Terpineol

alpha-Terpineol
IUPAC name 2-(4-Methyl- 1-cyclohex- 3-enyl) propan- 2-ol
Other names alpha-Terpineol α-Terpineol p-Menth- 1-en-8-ol α,α,4- Trimethylcyclohex- 3-ene- 1-methanol Terpene alcohol
Identifiers
CAS number	98-55-5 Y
ChemSpider	13850142 Y
UNII	21334LVV8W Y
ChEBI	CHEBI:22469 N
ChEMBL	CHEMBL507795 N
Jmol-3D images	Image 1
SMILES C\C1=C\CC(CC1)C(O)(C)C
InChI InChI=1S/C10H18O/c1-8-4-6-9(7-5-8)10(2,3)11/h4,9,11H,5-7H2,1-3H3 Y Key: WUOACPNHFRMFPN-UHFFFAOYSA-N Y InChI=1/C10H18O/c1-8-4-6-9(7-5-8)10(2,3)11/h4,9,11H,5-7H2,1-3H3 Key: WUOACPNHFRMFPN-UHFFFAOYAL
Properties
Molecular formula	C10H18O
Molar mass	154.25 g/mol
Density	0.9338 g/cm3
Melting point	18 °C
Boiling point	219 °C 81-82 °C at 4.5 mmHg
Hazards
MSDS	External MSDS
NFPA 704	1 2 0
N (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Terpineol is a naturally occurring monoterpene alcohol that has been isolated from a variety of sources such as cajuput oil, pine oil, and petitgrain oil^[1]. There are three isomers, alpha-, beta-, and gamma-terpineol, the last two differing only by the location of the double bond. Terpineol is usually a mixture of these isomers with alpha-terpineol as the major constituent.

Terpineol has a pleasant odor similar to lilac and is a common ingredient in perfumes, cosmetics, and flavors. α-terpineol is one of the two most abundant aroma constituents of lapsang souchong tea; the α-terpineol originates in the pine smoke used to dry the tea.^[2]

Although it is naturally occurring, terpineol is commonly manufactured from the more readily available alpha-pinene.

In one study, an alternative route starting from d-limonene was demonstrated^[3]:

Limonene is reacted with trifluoroacetic acid in a Markovnikov addition to a trifluoro acetate intermediate, which is easily hydrolyzed with sodium hydroxide to α-terpineol with 76% selectivity. Side-products are the β-terpineol in a mixture of cis-isomer and trans isomer and 4-terpineol.

References

1. ^ Merck Index, 11th Edition, 9103.
2. ^ Shan-Shan Yao； Wen-Fei Guo； YI Lu； Yuan-Xun Jiang, "Flavor Characteristics of Lapsang Souchong and Smoked Lapsang Souchong,a Special Chinese Black Tea with Pine Smoking Process", Journal of Agricultural and Food Chemistry, Vol. 53, No.22, (2005)
3. ^ A Practical Synthesis of d--Terpineol via Markovnikov Addition of d-Limonene Using Trifluoroacetic Acid Yoshifumi Yuasa and Yoko Yuasa Org. Process Res. Dev.; 2006; 10(6) pp 1231 - 1232; (Article) doi:10.1021/op068012d

External links

• MSDS for alpha-terpineol
• http://commons.wikimedia.org/wiki/Gallery_Terpenes