Regioselective Air Oxidation of Sulfides to<i>O,S</i>-Acetals in a Bubble Column
作者:Fabian Brockmeyer、Jürgen Martens
DOI:10.1002/cssc.201402310
日期:2014.9
In this paper the use of a bubblecolumn for a metal‐free, selective oxidation of α‐alkylthio‐imines to O,S‐acetals is presented. During the synthesis, which is straightforward to perform, the sulfides are oxidized to α‐alkoxy‐ or, respectively, α‐hydroxysulfide by adding activated carbon in the presence of atmospheric oxygen only. We show that the use of the bubblecolumn, which is unusual on laboratory
A hair relaxer includes at least one specific mercapto compound such as 2-methoxyethyl 3-mercaptopropionate, 2-mercapto-4-butanolide and 2-mercapto-4-butyrolactam. The hair relaxer can achieve an excellent effect of shaping and relaxing hair over a wide range of pH values from weak acidity to weak alkalinity. In particular, the hair relaxer displays a more superior hair shaping and relaxing performance in a weakly acidic to neutral pH range. Consequently, the hair relaxer can drastically reduce the damage to the hair and skin and can reliably perform straightening, uncurling, curling and other hair processing.
[EN] A hair relaxer includes at least one specific mercapto compound such as 2-methoxyethyl 3-mercaptopropionate, 2-mercapto-4-butanolide and 2-mercapto-4-butyrolactam. The hair relaxer can achieve an excellent effect of shaping and relaxing hair over a wide range of pH values from weak acidity to weak alkalinity. In particular, the hair relaxer displays a more superior hair shaping and relaxing performance in a weakly acidic to neutral pH range. Consequently, the hair relaxer can drastically reduce the damage to the hair and skin and can reliably perform straightening, uncurling, curling and other hair processing. [FR] L'invention porte sur un défrisant comprenant au moins un composé mercapto spécifique tel que le 2-méthoxyéthyl 3-mercaptopropionate, le 2-mercapto-4-butanolide et le 2-mercapto-4-butyrolactam. Ledit défrisant a un excellent effet de mise en forme et de défrisage pour une large plage de pH allant d'une faible acidité à une faible alcalinité, lesdites capacités s'avérant encore meilleures pour la plage allant d'un pH de faible acidité à un pH neutre. Par conséquent ledit défrisant réduit considérablement les dommages à la peau et aux cheveux, et peut de plus assurer fiablement le raidissement, le frisage, le défrisage et autres traitements du cheveu.
Asinger,F. et al., Justus Liebigs Annalen der Chemie, 1964, vol. 672, p. 103 - 133