- P-ISSN 1225-0163
- E-ISSN 2288-8985
The podands I-VII, acyclic polyethers, expected high extractability for <TEX>$Ag^+$</TEX> against <TEX>$Pb^{2+}$</TEX> were designed and synthesized with high yields. Using podands I-VII as extractants, the %extraction(%Ex) of <TEX>$Ag^+$</TEX> and <TEX>$Pb^{2+}$</TEX> as picrates were determined in water/chloroform systems. The stability constants(log K) for the complexation of <TEX>$Ag^+$</TEX> with podands I-VII were also determined by potentiometry. %Ex(<TEX>$Ag^+$</TEX>) were proportional to the numbers of substituted sulfur donor atoms. Podand VI(log K : 7.65) having 3 substituted sulfur and podand VII(log K : 9.15) having 4 substituted sulfur, however, exhibited almost 100% of extractability, respectively. In %Ex(<TEX>$Ag^+/Pb^{2+}$</TEX>, oxygen-sulfur mixed donor podands(IV-VII) showed the higher values. Otherwise, the values of log K and %Ex(<TEX>$Ag^+$</TEX>) largely depended on the variation of donor-site of sulfur. From the results of NMR experiments, it seems that it is due to the <TEX>${\pi}-{\pi}$</TEX> stacking interaction between the aromatic end-groups.