Synthesis of Long Chain Unsaturated‐α,ω‐Dicarboxylic Acids from Renewable Materials via Olefin Metathesis

The self‐metathesis reaction of soy, rapeseed, tall, and linseed oil fatty acids was investigated for the synthesis of symmetrical long‐chain unsaturated‐α,ω‐dicarboxylic acids. The metathesis reactions were carried out in the presence of a Grubbs catalyst under solvent‐free condition at a catalyst loading of 0.01 mol% to fatty acid substrate at 50 °C. Under these conditions, the conversions of starting unsaturated acids to metathesis products were >80% and the isolated yields of unsaturated dicarboxylic acid products were >70% of theoretical. This approach represents an effective and efficient route for the synthesis of these potentially useful dicarboxylic acids since they can serve as important intermediates in the production of several materials such as biodegradable polymers.