RATES OF FORMATION OF ISOPERTHIOCYANIC ACID (5-AMINO-1,2,4-DITHIAZOLE-3-THIONE) FROM THIOCYANATE IN AQUEOUS SOLUTION

The rates of formation of 5-amino-1,2,4-dithiazole-3-thione from potassium thiocyanate in aqueous sulphuric acid have been studied spectrophotometrically. They show close to third-order dependence on thiocyanate concentration and linear dependence on the Hammett acidity function, h−. Between 25 and 45° the rate constant is given by the Arrhenius expression k = 9.27 × 10−5exp(−8800/T) 1.2 mole−2 sec−1 A mechanism is proposed. © 1969, CSIRO. All rights reserved.