1222-05-5

4,6,6,7,8,8-Hexamethyl-1,3,4,6,7,8-hexahydrocyclopenta[g]benzopyran is a viscous liquid with a musk-like odor. It is one of the most frequently used synthetic, artificial musk fragrances.The starting material for its synthesis is 1,1,2,3,3-pentamethylindane, which is prepared by cycloaddition of tert-amylene to α-methylstyrene. The pentamethylindane is hydroxyalkylated with propylene oxide in a Friedel–Crafts reaction using aluminum chloride as a catalyst (analogous to the synthesis of phenylethyl alcohol from benzene and ethylene oxide . Ring closure of the resulting 1,1,2,3,3-pentamethyl-5-(β-hydroxyisopropyl)indane is accomplished with paraformaldehyde and a lower aliphatic alcohol via the acetal or with paraformaldehyde and a carboxylic acid anhydride via the acylate.
The commercial product is diluted with solvents (e.g., diethyl phthalate, isopropyl myristate, benzyl benzoate) to make it less viscous. It is alkali-stable and does not discolor in light. Therefore, it is a popular ingredient of perfume compositions for soaps, detergents, and cosmetics and is used in large amounts.

Clear Colourless to Pale Yellow Oil

Galaxolide is a polycyclic musk (PCM) used as a fragrance ingredient in perfumes, soaps, cosmetics and detergents.

ChEBI: An organic heterotricyclic compound that is 1,3,4,6,7,8-hexahydrocyclopenta[g]isochromene substituted by methyl groups at positions 4, 6, 6, 7, 8 and 8 respectively. It is a synthetic musk used as a fragrance in cosmetics.

Notclassified

Galaxolide® (IFF), Astromusk (Agan),Musk YingHai (YingHai).

The synthesis of Galaxolide epimers proceeds via a catalytic route starting from pentamethylindane under mild conditions, featuring asymmetric hydrogenation as a key step[1]. The final stage involves reducing the derived acid to an alcohol, followed by ring closure with paraformaldehyde in the presence of sulfuric acid to yield the product in 78% yield[1].

[1]Ciappa, A., Matteoli, U., & Scrivanti, A. (2002). Asymmetric catalysis in fragrance chemistry: a new synthesis of Galaxolide. Tetrahedron: Asymmetry, 13(20), 2193–2195. https://doi.org/10.1016/s0957-4166(02)00538-4