S. Abe et al., LIQUID-LIQUID-EXTRACTION OF IRON(III) AND GALLIUM(III) WITH MACROCYCLIC SCHIFF-BASES CONTAINING BISPHENOL-A SUBUNITS, Analytica chimica acta, 319(3), 1996, pp. 387-392
The quantitative extraction of iron(III) and gallium(III) was investig
ated with the recently synthesized macrocyclic Schiff base containing
bisphenol A subunits. The phenol groups in the Schiff base moiety led
to a large increase in the percent extraction of trivalent metal ions.
The substitution of methoxy groups for phenolic OH ligands resulted i
n a marked decrease in the extractability of metal ions, and no iron(I
II) was extracted. The corresponding acyclic Schiff base was found to
have a reasonable reactivity toward metal ions and a better solubility
in organic solvents. The iron(III) and gallium(III) complexes with ma
crocyclic and acyclic Schiff bases were quantitatively extracted into
nitrobenzene without the presence of bulky counter anions. A single ex
traction gave a good separation of iron(III) from iron(II) in the mole
ratios 4:1 to 1:3. The red iron(III) complexes can be used for the ex
traction-spectrophotometric determination of iron(III). The apparent m
olar absorptivity at 518 nm is 5.43 X 10(3) 1 mol(-1) cm(-1).