Modified BINOL Podands: Synthesis of Dinaphthosulfide Podands and Their Application in Spectrophotometric Determination of Toxic Metals.

New dinaphthosulfide podands [3(a, b, and c)] were synthesized. The structures of these compounds were confirmed by IR, 1H NMR, 13C NMR, and Mass spectra. A simple, efficient, and sensitive procedure is described for the spectrophotometric determination of a trace amount of Ag+, Hg2+, Cr3+, Pb2+, and Ni2+ cations in the presence of Mn2+, Co2+, Cd2+ cations using the podand (3a). Formation constants of 1:1 complexes were determined from the absorbance-mole ratio data and found to vary in the order Pb2+ > Ni2+ > Hg2+ > Cr3+ > Ag+. [ABSTRACT FROM AUTHOR]