Synthesis of fatty acid amides, fatty acid esters and their derivatives using halogenating agents and triphenylphosphine

Abstract

The methodology for the synthesis of fatty acid amides, fatty acid esters and their derivatives utilizing halogenating agents and PPh3 was developed. Trichloroacetamide coupled with PPh3 was found to be an effective system for this kind of conversion. To optimize the reaction conditions, type of halogenating agents and PPh3, reaction time and temperature were investigated. Polystyrene-supported PPh3 was used in this reaction to simplify the purification of the product. The optimum condition for the fatty acid chloride preparation step and the nucleophilic attack step were achieved when refluxed both steps in CH2Cl2 for 30 min each. The use of polystyrene-supported PPh3 also gave a comparable yield to that of PPh3. This methodology was applied to synthesize aromatic, short chain and long chain aliphatic fatty acid amides and esters. Furthermore, the developed methodology for the preparation of fatty acid derivatives including fatty acid thioesters and fatty acid anhydrides was successfully achieved.