Insights into gold-catalyzed synthesis of azelaic acid

Abstract

A novel green route for the synthesis of azelaic and pelargonic acid via aerobic gold-catalyzed cleavage of 9,10-dihydroxystearic acid (DSA) was investigated recently. In this study, the examination of the reaction mechanism is described. The results of the application of ¹⁸O-labeled molecular oxygen and sodium hydroxide as well as of diastereomeric pure erythro- and threo-DSA were discussed. Assumed reaction intermediates were synthesized and subjected to the same reaction conditions as with DSA. As a conclusion from the obtained data, an oxidative dehydrogenation mechanism was postulated. Additionally, the aging of the gold catalyst used under different storage conditions was explored.