3D model (JSmol)
|Molar mass||154.253 g·mol−1|
|Melting point||−35.9 to −28.2 °C (−32.6 to −18.8 °F; 237.2 to 245.0 K) (mixture of isomers)|
|Boiling point||214–217 °C (417–423 °F; 487–490 K) (mixture of isomers)|
|Safety data sheet||External MSDS|
|NFPA 704 (fire diamond)|
|Flash point||88 °C (190 °F; 361 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Terpineol is any of four isomeric monoterpenoids. Terpenoids are terpene that are modified by the addition of a functional group, in this case, an alcohol. Terpineols have been isolated from a variety of sources such as cardamom, cajuput oil, pine oil, and petitgrain oil. Four isomers exist: α-, β-, γ-terpineol, and terpinen-4-ol. β- and γ-terpineol differ only by the location of the double bond. Terpineol is usually a mixture of these isomers with α-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. (+)-α-terpineol is a chemical constituent of skullcap.
Synthesis and biosynthesis
Limonene reacts with trifluoroacetic acid in a Markovnikov addition to a trifluoroacetate intermediate, which is easily hydrolyzed with sodium hydroxide to α-terpineol with 7% selectivity. Side-products are β-terpineol in a mixture of the cis isomer, the trans isomer, and 4-terpineol.
The biosynthesis of α-terpineol proceeds from geranyl pyrophosphate, which releases pyrophosphate to give the terpinyl cation. This carbocation is the precursor to many terpenes and terpenoids. Its hydrolysis gives terpineol.
- Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
- Merck Index, 11th Edition, 9103
- Shan-Shan Yao; Wen-Fei Guo; Yi Lu; Yuan-Xun Jiang (2005). "Flavor Characteristics of Lapsang Souchong and Smoked Lapsang Souchong, a Special Chinese Black Tea with Pine Smoking Process". Journal of Agricultural and Food Chemistry. 53 (22): 8688–93. doi:10.1021/jf058059i. PMID 16248572.
- Yuasa, Yoshifumi; Yuasa, Yoko (2006). "A Practical Synthesis of d-α-Terpineol via Markovnikov Addition of d-limonene Using Trifluoroacetic Acid". Organic Process Research & Development. 10 (6): 1231–1232. doi:10.1021/op068012d.
- Davis, Edward M.; Croteau, Rodney (2000). "Cyclization enzymes in the biosynthesis of monoterpenes, sesquiterpenes, and diterpenes". Biosynthesis. Topics in Current Chemistry. 209. pp. 53–95. doi:10.1007/3-540-48146-X_2. ISBN 978-3-540-66573-1.CS1 maint: uses authors parameter (link)