Linalyl alcohol

Linalool, 3 231, 232, 233 24 477, 495, 496, 500-503, 546 acid treatment of, 24 502 epoxidation of, 24 502 main producers of, 24 501 Linalool oxide, 24 502 Linalyl, 24 479 Linalyl acetate, 24 501 Linalyl alcohol, 24 500 Linalyl esters, 3 231 Linalyl oxide, 24 503 Lincomycin, registered for use in aquaculture in Japan, 3 221t Lincosamide, bacterial resistance mechanisms, 3 32t Lindane, 13 145-147... 

Synonyms 2,6-Dimethyl-2,7-octadien-6-ol 3,7-Dimethyl-1,6-octadien-3-ol Licareol Linalol Linalyl alcohol... 

Linalyl Acetate Extra. See Linalyl acetate Linalyl alcohol. See Linalool Linalyl 2-ami nobenzoate Linalyl o-aminobenzoate. See Linalyl anthranilate Linalyl anthranilate... 

Many monoterpenes have been used for anthelminthics. Among these are sabinol, cadinol (a sesquiterpene), pinene, ascaridole (87), p-cymene (81), citronellol (7), caryophyllene (a sesquiterpene), limonene (11), phellandrene, cadi-nene (a sesquiterpene), camphor (33), pyrethiin, carvone (48), linalool (6), linalyl alcohol, tagetone, thymol (88), and 1,8-cineole (eucalyptol) (10). 

Linalool (23) is more properly spelt linalool and pronounced with two distinct o sounds, the first long and the second short. This gives an indication of one of its principal sources, Linaloe oil, the essential oil of the Indian tree Bursera delpechiana, which contains levels of 30% linalool and 45-50% of its acetate. However, it is common practice nowadays to omit the diaeresis and even to speU the name with a single letter o. Other synonyms include linalyl alcohol, Licareol (extract from rosewood), and Coriandrol (extract from coriander). It occurs very widely in nature. The richest source is Ho leaf oil from China and Taiwan, which typically contains >90% linalool and levels as high as 97.5%, have been reported (150). Rosewood oil will typically contain 75-85% linalool and it is a major component of many flower (e.g., 80% in Ifeesia and 75% in honeysuckle) and herb (e.g., 65-80% in coriander) oils. Linalyl acetate is also a frequently encountered component of plant oils. Oils in which it plays a particularly important organoleptic role, include lavender ( 50%) and citrus leaf oils (also 50%). 

Aroma chemicals are isolates, or chemically treated oils or components of oils. Some components are removed physically, others chemically. In most cases, they are further purified by distillation. For example, Bois de Rose (rosewood) oil may be distilled to isolate linalool, which may be then further treated chemically to yield derivatives such as linalyl acetate, an important fragrance ingredient and a primary component in its own right of lavender and lavandin oils. Vetiver oil Haiti, although containing only 70% alcohols, is treated with acetic anhydride, then carefully distilled to include valuable odor components in the distillate, even though they may not be esters. 

The acetates of most alcohols are also commercially available and have diverse uses. Because of their high solvent power, ethyl, isopropyl, butyl, isobutyl, amyl, and isoamyl acetates are used in ceUulose nitrate and other lacquer-type coatings (see Cellulose, esters). Butyl and hexyl acetates are exceUent solvents for polyurethane coating systems (see Coatings Urethane polymers). Ethyl, isobutyl, amyl, and isoamyl acetates are frequentiy used as components in flavoring (see Flavors and spices), and isopropyl, benzyl, octyl, geranyl, linalyl, and methyl acetates are important additives in perfumes (qv). 

Mondello et al. (2, 20-23) have used a multidimensional gas chromatographic system based on the use of mechanical valves which were stable at high temperatures developed in their laboratory for the determination of the enantiomeric distribution of monoterpene hydrocarbons (/3-pinene, sabinene and limonene) and monoterpene alcohols (linalol, terpinen-4-ol and a-terpineol) of citrus oils (lemon, mandarin, lime and bergamot). Linalyl acetate was also studied in bergamot oil. The system consisted of two Shimadzu Model 17 gas chromatographs, a six-port two-position valve and a hot transfer line. The system made it possible to carry out fully... 

L. Mondello, A. Verzera, P. Previti, F. Crispo and G. Dugo, Multidimensional capillar y GC-GC for the analysis of real complex samples. Part V. Enantiomeric distribution of monoterpene hydrocarbons, monoterpene alcohols and linalyl acetate of bergamot (Citrus bergamia Risso et Poiteau) oils , 7. Agric. Food Chem. 46 4275-4282 (1998). 

The oil was found to conlain about 6 per cent, of piuene, 60 per cent-Of euoalyptol, 9 per cent, of borneol, 19 per ceul. of linalyl acetate, with a little camphor, meth. i salicylate, and sesqnitci-pene alcohol. 

The fact that the amount of total linalol decreases whilst the richness in linalyl acetate increases, proves that linalol appears in the plant at an earlier period than its acetic ester. Further, the free acetic acid acting on the linalol esterifies a portion of it, whilst another portion of this terpene alcohol is dehydrated, with the production of limonene and. dipentene, which are the usual resultants of linalol in presence of certain dehydrating agents. This view is corroborated by the fact that the quantity of the mixed terpenes increases during the esterification, without the slightest variation being observed in the ratio between the... 

Geraniol is converted into the isomeric alcohol, linalol, hy heat, and both alcohols yield the same chloride when treated wijth dry hydrochloric acid gas. Dupont and Labaune first prepared this chloride, which they considered was linalyl chloride, but Eorster and Cardwell have shown that it is geranyl chloride. 

Linalyl Propionate.—This ester is also produced by condensing the free alcohol and the free acid by means of sulphuric acid. It has a somewhat fruity odour recalling that of bergamot, and is especially suitable for perfumes of the lily of the valley type. It is a colourless oil, boiling at 115° at 10 mm. pressure. 

Linalyl Butyrate.—The butyric ester of linalol has the formula, CiflHjjOOC, CH2. CHjCHj. It resembles geranyl butyrate in odour, but is somewhat heavier. It is most useful for imparting fruity odours to flower perfumes. It is prepared by condensing the alcohol and the acid by means of sulphuric acid. 

Esters, or salts of alkyl radicles, such as linalyl acetate, etc., are frequently the most important constituents of essential oils. Their importance is especially noteworthy in such cases as lavender , bergamot, peppermint, and wintergreen oils, and their estimation is very frequently necessary. The principle upon which this depends is the fact that most esters are decomposed by solution of caustic alkali (preferably in alcohol) according to the equation—... 

Weinreich B, Nitz S, Influences of processing on the enantiomeric distribution of chiral flavour compounds, Part A Linalyl acetate and terpene alcohols, Chem MikrobiolTechnol Lebensm 14 117—124, 1992. 

Treatment of the selenide (19) with unbuffered 30% hydrogen peroxide-THF yields the cis- and trans-linalyl oxides (247) via [2,3] sigmatropic rearrangement. Kossanyi et al. have improved upon the efficiency of Vig s synthesis of the four lilac alcohols (248). The synthesis of the furanoid (249), formed during sulphuric acid-catalysed dimerization of isoprene, is straightforward. The known half-... 

A considerable portion of commercially available geraniol is produced by a modified process linalool obtained in a purity of ca. 65% from a-pinene is converted into linalyl borates, which rearrange in the presence of vanadates as catalysts to give geranyl and neryl borates. The alcohols are obtained by hydrolysis of the esters [32]. 

Esterification of linalool requires special reaction conditions since it tends to undergo dehydration and cyclization because it is an unsaturated tertiary alcohol. These reactions can be avoided as follows esterification with ketene in the presence of an acidic esterification catalyst below 30 °C results in formation of linalyl acetate without any byproducts [71]. Esterification can be achieved in good yield, with boiling acetic anhydride, whereby the acetic acid is distilled off as it is formed a large excess of acetic anhydride must be maintained by continuous addition of anhydride to the still vessel [34]. Highly pure linalyl acetate can be obtained by transesterification of tert-butyl acetate with linalool in the presence of sodium methylate and by continuous removal of the tert-butanol formed in the process [72]. 

In addition to linalyl acetate, the oil contains linalool and other terpene alcohols, as well as their acetates. When the volatile components are evaporated, a distinct ambergris note develops that is attributed to oxidative degradation products of sclareol [515-03-7] [746-750a]. Sclareol is the main component in the concrete, obtained by solvent extraction of S. sclarea L. leaves [750b]. 

Alteration of essential-oil components during distillation can be recognized by comparing the oils obtained by steam distillation and by SFE. The hydrolysis of esters (like linalyl acetate) to the corresponding alcohols was observed in clary sage oils. The hydrolysis of thymol bound in glycosides resulted in different thymol concentrations in distilled thyme oils, which was proved by appropriate treatments (acidic and enzymatic) of the previously CO2-extracted plant material. 

Flowery Anisyl alcohol Benzyl acetate, phenylaceiate Cinnamic acid Cinnamyl acetate Citronellyl formate Crcsyl acetate Decanal Dimethyl benzyl carbinol Dimethyl benzyl carbinyl acetate Ethyl anthranilate Geranyl acetate Hydroxycitronellal dimethyl acetate Linalool Linalyl acetate Methyl benzoate Pcnethyl acetate 2-Phcnylpropionaldehyde 3-Phenylpropionaldehvde. 

Of this residue, dissolved in a little neutral alcohol, the acid and ester numbers are determined, these being due to resinous, fatty and waxy substances naturally present in the bergamot oil. The ester number is converted into the corresponding percentage (n) of linalyl acetate (see paragraph 2) and the quantity of this ester contained in the percentage ( -) of residue left by the oil then calculated from the formula, (n x r)/ioo. This amount of linalyl acetate is subtracted from that found in the oil, as in paragraph . 

Detection of Terpinyl Acetate (SchimmeVs method).—The saponification of the linalyl acetate of bergamot oil is complete after 15-30 minutes boiling with N/2-alcoholic potash, but with terpinyl acetate at least an hour is necessary for complete saponification. The latter ester may thus be detected by carrying out two distinct saponifications, one for 30 minutes... 

A bergamot oil which does not correspond with the more important of the above specific characters for the genuine oil is to be regarded as adulterated. This is the case, for instance, with an oil having D below o-88o or above 0-887 or ci below + 70 or above + 250, or containing less than 33% or more than 45% °f esters (as linalyl acetate), or not dissolving completely in half its volume of cfo% alcohol. 

Iodolactonization of y, o-unsaturated alcohols results in preferential formation of tram-2, 5-disubstituted tetrahydrofuranes. However, the corresponding benzyl ethers cyclize preferentially to the cis-isomers. The alkyl group must be bulky enough to exert a steric effect, but not to prevent cyclization. Substituted benzyl ethers are particularly useful. Examples of this steric control are illustrated for the preparation of tram- and c/s-linalyl oxide (equations I and II).10... 

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