Current time in Korea 01:32 Oct 18 (Wed) Year 2017 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 24, Number 7
BKCSDE 24(7)
July 20, 2003 

Kinetics and Mechanism of the Pyridinolysis of Aryl Cyclopropanecarboxylates in Acetonitrile
Han Joong Koh, Suk Jin Kang, Cheol Ju Kim, Hai Whang Lee, Ikchoon Lee
Aryl cyclopropanecarboxylates, Stepwise mechanism, Zwitterionic tetrahedral intermediate, Cross interaction constant, Reactivity-selectivity principle
Kinetic studies of the reaction of Z-aryl cyclopropanecarboxylates with X-pyridines in acetonitrile at 55.0 oC have been carried out. The reaction proceeds by a stepwise mechanism in which the rate-determining step is the breakdown of the zwitterionic tetrahedral intermediate, T±. These mechanistic conclusions are drawn base on (i) the large magnitude of rX and rZ, (ii) the positive sign of rXZ and the larger magnitude of rXZ than normal SN2 processes, (iii) a small positive enthalpy of activation, DH¹, and a large negative, DS¹, and lastly (iv) adherence to the reactivity-selectivity principle (RSP) in all cases.
925 - 930
Full Text