Cosmone®

Other comments :

Cosmone® can be used in very low quantity to bring an elegant effect.

Stability :

Stable in perfumes and in diverse functional bases, except in liquid bleach and candle bases.

Uses in perfumery :

Cosmone® is generally used as a nitromusk replacer. It has a quite similar effect and makes it possible to nuance base notes, thanks to its fruity and green facets.

Year of discovery :

Discovered in 1998

Isomerism :

Cosmone® has two diastereisomers, trans and cis. In perfumes, a blend of these two isomers is used, because they do not have a strong olfactive difference. Cosmone® is initially a blend of two positional isomers, called Cosmone® I and II. Both are obtained during the synthesis, and can be separated by distillation. Cosmone® is a constitutional isomer of some sandalwood alcohols as Javanol® or Polysantol®. Nevertheless, they do not have any olfactive similarities.

Synthesis precursor :

Cosmone® is not used for the synthesis of another molecule of olfactive interest.

Natural availability :

Cosmone® does not exist on a natural state. Thus, it can't be used as extracted from a plant.

Synthesis route :

Cosmone® is synthesized by a Wittig reaction in an alkaline medium, involving (4-carboxy-3-methylbutyl)triphenylphosphonium bromide and methyl 9-oxononanoate. This frist step leads to an ester, esterified using methanol (catalysor : paratoluensulfonic acid). Putting the ester in contact with pure sodium leads to a Bouveau-Blanc rearrangement, cycling the intermediary product into two acetates, linked by a positional isomery. To remove the ester groups from these two molecules, a reductive deacetoxylation is carried out with ammonia and calcium. This way, both Cosmone® isomers are obtained, to be separated by distillation.