Studies on Ti [IV], Zr [IV] and Th [IV] chelates of arylazochromotropic acid dyes

The TI [IV], Zr[IV] and Th[IV] chelates with 14 arylazo-chromotropic acid dyes are investigated. The chelates formed have the stoichiometric ratios 1 :1 and 1:2 [M : L]. The stability constants of the complexes [log K1 and log K2] are determined from pH-titrations and correlated with the substituent constants [sigma x]