3,3-Dimethyl-5-(2,2,3-trimethyl-3-cyclopenten-1-yl)-4-penten-2-ol

3,3-Dimethyl-5-(2,2,3-trimethyl-3-cyclopenten-1-yl)-4-penten-2-ol is not found in nature. It is a clear, colorless liquid, d25 25 0.897–0.906, n20 D 1.480–1.484, with a powerful, diffusive sandalwood odor and musk and cedarwood aspects. The compound is prepared starting from α-campholenaldehyde, which is condensed with 2-butanone to give 3-methyl- 5-(2,2,3-trimethyl-3-cyclopenten-l-yl)-3-penten-2-one. Methylation using phase-transfer conditions gives the dimethylpentenone, which is reduced with NaBH₄ to yield the title compound. It is used in fine fragrances.

Polysantol® (Firmenich)