Synthesis, Structures, and Characterization of Two d¹⁰ Metal Coordination Polymers With a Flexible Bis(triazole) Ligand

Abstract

Two d¹⁰ metal coordination polymers, {[Zn(mbtz)(HBTC)]·(H₂O)_0.5}_n (1) and {[Cd(mbtz)(HO−BDC)(H₂O)]}_n (2) (mbtz = 1,3-bis(1,2,4-triazol-1-ylmethyl)benzene, H₃BTC = 1,3,5-benzenetricarboxylic acid, and HO−H₂BDC=5-hydroxy-isophthalic acid), have been hydrothermally synthesized and characterized. 1 exhibits a one-dimensional (1D) loop-like chain structure, each Zn(II) ion is coordinated by two triazole nitrogen atoms derived from two mbtz ligands and two oxygen atom from two distinct HBTC²⁻. While 2 displays a two-dimensional (2D) undulated (4,4) network constructed with mbtz and HO−BDC²⁻ bridging ligands, each Cd(II) ion has distorted octahedral coordination geometry. Furthermore, both the coordination polymers extend to three-dimensional (3D) supramolecular net via hydrogen-bonding interactions, but different framework topologies. Complex 1 is a rare type of binodal (4,5)-connected topology with a point symbol of {3.4².6⁵.8²}{3².6.7².8}, while 2 is a trinodal (3,5,6)-connected topology, and the point symbol of the net is {3.5.6}{3².5².6⁸.7³}{5².6⁶.8²}.

Keywords:

• coordination polymer
• crystal structure
• flexible bis(triazole)
• hydrogen bond
• topology