[A study on the mechanism of reductive alkylation for preparing 3-(beta-hydroxy-ethyl-sulfonyl) N-ethyl aniline with HPLC/MS].
Hydrogenating 3-(beta-hydroxy-ethyl-sulfonyl)-aniline and acetaldehyde in the presence of Raney Nickel as a catalyst, 3-(beta-hydroxy-ethyl-sulfonyl)-N-ethyl-aniline was obtained with 98% conversion and 95% monoalkylation selectivity under optimum conditions. By using high performance liquid chromatography/mass selective detection technique to characterize the structures of the products, the mechanism of reductive alkylation is proposed. From the intermediates determined, it is shown that the reaction mechanism would go via an unstable N-alpha-hydroxyethylaniline derivative and Schiff base stage. After hydrogenation of Schiff base, finally the product 3-(beta-hydroxyethyl-sulfonyl)-N-ethyl aniline was formed.
Zhang
R
R
State Key Laboratory of Dye and Surfactant Fine Chemicals, Dalian University of Technology, Dalian 116012, China.
Wu
Z W
ZW
Lin
L S
LS
Yang
H Y
HY