STUDIES OF 1,5-BIS(3,4,5-TRIMETHOXYPHENYL)-3-MERCAPTOFORMAZANS AND 1,5-BIS(2-METHOXY-4-METHYLPHENYL)-3-MERCAPTOFORMAZANS AND THEIR REACTIONS WITH METAL-IONS

1,5-Bis(3,4,5-trimethoxyphenyl)- and 1,5-bis(2-methoxy-4-methylphenyl)-3-mercaptoformazans have been prepared and characterized, and their reactions with metal ions in a two-phase system are reported. The extraction equilibria of their metal complexes with Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Pb(II), Tl(I) and Zn(II) as well as their spectral characteristics are also described. The molar absorptivities of Pb(II) and Zn(II) complexes with 1,5-bis(3,4,5-trimethoxyphenyl)-3-mercaptoformazan are higher than the corresponding values of their complexes with dithizone. The molar absorptivities of Cu(II) and Cd(II) complexes with 1,5-bis(2-methoxy-4-methylphenyl)-3-mercaptoformazan are also higher than the corresponding values of the dithizone complexes. 1,5-Bis(2-methoxy-4-methylphenyl)-3-mercaptoformazan is more efficient than dithizone in the separation of Cd(II) from Zn(II).