Terpinyl acetate

The increase in values by prolctigiug the time of sapouifioatiaii is a strong indication ot terpinyl acetate, whieh is. as is well known, an ester much more resistant lo the action of alcoholic pota-sh than linalvl acetate. 

Fractional saponific alkali, will also reveal 1 The followinp table ition, with the use of varyieg amc c presence of terpinyl acetate, will indicate the differences observ d when about... 

Terpinyl Acetate.—The acetic acid ester of terpipeol is also a natural ester. It nas a refreshing odour, and is often described as being a bergamot and lavender substitute. The writer, however, considers this description unjustifiable, and that it is really due to the fact that it is so often used and recommended as an adulterant for these two essential oils. Terpinyl acetate isia colourless oil, of the formula... 

It is soluble in about 5 volumes of 70 per cent, alcohol. This ester has the character of being saponified much more slowly than most other esters, so that in any determination in which it is involved it is necessary to saponify the sample for two hours before it is safe to consider the reaction complete. This fact also assists in determining whether terpinyl acetate is present as an adulterant in natural essential oils, for if the saponification value as determined by thirty minutes saponification is materially lower than that as determined by a two hours saponification, it may be fairly safely inferred that terpinyl acetate or some similar ester is present. 

Terpinyl acetate in the absence of esters of high molecular weight, or ethyl esters of the fatty acids of coconut oil, is indicated by a difference to be observed in the apparent ester value by different times of saponification. This ester is far more resistant to the action of caustic alkali than is linalyl acetate, and requires two hours at least for complete saponification. Hence, if the oil shows a difference in the saponification value in thirty minutes and in two hours, which amounts to more than from 1 to 2, terpinyl acetate is almost certainly present. The following table shows the effect of this partial-saponrfication on the two esters and on adulterated oils —... 

The table on next page represents the behaviour on fractionation at 3 mm. pressure of two samples of bergamot adulterated with terpinyl acetate and a sample of pure bergamot oil. 

All these were adulterated with ethyl citrate except Nos. 3 and 7, which contained terpinyl acetate, and No. 9, which was adulterated... 

It is evident that, in order to obtain accurate results, the method of working must be clearly and minutely adhered to, especially so in view of the fact that the determination of ester by the method of steam distillation is a very valuable indication as to the purity of an oil, serving to detect the fraudulent addition to oils of such esters as diethyl succinate, triethyl citrate, and diethyl oxalate, the free acids of which are nonvolatile in steam. It will not detect glyceryl acetate, terpinyl acetate, nor the esters of coconut oil fatty acids. 

Terpenoid pheromones, 24 473 Terpenoid skeletons, 24 469 biosynthesis of, 24 471 Terpin hydrate, 3 231 a-Terpineol, 24 477, 509-512, 3 231 hydrogenation of, 24 512 a-Terpinyl acetate, 24 512 a-Terpinyl chlorides, 24 479 a-Terpinyl esters, 3 231 y-Terpinene, 3 230 Terpinolene, 24 493 Terpolymers... 

Heteropoly acids such as H3PW12O40 (PW) are good catalysts for the hydration of limonene and other monoterpenes. PWs can be used as homogeneous catalysts in solution or supported on, for example, silica or MCM-41 materials. In aqueous acetic acid limonene gives, in the presence of PW, mainly a-terpineol (7) and a-terpinyl acetate (8) [17]. 

SCHEME 56. Na -directing regioselectivity and diastereoselection in the intrazeolite photooxygenation of a-terpinyl acetate... 

Because of its odor properties, stability, and low price, large quantities of terpinyl acetate are used in perfumery for lavender and bergamot types, as well as in essential oil reconstitutions. 

The major components of cardamom oil are 1,8-cineole and a-terpinyl acetate (ca. 30% each). Trace constituents like unsaturated aliphatic aldehydes may be important for the typical aroma [301-307b]. It is produced from cultivated or wild plants in the mountainous regions of southern India, Sri Lanka, Indonesia, and Guatemala. 

The main constituent of the leaf oil is a-terpinyl acetate, while the main constituent and odor-determining component of the root oil is ligustilide [4431-01-0] (3-butylidene-4,5-dihydrophthalide) [609-612a]. 

Cardamom Elettaria cardamo-mum Maton a-Terpinyl acetate (30), 1,8-cineole (30)... 

Cardamom oil 1,8-Cineol, a-terpinyl acetate Baked products... 

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