Tetranuclear Copper(II) Complexes Derived from 5-Bromo-2-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol: Synthesis, Characterization, Crystal Structures and Catalytic Oxidation of Olefins.

An acetate bridged tetranuclear copper(II) complex, [Cu4L2(μ2-η1:η1-CH3COO)6(CH3OH)2] (1), and a chloride, phenolate and azide co-bridged tetranuclear copper(II) complex, [Cu4L2Cl2(μ-Cl)2(μ1,1-N3)2]2CH3OH (2), where L is the deprotonated form of the Schiff base 5-bromo-2-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol (HL), have been synthesized and characterized by elemental analysis, IR and UV spectra, and single crystal X-ray diffraction. Single crystal X-ray analysis revealed that the Cu atoms in both complexes are in square pyramidal geometry. In complex 1, two [CuL] units and [Cu2(μ2-η1:η1-CH3COO)4] core are linked through two acetate ligands.