Cross-metathesis approach to produce precursors of nylon 12 and nylon 13 from microalgae

A two-step synthesis for producing methyl 12-aminododecanoate and 13-aminotridecanoate, the precursors of nylon 12 and nylon 13, from methyl oleate is described. First, methyl 11-cyano-9-undecenoate or 12-cyano-9-dodecenoate were prepared by cross metathesis of methyl oleate with either allyl cyanide or homoallyl cyanide, respectively. Subsequently, all the unsaturation of the two intermediates was hydrogenated to deliver the final products. This method represents the first synthesis of nylon 12 and 13 precursors from methyl oleate, an ester of an abundant and renewable natural fatty acid present in vegetable oil or microalgae. It also represents the shortest synthesis of nylon precursors from fatty acids, and as demonstrated in this study, can be directly applied to crude fatty acid methyl ester extracts from microalgae.