Complexation of metal ions in monolayers of amphiphilic schiff bases at liquid/air interface

New amphiphilic schiff bases 2,4 dihydroxy hexadecyl benzilideneamine (HDBA) and 2,4 dihydroxy benzilidene-4′(hexadecylamino) benzylamine (HDBBA) have been synthesized and stable monolayers of these at air/water interface have been studied. Complexes of these ligands with metal ions Mn2+, Cu2+ and Zn2+ at the interface have been possible due mainly to the presence of the hydroxyl group adjacent to CN in the head groups, in both the ligands. These metal complexes have been studied using surface pressure/molecular area (π–A), surface potential/molecular area (ΔV–A) isotherms and surface enhanced UV–Vis reflection spectroscopy. The rate of formation of the metal complexes with the ligands HDBA and HDBBA at the liquid/water interface has been studied. The faster rate of formation of Cu2+ complex in the case of HDBBA indicates the specificity of binding of Cu2+ ion to its monolayer.