Use of N-chloro-N-methyl-p-toluenesulfonamide in N-chlorination reactions

Abstract

Second-order rate constants (k 2 ) were determined for the addition of ten nitrogenous organic compounds (benzylamine, 2,2,2-trifluoethylamine chlorhidrate, methylamine chlorhidrate, glycine ethyl ester chlorhidrate, glycine, glycylglycine chlorhidrate, morpholine, pyperidine, pyperazine and dimethylamine) to the N-chloro-Nmethyl-p-toluenesulfonamide (NCNMPT) in the formation reaction of N-chloramines in aqueous solution at 25 C and ionic strength 0.5 M. The series of nucleophiles considered is structurally very varied and covers five pK a units.The kinetic behaviour is similar for all compounds, being the elementary step the transfer of chlorine from the NCNMPT molecule to the nitrogen of the free amino group. These reactions were found first order in both reagents. The values of the rate constants indicate that the more basic amines produce N-chloramines more readily.Rate constants for the nucleophilic attack are shown to correlate with literature data for some of these nitrogenous organic compounds in their reaction with N-methyl-N-nitroso-p-toluenesulfonamide. Both reactions involve that the rate determining step is the attack of nitrogenous compounds upon electrophilic centre (Cl or else NO group).NCNMPT is a particularly interesting substrate, for which has not hitherto been published kinetic information, that allows us to assess the efficiency and the competitiveness of this reaction and compare it with other agents with a Cl + atom. a calculated from empirical equations of Hall for primary and secondary amines. b calculated by extrapolation of the linear correlation between N + and n, considering N + = 4.40.

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

“…Also, they allow us to establish structure–reactivity relationships, comparing the results obtained in this work with bibliographic results. On the other hand, we have at our disposal information regarding the kinetic studies of these amines with other chlorinating agents (HOCl, N ‐chloro‐ N ‐methyl‐ p ‐toluenesulfonamide), so it is also interesting to compare the effectiveness of the different N ‐chlorinating agents because of the great importance of these N ‐chlorination reactions in environmental and biochemical processes …”

“…On the other hand, we have at our disposal information regarding the kinetic studies of these amines with other chlorinating agents (HOCl, N-chloro-N-methylp-toluenesulfonamide), so it is also interesting to compare the effectiveness of the different N-chlorinating agents because of the great importance of these N-chlorination reactions in environmental and biochemical processes. [24][25][26][27][28][29][30]…”

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 …”

Mechanism for the reactions of sulfides with hypochlorous acid and N‐chlorosulfon‐amides: Formation of solvated chlorosulfonium cation and λ4‐sulfane intermediates

“…N ‐chloroamides are widely used chlorinating agents; the chlorine transfer reactions to sulfides and amines have been thoroughly investigated. The chlorine potential of N ‐chlorosulfonamides increases with the increasing acidity of the protons of parent amides (MsNH − << MsNH 2 < < MsNHCl) .…”

“…Therefore, one can conclude that, in contrast with the reactions of sulfides with HOCl, [25] the reactions of sulfides with N-chlorosulfonamides do not proceed with the S N 2 mechanism, presented on Scheme 4. N-chloroamides are widely used chlorinating agents [11,35,36] ; the chlorine transfer reactions to sulfides [1,[9][10][11][12][13][14] and amines [37][38][39][40] have been thoroughly investigated. The chlorine potential of N-chlorosulfonamides increases with the increasing acidity of the protons of parent amides (MsNH − << MsNH 2 < < MsNHCl).…”