反应详情

Ingredients. (1) Water 97.5 (2) Resacetophenone 1.5 (3) Glycine 1.0. Procedure. The mixture of all ingredients is heated at 90 to 95 C for 2 hours. A solution of N-[(2,4-dihydroxyphenyl)ethylidene]glycine in water is obtained. It is then hydrogenated over Ni catalyst, filtered, and then acidified to pH 6.5. [RS]-N-[(2,4-dihydroxyphenyl)ethyl]glycine is thus obtained, which is then resolved into the corresponding [R] and [S] optical isomers. Both the [R,S] and [R] and [S] compounds thus obtained are esterified with methanol/thionyl chloride method to the corresponding methyl esters, which are used directly in cosmetic compositions of the present invention.

1. additionThe mixture of all ingredients
2. temperatureis heated at 90 to 95 C for 2 hours