Abstract
Kinetics of the reaction of 2-phenethyl p-bromobenzenesulfonate with substituted pyridines in acetonitrile were investigated by an electric conductivity method at 1-2000 bars and $45{\sim}55{\circ}C$. The rates of these reactions were increased with raising temperatures, pressures and by changing electron-donating substitutents in pyridine. When raising pressure the Hammett reaction parameter $I{\rho}I$ and Bronsted ${\beta}$ values were increased, and isokinetic temperature observed from isokinetic relations hip between ${\Delta}H^{\neq}$ and TEX>${\Delta}S^{\neq}$ was decreased. These results indicate that the $S_N2$ characters were increased with raising pressure.
2-phenethyl p-bromobenzenesulfonate와 치환피리딘과의 반응속도를 아세토니트릴 용매 중에서 $1{\sim}2,000bars$ 및 $45{\sim}55${\circ}C$에서 전기전도도법으로 측정하였다. 반응속도는 온도와 압력이 증가함에 따라서 증가하였으며 또한 피리딘에 전자주게 치환기가 도입됨에 따라 반응속도가 증가하였다. 압력이 증가함에 따라 Hammett $I{\rho}I$값과 Bronsted ${\beta}$값이 증가하였으며 등온속도는 점차 감소하였다. 이러한 결과들은 본 반응이 압력의 증가에 따라 SN2성이 증가함을 나타내었다.