Click chemistry in oleochemicals

2011 marked the fourth annual “Workshop on Fats and Oils as Renewable Feedstocks for the Chemical Industry”, held in Karlsruhe, Germany on March 20 – 22, 2011, by abiosus e.V., Non-Profit Association for the Advancement of Research on Renewable Raw Materials.

It has been a timely event reflecting the overall industrial trend to move from petrochemicals towards oleochemicals. The effort is to use renewable fat and oils as raw materials / platform chemicals and to use green and efficient processes in the manufacturing – where click chemistry is to lend a hand.

The champion is thiol-ene addition, initiated either by thermal or photochemical method. In the workshop multiple reports described use of thio-ene click chemistry to prepare monomers such as polyols for polyurethane. Also reported was the introduction of a large variety of functional groups to fatty acids for polyester and polyamides synthesis. Advantages were demonstrated: very high yield, undemanding conditions, insensitivity to oxygen inhibition, and ease of purification.

Application of thiol-ene addition in oleochemicals may present the best opportunity and first breakthrough for click chemistry to get into traditional on-scale chemical industry. Note that currently click chemistry is mostly used for discovery purposes, either in medicinal chemistry or materials science.