Copper(II) Coordination Polymers Assembled from 2-((Pyridin-3-ylmethyl)amino)ethanol: Structure and Magnetism

摘要

The one-dimensional coordination polymers, [Cu~(II)(L)(NO3)2]n (1) and {[Cu~(II)(L-H)(NO3)]·2H2O}_(2n) (2), were synthesized from Cu(NO3)2 · 3H2O and 2-[(pyridin-3-ylmethyl)amino]ethanol (L, PMAE) in methanol by controlling the molar ratio of copper(II) salt. Copper(II) ion in 1 has one pyridine group of PMAE whose an aminoethanol group coordinates adjacent copper(II) ion. As the pyridine group is bonded to neighboring copper(II) ion, 1 becomes a one-dimensional chain. Contrary to 1, the structure of 2 shows that the oxygen atom of ethoxide group is bridged between two copper(II) ions, which forms a dinuclear complex. Additionally, the pyridine group of PMAE included one dinuclear unit is coordinated to the other dimeric one each other, which leads to a one-dimensional polymer. Due to the structural differences, 1 exhibits weak antiferromagnetic interaction, while 2 shows strong antiferromagnetic interaction. Due to direct spin exchange via oxygen of PMAE 2 has a much strong spin coupling than 1.