A Study on the Kinetics and Mechanism of Nucleophilic Addition of 1-Propanethiol to ${\alpha}-Phenyl-N-iso-propylnitrone$ Derivatives.

(${\alpha}-Phenyl-N-iso-propylnitrone$유도체에 대한 1-Propanethiol의 친핵성 첨가반응에 관한 연구

The rate constant of the nucleophilic addition of 1-propanethiol to ${\alpha}-phenyl-N-iso-propylnitrone$ derivatives were determined at various pH and a rate equation which can be applied over wide pH range is obtained. Final product of the addition reaction was ${\alpha}-thiopropyl-p-phenylbenzylideneamine$. Base on the rate equation, general base effect, substituent effect and final product, plausible mechanism of addition reaction have been proposed. Below pH 3.0, the reaction was initiated by the addition of 1-propanthiol, and in the range of pH 3.0-10.0, proceeded by the competitive addition of 1-propanethiol and propanethiolate. Above the pH 10.0, the reaction proceeded through the addition of propanethiolate.