Trans-linalyl oxide

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-... 

Iodoetherification has been used in the synthesis of cis and trans linalyl oxides. Mechanistically, the rate of departure of the hydroxyl protecting group in the starting 7,8 unsaturated ether was found to be critical to the stereochemistry of the product.218 The alkyl group R (Scheme 47) must be sufficiently bulky as to... 

Fig. 17.14 Simultaneous stereoanalysis of Lavandula oil constituents, using enantio-MDGC (standard mixture), a Preseparation of racemic compounds unresolved enantiomeric pairs of octan-3-ol (6, 7), frcms-linalool oxide (1, 2), oct-l-en-3-ol (9, 10), ds-linalool oxide (3, 4), camphor (5, 8), linalool (17, 18), linalyl acetate (11, 12), terpinen-4-ol (15, 16) and lavandulol (13, 14). b Chiral resolution of enantiomeric pairs, transferred from the precolumn trans-linalool oxide 1 (2S,5S), 2 (2R,5R) ds-linalool oxide 3 (2R,5S), 4 (2S,5R) camphor 5 (IS), 8 (IR) octan-3-ol 6 R, 7S oct-1-en-3-ol PS, 10 R linalyl acetate 11 R, 12 S lavandulol 13 R, 14 S terpinen-4-ol 15 R, 16 S linalool 17 R, 18 S. [75]...

This cyclization can be used to prepare cii-linalyl oxide (2) in 70% overall yield from the benzyl ether 1. Under the same conditions, the correspionding free alcohol is converted into trans-2 in comptirable yield. ... 

Investigations on authentic essential oils of Lavandula species are summarized in Table 6.20, detecting the chiral monoterpenoids with high enantiomeric purities as characteristic constituents of genuine lavender oils Besides R-linalyl acetate (11) and R-linalool (17), the chiral main compounds of genuine lavender oils 2R-trans-(2), 2R-cis-(3)-linalool oxide (fur.), (R)-lavandulol (13), as well as S-terpinen-4-ol (16) are detected [111]. 

Linalool, linalyl acetate, fenchone, camphor Trans-calamenene, 5-cadinene, P-caryophyllene, leptospermone Piperitenone oxide, limonene, tltymol, carvacrol, p-cymene, P-caryophyllene, and y-terpinene... 

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