Abstract:

The title reactions with R=Me, Et, n-Pr were studied in a temperature range of 298-313K by spectrophotometry. It was found that the rate with respect to [complex] is unity and that to [amine] is fractional. A linear relationship between [amine]/kobs and [amine] was observed, where kobs stands for pseudo-first-order rate constant. The rate increases with the increase in water content of the solvent. A mechanism involving a preequllibrium of an adduct formation between the complex and amine was proposed. The equation derived from the mechanism explained all the experimental results and the preequllibrium constants, rate constants of the rate-determing step along with the activation parameters were evaluated.

Key words: Alkylxanthatocobalt(III), Dipropylamine, Kinetics of reactions