Oc-Terpineol

Terpenes are characterized as being made up of units of isoprene in a head-to-tail orientation. This isoprene concept, invented to aid in the structure determination of terpenes found in natural products, was especially useful for elucidation of structures of more complex sesquiterpenes, diterpenes, and polyterpenes. The hydrocarbon, myrcene, and the terpene alcohol, OC-terpineol, can be considered as being made up of two isoprene units in such a head-to-tail orientation (1). 

Pine oils can be fractionally distilled to produce a higher OC-terpineol product, but usually contain bomeol and y-terpineol, along with small amounts of other components. High grade perfumery OC-terpineol can be made by the partial dehydration ofy>-menthane-l,8-diol (terpin hydrate) under mildly acidic... 

OC-Terpineol (9) can be readily acetylated to its acetate using acetic anhydride (119). Ot-Terpinyl acetate [80-26-2] has a sweet, herbaceous, refreshing odor of the beigamot-lavender type and is used in scenting soaps and other household products such as cleansers and polishes. The selling price of terpinyl acetate in 1995 was 3.96/kg (45). 

Hydrogenation of OC-terpineol gives dihydroterpineol [498-81-7], a mixture of cis- and trans-compounds (120). Dihydroterpinyl acetate [80-25-1] produced from the mixture is also a useful fragrance compound. 

Terpin n. Terpinol, 4-hydroxy-a,a,4-tri-methylcyclohexanemethanol. Additional names p-menthane-l,8-diol dipentenegly-col. Molecular formula C10H20O2. Molecular weight 172.26. Percent composition C 69.72%, H 11.70%, O 18.58%. Literature references from Merck Index, 13th edn. 2001 Both cis-and trans-modifications are known. The ds-compound is obtained most readily in the hydrated form, cis-terpin hydrate. Prepn of ds-form from oil of turpentine Hempel, Ann. 180, 71 (1876) Wallach, Ann. 230, 225 (1885) Schmitt, Mfg. Chemist 26, 350 (1955). From d-limonene Sword, /. Chem. Soc. 127y 1632 (1925). Prepn of trans-form from 1,8-cineole, oc-terpineol or ds-terpin hydrate. Matsuura et al. (1958) Bull Chem Soc Japan 31, 990. Lombard, Ambroise, Bull... 

FIGURE 14.169 Biotransformation of (-)-myrtenol (S ) and (-)-oc-terpineol (34 ) by Aspergillus niger TBUYN-2. (Modified from Noma, Y. and Y. Asakawa, 2005b. Proc. 49th TEAC, pp. 78-80.)... 

A method employing a similar effect is that of Windaus, Weinhold, and Klanhardt,87 who found that digitonin precipitates the digitonide of one (partially) active form of a-terpineol and oc-tetrahydro-/3-naphthol when added to a solution of the racemic form. The method failed with dt-carvomenthol and eM-methylphenylcarbinol and with the majority of... 

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