Proton ligand and metal ligand stability constants of substituted salicylaldehydes

Abstract

Proton affinity constants of β-resorcyl aldehyde and gentistic aldehyde and stability constants of the metal complexes of these reagents with metal ions UO 2 2+, Cu 2+, Ni 2+, Co 2+, Zn 2+, Cd 2+, and Mg 2+ are determined in aqueous-dioxan medium containing 50% dioxan by volume and 0·1 M NaClO 4 with concentrations of metal ion 10 −3 M and reagent 10 −2 M using Calvin-Bjerrum pH titration technique as applied by Irving and Rossotti. The values of the proton association constants of the reagents are interpreted in terms of inductive effects of substituted groups in benzene.