The reagent, bis-3,3'-(5,6-dimethyl-1,2,4-triazine) (BDMT), forms intensely colored complexes with selected transition metal ions. The reagent is water-soluble and easily prepared. An intense orange complex, Fe(BDMT)32+;is formed on reaction of iron(II) with the reagent in aqueous solution at pH 4.0-7.0. Nuclear magnetic resonance data show that chelation occurs between the 2,2'-nitrogens of the reagent. The complex exhibits absorption maxima at 408 mμ, with molar absorptivities of 12,000 and 15,000 respectively. The perchlorate salt of the complex is readily extracted into nitrobenzene. A proposed spectrophotometric method for the determination of iron is both accurate and precis. © 1965.
Jensen, R. E., & Pflaum, R. T. (1965). Investigation of the iron(II) complex of bis-3,3’-(5,6-dimethyl-1,2,4-triazine). Analytica Chimica Acta, 32(C), 235–244. https://doi.org/10.1016/S0003-2670(00)88929-1