Lewis acid catalyzed cis (liquid) to trans (solid) isomerization of Jojoba oil in supercritical CO2

Abstract

Isomerization of the olefin from cis to trans configuration is often a desirable reaction pathway that leads to products with different properties and chemical reactivities. In this work, we report a novel process involving the use of boron trifluoride diethyl etherate, BF3·O(C2H5)2, in supercritical CO2 that converts a compound with an isolated cis to a trans olefin in quantitative yield. No polymerization was observed. The utility of this reaction has been demonstrated by the conversion of jojoba oil (a natural wax ester, comprising a monoester of long-chain fatty acids with cis olefins) to its trans isomers. Jojoba oil is liquid at room temperature with a melting point of about 10 °C; the reacted product is a solid with a melting point of 37.6 °C (around the normal human body temperature). The simplicity of the reaction and the use of supercritical CO2 are the attractive features of this reaction.