Preparation of long‐chain fatty acid chlorides

Abstract

Summary A rapid method has been found for preparing the long‐chain fatty acid chlorides, which eliminates purification by distillation. It gave a quantitative yield of product containing less than 1.5% free acid. The method involves treating the free acid with phosphorus pentachloride or trichloride in an inert organic solvent and removing the excess chlorinating agent by washing the solvent phase with water. Phosphorus pentachloride and Skellysolve “F” were preferred for laboratory preparations. For commercial purposes however either chlorinating agent could be used in a variety of inert organic solvents. Infrared analysis was found to give a rapid measure of the free acid content of the prepared acid chlorides.