Kinetic study of the formation of N‐chloro compounds using N‐chlorosuccinimide

Abstract

b Second-order rate constants were determined for the chlorination reaction of 2,2,2-trifluoethylamine and benzylamine with N-chlorosuccinimide at 25°C and an ionic strength of 0.5 M. These reactions were found to be of first order in both reagents. According to the experimental results, a mechanism reaction was proposed in which a chlorine atom is transferred between both nitrogenous compounds. Kinetics studies demonstrate that the hydrolysis process of the chlorinating agent does not interfere in the chlorination process, under the experimental conditions used in the present work. Free-energy relationships were established using the results obtained in the present work and others available in the literature for chlorination reactions with N-chlorosuccinimide, being the pK a range included between 5.7 and 11.22.

Kinetic study of the formation reaction of N-chloro-2-oxazolidinone

“…In the present work, the rate constants obtained for the reactions of OXA with HOCl and t BuOCl were similar and higher than the rate constants obtained in the reaction with NCS. These values follow the same trend as those found with other nitrogenous compounds …”

“…The values for the activation energy obtained in this work were compared with others obtained under similar conditions, which were found in the literature. It was found that they are of the same order of magnitude as those obtained for the reaction of this nitrogenous compound with its analogous N ‐brominating agent (NBS), and with those obtained for the N ‐chlorination reaction of the nitrogenous compound with these chlorinating agents (HOCl, t BuOCl, and NCS) …”

“…In order to justify the reaction mechanism for the OXA reaction with NCS, it is necessary to consider the information found in the literature on N ‐chlorination reactions of nitrogenous compounds with NCS …”

“…To do this, we have considered the pK a value for the OXA calculated in the reaction of this nitrogenous compound with HOCl. In addition, under these pH conditions, the available literature regarding to NCS in solution indicates that K 1 > [H + ] …”

Reactions of chlorination withtert-butyl hypochlorite (TBuOCl)

“…Moreover, these relationships could also be used to predict the behavior of other nitrogenous compound similar. Also, the effectiveness of the different N ‐chlorinating agents is interesting to compare because of the great importance of these N ‐chlorination reactions in environmental and biochemical processes …”