Ferromagnetic chloro-bridged copper(II) coordination polymer: Synthesis, structure, magnetism, and DNA cleavage effects

A new coordination polymer, [Cu(pmaeOH)Cl₂]_n, based on the copper(II) ion and 2-(2-pyridine-2-ylmethylamino)ethanol (pmaeOH) ligand was obtained from a methanol solution. The coordination polymer was characterized by elemental analysis, infrared spectroscopy, X-ray single-crystal diffraction, magnetic susceptibility measurements, and DNA cleavage effect. The crystal structure of the polymer consisted of a one-dimensional (1-D) chain with each copper(II) atom six-coordinated (by three nitrogen atoms and three chlorine atoms) in a severely distorted octahedral geometry. The polymer exhibited ferromagnetic behavior within the 1-D chain (J = 6.35 cm⁻¹) through the long bond distances of copper(II) and chloride ions. The copper(II) complex cleaves scDNA through oxidative pathways, where the reactive oxygen species (ROS) involved in DNA cleavage are the superoxide radical (⋅O₂^–), singlet oxygen (¹O₂), and hydrogen peroxide (H₂O₂). This paper reports the new synthesis of a ferromagnetically coupled polymer bridged with a chloride ion and its DNA cleavage effect for molecular memory devices and DNA repair applications.