Spectrophotometric Determination of Tin (IV) in Solder and Brass Using 6-[(E)-(1,5-Dimethyl-3-Oxo-2-Phenyl-2,3-Dihydro-1h-Pyrazol-4-Yl)Diazenyl]-1h-Indole-2,3-Dione

In the present paper, a new method is proposed for the spectrophotometric determination of tin (IV) in solder and brass. The ligand, 6- [ (E) - (1, 5-dimethyl-3-oxo-2-phenyl-2, 3-dihydro-1H-pyrazol-4-yl) diazenyl]-1H-indole-2, 3-dione was synthesized by coupling diazotized 1-phenyl-2, 3-dimethyl-4-aminopyrazole-5-one and 1H-indole-2, 3-dione. It formed coloured complex with Sn (IV). The ligand and complex were characterized via UV, IR and NMR spectroscopy. The analytical data show that Sn (IV) formed complex, with 2: 1 metal-ligand stoichiometry when reacted with the ligand respectively. Sn (IV) was determined spectrophotometrically by measuring the absorbance at 421.4 nm. Beers law was valid between 0.34-2.81 ppm, with calibration and analytical sensitivities of 0.068 and 67.00 ppm respectively. Very few elements were found to interfere in the method. The method is quite simple and useful; its applicability has been tested by the analysis of solder and brass.