Four macrocyclic polyamides, 6.20-diocty1-3, 6, 9, 17, 20, 23, 29, 30-octaazatricyclo[23.3.1.111, 15]triaconta1 (29), 11, 13, 15 (30), 25, 27-hexaene-2, 10, 16, 24-tetrone (L
1), 4-octy1-1, 4, 7-triazacyclotridecane8, 13-dione (L
2), 4-octy1-10- (2-pyridylmethyl) -1, 4, 7, 10-tetraazacyclododecane-2, 6-dione (L
3)and 4- (2-pyridylmethyl) -1, 4, 7-triazacyclotridecane-8, 13-dione (L
4) have been synthesized and the composition of the complex and the extraction equilibrium constants log Kex have been determined by solvent extraction for some transition metal ions (Cu
2+, Co
2+, Ni
2+, Zn
2+ ).
These ligands formed the cationic complexes as 1: 2 ( Ll: Cu
2+) and 1: 1 ( L
2 and L
3; Cu
2+), and extracted Cu
2+ selectively from an equeous solution in the presence of picrate ion into 1, 2-dichloroethane. Values log Kex for the cationic complexes of Cu
2+ with each ligand were increased in the order L
1 < L
2 < L
3.
In paticular, L
3 possessing a pyridine ring appendage of cooperative binding extracted Cu
2+ effectively even in a strong acidic equeous solution, and extracted Co
2+, Ni
2+, Zn
2+ with same extent to Cu
2+from a singl metal solution, however predominantly extracted only Cu
2+ in the competitive extraction of these ions and Cu
2+. L
1 and L
2 have little binding ability for Co
2+, Ni
2+ and Zn
2+ ions. L
4 was soluble to some extent in the equeous phase, thus it is not appropriate as a ligand of solvent extraction.
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