Undecylenic acid : a valuable and physiologically active renewable building block from castor oil

Nowadays a lot of attention is paid to the transition to a bio-based economy.[1] In this movement, most efforts concentrate on the development of bio-energy applications including bio-ethanol, biodiesel, thermochemical conversion of biomass, … However, in the energy sector other non-biomass alternatives are known, whereas no valuable alternatives are available when thinking about chemical building blocks. Therefore, it is also essential to develop new routes for the synthesis of bio-based chemicals and materials derived thereof. Such intermediates can originate either from plants or from animals. Castor oil is a non-edible oil extracted from the seeds of the castor bean plant Ricinus communis (Euphorbiaceae), which grows in tropical and subtropical areas. Globally, around one million tons of castor seeds are produced every year, the leading producing areas being India, China and Brazil.[2] 10-Undecenoic acid or undecylenic acid (further called UA) is a fatty acid derived from castor oil that, due to its bifunctional nature, has many possibilities to develop sustainable applications