A New Reagent for Spectrophotometric Determination of Ir(IV): 5-[2-(4-Hydroxyphenyl)hydrazineylidene]-4-iminothiazolidin-2-one (HPIT)

Abstract

The paper presents a new azolidone derivative – 5-[2-(4-hydroxyphenyl)hydrazineylidene]-4-iminothiazolidin-2-one (HPIT) studies and its interaction results with iridium(IV) ions. The Ir(IV) with this reagent in the pH = 5.0 without heating forms a stable complex (λ_max = 328 nm). The stoichiometric ratio of Ir(IV) to the reagent in complex is 1:1. The molar absorptivity and Sandell’s sensitivity are 5.57×10³ L mol^-1 cm^-1 and 0.034 µg cm^-2 respectively. The calibration curve is linear in the range of 1.0-11.5 µg mL^-1 of Ir(IV) (R = 0.9996). The limit of detection is 0.4 µg mL^-1. Based on the conducted investigation a rapid and simple, spectrophotometric method for the determination of Ir(IV) using 5-[2-(4-hydroxyphenyl)hydrazineylidene]-4-iminothiazolidin-2-one as a chromophoric reagent was developed. The iridium(IV) was determined in various synthetic mixtures and alloys.