ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 33, Number 4
JKCSEZ 33(4)
August 20, 1989 

Kinetics of the substitution reaction of [pt[dien]X]+(X = Cl-, Br-, I-) with NO2- in aqueous solution were investigated by a spectrophotometric method at 20-35℃ and 1-1500 bars. The rates of these reactions were increased with raising temperature and pressure. The relative reactivities of replaceable ligands in [pt[dien]X]+ follow the order (Cl- > Br- > I-). Activation volumes (│ΔV≠│) were large negative values and decreased with raising temperature. First (k1) and second(k2) order rate constants of these reactions were determined at 25℃ and both k1 and k2 were increased with raising pressure and activation volumes (ΔV1≠, ΔV2≠) for the k1 and k2 path were large negative values respectively. The k1 and k2 of these reactions were determined at 1 bar and these values were increased with raising temperature. Activation parameters of k1 and k2 path were determined, therefore it can be inferred frp, these results that the substitution reactions of [pt[dien]X]+ with NO2- proceed through on associative (A) mechanism independent of a leaving groups and reaction paths.