Preparation of Some as-Triazines, Their Evaluation as Spectrophotometric Reagents and Determination of Trace Amount of Iron in Certain Food and Natural Samples

Spectrophotometric reagents 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT) and 3-(2-pyridyl)-5,6-bis(p-methoxyphenyl)- 1,2,4-triazine (PBMPT) were prepared from commercially available reactants simply by condensing pyridyl-2-hydrazidine with 1,2-dicarbonyl compounds. These organic reagents were used further to determine the trace amount of iron in various natural and food samples by spectrophotometric method. The absorptiometric features of iron (II) complexes of PDT and PBMPT were determined. The molar absorptivites of iron (II) complexes of PDT and PBMPT were found to be 24,181 L mol-1 cm-1 (at 556.0 nm) and 32,091 L mol-1 cm-1 at (561.8 nm) respectively. The reliability of these absorptivities were verified by standard addition technique and also by comparing the results of atomic absorption spectroscopy method. The complexes of both the reagents obey Beer’s law within the experimental concentration range 0.032mg/L - 0.159 mg/L. Dhaka Univ. J. Sci. 71(2): 111-116, 2023 (July)