N-Hydroxy-N-naphthylbenzamides (3) were synthesized for examining thei
r ability to extract and transport Cu(II) through a liquid membrane. T
he transport was proton-driven and was capable of moving metal ions 'u
p-hill'. Thus, it was possible to follow the transfer of Cu(II) from t
he aqueous source phase to the organic layer and from the organic laye
r to the receiving phase. The N-hydroxy-N-(2-naphthyl)benzamide (3b) c
arrier displayed much more remarkable selectivity for Cu(II) compared
with N-hydroxy-N-(l-naphthyl)benzamide (3a). This difference in select
ivity was explained in terms of the stability of the Cu(II) complex in
chloroform. (C) 1998 Elsevier Science B.V.