Campholenic aldehyde is a monoterpenoid aldehyde derived from α-pinene. It is a colorless to pale yellow liquid with a characteristic woody, amber-like odor. Its structure features a cyclopentane ring fused to a cyclohexane ring, with an aldehyde group and an exocyclic double bond, making it a versatile chiral building block. The primary industrial application of campholenic aldehyde is as a key intermediate in the synthesis of high-value fragrance ingredients. It is most notably used in the production of Sandalore® (2-ethyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)but-2-en-1-ol), a widely used sandalwood odorant in perfumery and cosmetic formulations. Its rigid, chiral structure also makes it a valuable starting material for the synthesis of other specialty chemicals, including certain dyes and functional materials that require specific steric and electronic properties. As a fragrance intermediate and a chiral synthon, campholenic aldehyde is handled as a chemical substance requiring standard safety precautions. It should be stored in a cool, well-ventilated area away from strong oxidizers.