A New Reagent for Determination of Copper(ll) : 2-(α-Pyridyl)thioquinalidinamide

Department of Chemistry, Jadavpur University, Calcutta-700 032

Manuscript received 9 December 1981, revised 26 March 1985, accepted 31 July 1985

A new sulphur reagent for copper(II) has been synthesised for its detection and determination. A very simple, rapid and useful spectrophotometric method for trace analysis of copper has been developed and reported in this paper. A blue-violet copper(II) chelate formed over a wide $p$H range 0.5-6.5. Copper(II) has been determined in presence of V^v, Mo^VI, W^VI, U^VI, Pb^II, Fe^III, Bi^III, in presence of masking agents. Alloy steel samples have been analysed for trace analysis of copper. A 1 : 3 (M-R) composition of the complex has been determined. The overall stability constant of the chelate is found to be 13.04 (log K) in 50% ethanol-water at 27 ± 1°.