Ambrettolide via Olefin Metathesis Under True High Concentration Conditions

This study describes the applications of molybdenum‐catalyzed homogeneous cross‐metathesis approaches, which led to the production of the unique macrocyclic musk lactone Ambrettolide under essentially solvent free conditions. Renewable octenyl decenoate 16 was pretreated to remove traces of water, oxygen, and peroxides and polymerized at low catalyst loadings to control the rate of ethylene evolution. In a subsequent intramolecular transesterification‐based depolymerization step, a new quality of Ambrettolide was obtained with an E/Z ratio of 85/15 and desired organoleptic properties, now available as AmbreXolide™.