elemental analysis, thermal stability and EPR spectra have been carried out, and the conformational variation of btrb also has been discussed.