Crystal Structure of Dimeric [4-{(2-Oxybenzyl)imino}-2-penten-2-olato-O,O′,N]copper(II) Complex

Abstract

Due to the super exchange mechanism over the O atoms, dimeric copper(II) complexes with double oxygen bridges show subnormal magnetic moments. [1][2][3] There seems to be correlations between the magnetic properties of the systems and the dihedral angle between the bridging plane and the coordination square around copper, as well as with the Cu-O-Cu bridging angle. As a contribution of our previous work 4-7 on dimeric Cu complexes, this structure determination was performed to obtain more information about the stereochemistry around the copper atom.The crystalline ligand 4-[(2-hydroxybenzyl)imino]-2-hydroxy-2-penten was prepared from the mixture of 2-hydroxybenzylamine (1.23 g; 0.01 mol) and acetylacetone (1.0 g; 0.01 mol) in 30 ml of hot ethanol after 24 h in air. To a solution of the ligand (0.205 g; 1 mmol) in 40 ml DMF above 130˚C, a solution of Cu(CH 3 COO) 2 · H 2 O (0.199 g; 1 mmol) in 20 ml hot methanol was added dropwise and the mixture was set aside. The crystals were obtained after allowing the solution to stand for 36 h at room temperature. The chemical reaction of the title compound is shown in Fig. 1.The complex includes two Cu(C 12 H 13 NO 2 ) structure units linked via phenolic O atoms (Fig. 2)