Tetrahedron

Kinetics and mechanisms of the reactions of S-methyl chlorothioformate with pyridines and secondary alicyclic amines

EA Castro, M Aliaga, M Gazitúa, JG Santos

Index: Castro, Enrique A.; Aliaga, Margarita; Gazitua, Marcela; Santos, Jose G. Tetrahedron, 2006 , vol. 62, # 20 p. 4863 - 4869

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Citation Number: 26

Abstract

The pyridinolysis of S-methyl chlorothioformate shows a biphasic Brønsted-type plot, in agreement with a stepwise mechanism and a change in the rate-limiting step, from formation of a zwitterionic tetrahedral intermediate (T±) at high pKa to its breakdown at low pKa. The reaction of the same substrate with secondary alicyclic amines shows a linear Brønsted-type plot of slope 0.23, which is in accordance with a stepwise mechanism where formation of ...