Model for the reduced Schiff base intermediate between amino acids and pyridoxal: copper(II) complexes of N-(2-hydroxybenzyl)amino acids with nonpolar side chains and the crystal structures of [Cu(N-(2-hydroxybenzyl)-D,L-alanine)(phen).H2O and [Cu(N-(2-hydroxybenzyl)-D,L-alanine)(imidazole)]

Complexes with bi- or tridentate coordination modes, mono- and dideprotonated ligands are produced by the controlled reduction of amino acids with nonpolar side chains and salicylaldehyde binding copper(II). The complexes are composed of chiral amino acid derivatives with Cu(II) units that can be utilized as models for biological racemization and transamination reactions of amino acids. The antiferromagnetic coupling between the Cu(II) centers of the complexes is caused by the phenolato-bridged, dimeric structure of the dianionic ligands.