Copper(II) complexes of 2-hydroxyethylamine react with acetone, pentan-2-one, or butan-2-one to form copper complexes of a linear quadridentate ligand which has two hydroxyethylamine residues linked by an amine–imine bridging unit containing two ketone residues. The copper complexes are isolated with one of the hydroxyethylamine residues deprotonated and a single nitrate or perchlorate anion.