Applications of phase‐transfer catalytic reactions to fatty acids and their derivatives: Present state and future potential

Abstract

AbstractPhase‐transfer catalysts (PTC), which accelerate reactions between liquid(organic)‐liquid(water) and liquidsolid heterogeneous states, have been investigated and developed. Several processes with PTC have succeeded in industrial processes involving fatty acids and their derivatives. For example, preparation of fatty alkyl glycidyl ethers, from which fatty alkyl glyceryl ethers and their derivatives can be obtained, has been carried out with PTC. However, some problems remain to be solved. For example, preparation of the fatty alkyl glycidyl ether by a PTC reaction was considered, but typical problems to be solved included: (i) how to reuse or recover the catalysts; (ii) how to control the heterogeneous reaction without obstacles to produce useful chemical materials; (iii) how to satisfy the environmental requirements for the catalysts; and (iv) are there more effective catalysts? We address these problems based on our own experiences with phase‐transfer catalytic Williamson ether syntheses of fatty alkyl glycidyl ethers. Moreover, we describe recent developments in phase‐transfer catalytic reactions related to oleochemistry, such as transition metal‐catalyzed reactions of long‐chain olefins in liquid(organic)‐liquid(water) or liquid‐solid heterogeneous states. Based on these results, we have considered the potential of PTC as a synthetic tool in oleochemistry.