%0 Journal Article
%T Kinetic Support for the Generation of a Phenylsulfenium Ion Intermediate
%A Hiroshi Takeuchi
%A Jun-ichi Tateiwa
%A Shintaro Moriguchi
%J Molecules
%D 2003
%I MDPI AG
%R 10.3390/80400392
%X In the reaction of N-methylbenzenesulfenamide (1) with thioanisole (4) in the presence of trifluoroacetic acid (TFA), the initial rate ¦Ô0 of total appearance of 2- and 4-(methylthio)phenyl phenyl sulfides (5) is first and zero order with respect to the initial concentrations of 1 and 4, respectively: ¦Ô0=kobs[1]0. The pseudo-first order rate constant kobs is evaluated as 5.2¡Á10-4 sec-1 with varying concentrations of 4 (0.72 to 5.0 M) in a mixture of 4 and CH2Cl2 in the presence of TFA at 10 ¡ãC. This data supports the notion that a phenylsulfenium ion intermediate 3 interacting with both the counter ion and the unshared electron-pair of amine is generated by heterolytic N-S scission of the protonated sulfenamide 2, leading to the observed formation of 5.
%K Phenylsulfenium ion intermediate
%K Kinetic study
%K Phenylthiolation
%K Sulfenamide
%K Thioanisole
%U http://www.mdpi.com/1420-3049/8/4/392