The thermal dehydration of pentacoordinate complexes [Cu(maleinate)(H2O)] (I), [Cu2(citrate) (H2O)2] (II) and [Cu(phenoxyacetate)2(H2O3] (III) was investigated and correlated with the structural changes occurring during the dehydration. It was found that the
activation parameters of the reactions do not follow the lengths of the split Cu−OH2 bonds. The lowestEa and lgA values were found for compound I, the highest ones for compound III. The most expressive changes of the anionic ligand binding
mode take place during the dehydration of this compound.