Disentangling steric and electronic factors in monomeric bis(2-bromo-4-chloro-6-{[(2-hydroxyethyl)imino]methyl}phenolato-κ(2)N,O)copper(II).

The title compound, [Cu(C9H8BrClNO2)2], is a square-planar complex. The potentially tridentate dibasic 2-bromo-4-chloro-6-{[(2-hydroxyethyl)imino]methyl}phenolate ligand coordinates in a trans-bis fashion to the Cu(II) centre via the imine N and phenolate O atoms. The Cu(II) atom lies on the centre of inversion of the molecule. The potentially coordinating hydroxyethyl group remains protonated and uncoordinated, taking part in intermolecular hydrogen bonds with vicinal groups, leading to the formation of a two-dimensional hydrogen-bond network with sheets parallel to the (101) plane. Substituent effects on the crystal packing and coordination modes of the ligand are discussed.