Preparation of Musk-Smelling Macrocyclic Lactones from Biomass: Looking for the Optimal Substrate Combination.

Macrocyclic musk belongs to a well-known and valued class of the fragrance family. Originally, natural musks were obtained from rectal musk glands which often led to the death of the animals. Recently, a lot of effort was invested to obtain such macrocycles in a synthetic way. This research presents a study on the preparation of macrocyclic lactones with the musk scent by ring-closing metathesis (RCM) using biomass-derived starting materials: oleic and 9-decenoic acid. An experimental rule correlating the C-C double bond substitution pattern in the starting diene and the yield for the RCM macrocyclization was proposed.