Cedarwood oils

Ced rwood. Many varieties of cedarwood oil are obtained from different parts of the world. They are produced mainly by steam distillation of chipped heartwood, but some are also produced by solvent extraction. The oils, which vary significantly ia chemical composition, are used ia perfumes as such, but the main uses are as distillation fractions and chemical derivatives. For the latter purposes the most used oils, which are similar ia composition, are from Texas ia the United States (Juniperus mexicand) and from China Cupressusfunebris). The principal constituents of these oils are cedrene [11028-42-5] (4), thujopsene [470-40-6] (5), and cedrol [77-53-2] (6). The first two of these are obtained together by distillation and used mostiy ia the form of acetylated derivatives. Cedrol is used as such and, to a greater extent, as its acetate ester. 

Many other compounds are presendy in use a 1993 database search showed 27 active ingredients in 212 products registered by the U.S. EPA for human use as repellents or feeding depressants, including octyl bicycloheptene dicarboxamide (A/-2-ethylhexylbicyclo[2.2.1]-5-hepten-2,3-dicarboxamide), dipropyl isocinchomeronate (2,5-pyridine dicarboxyhc acid, dipropyl ester), dimethyl phthalate, oil of citroneUa, cedarwood oil, pyrethrins, and pine tar oil (2). Repellent—toxicant or biting depressant systems are available which are reasonably comfortable for the user and can protect completely against a number of pests for an extended period of time (2). 

Important commercial sesquiterpenes mosdy come from essential oils, for example, cedrene and cedrol from cedarwood oil. Many sesquiterpene hydrocarbons and alcohols are important in perfumery as well as being raw materials for synthesis of new fragrance materials. There are probably over 3000 sesquiterpenes that have been isolated and identified in nature. 

Gedrene and Gedrol. Cedarwood oil is one of the essential oils whose production is large and provides a source for synthesizing a number of derivatives. Gedrene (91) and thujopsene (92) are the two main sesquiterpene hydrocarbons found in the oil, along with a number of minor components (187). Gedrol [77-53-2] (93) is the main alcohol component of the oil. 

Many cyclic sesquiterpene alcohols are key odor components in essential oils, for example, cedrol in cedarwood oil, the vetiverols in vetiver oil, and the santalols in sandalwood oil. Since these alcohols have not yet been synthesized on an industrial scale, they are described under the oil in which they occur (Chapter 3). Some of their derivatives, however, are discussed in this section. 

C17H26O, Mr 246.39, is a long-lasting wood fragrance which is prepared by acetylation of cedarwood oil fractions that contain sesquiterpene hydrocarbons, mainly a-cedrene and thujopsene. Acetylation is carried out in the presence of an acidic... 

Chinese cedarwood oil is similar in composition to Texas cedarwood oil (see below). Chinese cedarwood oil is obtained by steam distillation of Chamaecyparis funebris (Endl.) France (Cupressusfunebris Endl., Cupressaceae), which is a weeping cypress, indigenous to China. Commercial Chinese cedarwood oil is a colorless to slightly yellow oil with an odor more smoke-like than the American oils. 

Texas cedarwood oil is produced by steam distillation of chopped wood of the Texas cedar, Juniperus mexicana Schiede (Cupressaceae). It is a brown to reddish-brown, viscous liquid that may partially solidify at room temperature. It has a characteristic cedarwood odor. 

The price of Cedarwood oil from Texas in 1995 was 7.70/kg and the price of the oil from Virginia was 15.18/kg (69). Distillation of the oil gives two main fractions, the cedrene or hydrocarbon fraction, and the alcohol fraction consisting of impure cedrol, which when purified by crystallization can be used direcdy in perfumery. Cedrenol is a product comprising a mixture of cedrol and its isomers widdrol and some ketone components. 

Similar reflectances of some of the macerals (especially exinite and vitri-nite) in standard oil of n = 1.515 caused difficulties of positive identification. To circumvent this problem, an index oil adjusted to n = 1.60 was compounded from 1-bromonaphtnalene and cedarwood oil. The mixture provided sufficient differences in reflectivity between macerals for meaningful quantification. 

Ceclor [53994-73-3] Cedarleaf oils Cedar shakes Cedarwood oil... 

Cedarwood Oil, Copaiba Balsam Oil and Gurjun Balsam Oil.—These volatile oils lend themselves readily to the adulteration of many essential oils, owing to their cheapness and slight odour. 

Bergamot oil is adulterated in various ways, e.g., with oil of turpentine, oil or terpenes of lemon, orange terpenes, fatty oils, waxes, resin, gurjun and Canada balsam, cedarwood oil, mineral oils, chlorinated compounds of oil of turpentine, organic acids, various esters (diethyl succinate, triethyl citrate, diethyl oxalate, terpinyl acetate, esters of oleic, phthalic, tartaric and acetic acids). Such adulteration is usually made judiciously, the genuine oil being treated with such quantities of one or more picked adulterants as will not alter too markedly the characters of the oil itself.1... 

About 45 Terpenes, caproic esters, blue oil (azulene and ceru-lein) Cedarwood oil, oil of turpentine. 

Carvone (56%), terpenes, linalool Cedarwood oil, gurjun balsam oil... 

Sesquiterpenic alcohols used in perfumery are mainly of natural origin. Three alcohols of this type are shown in Figure 8. Cedrol is the main alcohol constituent of cedarwood oil. Alpha-santalol constitutes about 80% of sandalwood oil and about 30% patchouli alcohol is found in patchouli oil, a very popular woody-earthy fragrance material. 

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