One-dimensional copper(II) coordination polymers based on 1,3-bis(pyridin-4-yl)propane and diimine ligands

Abstract

Two one-dimensional (1D) coordination polymers (CPs), namely catena-poly[[[aqua(2,2'-bipyridine-κ²N,N')(nitrato-κO)copper(II)]-μ-1,3-bis(pyridin-4-yl)propane-κ²N:N'] nitrate], {[Cu(NO₃)(C₁₀H₈N₂)(C₁₃H₁₄N₂)(H₂O)]·NO₃}_n (1), and catena-poly[[[aqua(nitrato-κO)(1,10-phenanthroline-κ²N,N')copper(II)]-μ-1,3-bis(pyridin-4-yl)propane-κ²N:N'] nitrate], {[Cu(NO₃)(C₁₂H₈N₂)(C₁₃H₁₄N₂)(H₂O)]·NO₃}_n (2), have been synthesized using [Cu(NO₃)(NN)(H₂O)₂]NO₃, where NN = 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen), as a linker in a 1:1 molar ratio. The CPs were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray structure determination. The 1,3-bis(pyridin-4-yl)propane (dpp) ligand acts as a bridging ligand, leading to the formation of a 1D polymer. The octahedral coordination sphere around copper consists of two N atoms from bpy for 1 or phen for 2, two N atoms from dpp, one O atom from water and one O atom from a coordinated nitrate anion. Each structure contains two crystallographically independent chains in the asymmetric unit and the chains are linked via hydrogen bonds into a three-dimensional network.

Keywords: bridging ligand; copper(II) complexes; crystal structure; hydrogen bonding; one-dimensional coordination polymer.