Muscone
Muscone is a macrocyclic ketone, an organic compound that is the primary contributor to the odor of deer musk. Natural muscone is obtained from musk, a glandular secretion of the musk deer, which has been used in perfumery and medicine for thousands of years. Since obtaining natural musk requires killing the endangered animal, nearly all muscone used in perfumery and for scenting consumer products today is synthetic. It has the characteristic smell of being "musky".
Chemical structure and synthesis
The chemical structure of muscone was first elucidated by Leopold Ružička. It is a 15-membered ring ketone with one methyl substituent in the 3-position. It is an oily liquid that is found naturally as the -enantiomer, -3-methylcyclopentadecanone. Muscone has been synthesized as the pure -enantiomer as well as the racemate. It is very slightly soluble in water and miscible with alcohol.One asymmetric synthesis of -muscone begins with commercially available -citronellal, and forms the 15-membered ring via ring-closing metathesis:
A more recent enantioselective synthesis involves an intramolecular aldol addition/dehydration reaction of a macrocyclic diketone.