Thermodynamic study on oxime complexes: the relative co-ordinating power of ketone, oxime, and amine functional groups

Thermodynamic data (ΔG, ΔH, ΔS) are reported for the reaction of the diamine-dioxime 4,4,9,9-tetramethyl-5,8-diazadodecane-2,11-dione dioxime with protons and copper(II) ions in aqueous solution. Data for the formation of the copper complexes are compared with data for the analogous diamine-diketone 4,4,9,9-tetramethyl-5,8-diazadodecane-2,11-dione and the analogous tetra-amine 2,11-diamino-4,4,9,9-tetramethyl-5,8-diazadodecane. The relative co-ordinating powers of different donor groups in these structurally related ligands are amine > oximato ∼ oxime > ketone (∼H2O).