Terpinen-4-ol

Other comments :

Terpinen-4-ol is a monoterpene. This means, as for D-Limonene, that this molecule is composed of two isoprene units, and therefor ten carbon atoms. This category of terpenes includes many isomer.

Stability :

Terpenes tend to polymerize under the effect of high oxydation, and are unstable in alkaline and acidic bases.

Uses in perfumery :

Terpinen-4-ol is used for aromatic accords, around pine, pepper and geranium, especially in detergents and functional perfumes. It brings an earthy effect.

Year of discovery :

Data not available.

Isomerism :

Terpinen-4-ol used in perfumery, and often found in nature, is a racemic mixture of its two enantiomers, dextrorotatory and levorotatory. Both have an equivalent odor, which explains the use of the mixture of the two isomers. Terpinen-4-ol is also a positional isomer of Alpha-Terpineol, which has a more floral and less earthy odor.

Synthesis precursor :

Terpinen-4-ol can be used for the synthesis of Alpha-Terpineol. The goal of this synthesis is to shift the alcohol function of the initial molecule to its neighbouring carbon. However, this synthesis is not very common.

Natural availability :

Terpinen-4-ol is present in many essential oils, especially aromatic ones. It is found in a large quantity in Marjoram EO and in Tea Tree EO. It is present in moderate quantities in Lavender EO, Nutmeg EO and Blackcurrant Bud Absolute.

Synthesis route :

Terpinen-4-ol is often synthesized at a low cost as a by-product in the synthesis of Alpha-Terpineol from Terpine hydrate. The resulting molecule is not completely pure. Nevertheless, it is possible to synthesize pure Terpinen-4-ol from Terpinolene by photosensitized oxidation, followed by reduction of the intermediary peroxide, and selective hydrogenation of the intermediate alcohol formed.