Current time in Korea 06:00 Jul 17 (Wed) Year 2019 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(JKCS) > Archives

Journal of the Korean Chemical Society (JKCS)

ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 30, Number 4
JKCSEZ 30(4)
August 20, 1986 

 
Title
Studies on the Reaction of 2-Phenylethyl Arenesulfonates with Pyridine under High Pressure

2-Phenylethyl Arenesulfonates와 피리딘과의 고압반응에 관한 연구
Author
Soo-Dong Yoh, Jong-Hwan Park

여수동, 박종환
Keywords
Abstract
2-phenylethylarenesulfonates와 피리딘과의 아세토니트릴 용매중에서의 반응속도를 40∼60℃, 1 ~ 2,000 bar에서 전기 전도도법으로 측정하였다. 반응속도는 온도가 높아지고 압력이 커짐에 따라 증가하였으며 아세톤 용매내에서 benzyl benzenesulfonate보다 음의 값으로 컸다. 따라서 본 반응의 2-phenylethyl계가 전이 상태에서 벤질계보다 SN2성이 크다고 추정된다. Hammett도시한 결과는 압력의 증가에 따라 값이 감소하여 SN2성이 증가하였다. 이들의 모든 결과로 부터 고압하에서의 본 반응은 SN2메카니즘으로 진행되며 압력의 증가는 SN2반응성을 더욱 조장하였다.

Kinetics of the reaction of 2-phenylethylarenesulfonates with pyridine in acetonitrile were investigated by an electric conductivity method under 1 to 2,000 bars and at 40∼60℃. The rates of these reactions were increased with raising temperatures and pressures, but less than those of the reactions of benzyl benzenesulfonate with pyridine in acetone. The activation volumes and activation entropies of 2-phenylethyl m-nosylate were more negatively large than those of benzyl benzenesulfonate. From these phenomena it can be deduced that 2-phenylethyl system has more firmly SN2 character in tranistion state. The Hammett reaction constants are also estimated from the second-order reaction constants. With increasing pressures the reaction parameters (ρ) were decreased, but the SN2 characters were increased. From these results, the reaction mechanism can be adequately described as typical SN2 process under high pressure.

Page
383 - 388
Full Text
PDF