Complex formation between copper(II) and several beta-amino alcohols in aqueous solution: a potentiometric and spectrophotometric study

The behaviour of solutions containing copper(II) and several beta-amino alc ohols was examined by potentiometric and spectrophorometric techniques. The potentiometric results at 25 degrees C and KNO3 0.5 M, indicates in all th e examined systems the formation of four main species with M:L:H stoichiome try 1:1:0, 1:1:-1, 1:2:-1 and 1:2:-2, respectively. The deprotonated specie s have been demonstrated to be alkoxo chelates formed by the loss of alcoho lic hydrogen. No evidence of formation of ternary hydroxy or polynuclear co mplexes have been found in the examined experimental conditions, and the ab sence of dimeric alkoxo-bridged species have been confirmed by the analysis of the UV charge-transfer bands. The dependence of complex stability on th e ligand structure is discussed with particular regard to the influence exh erted by the number of hydroxyl groups. Also, the comparison with the behav iour of other metal ions is discussed. (C) 1999 Elsevier Science Ltd, All r ights reserved.