Nerol oxidation

Nerol oxide Nerve agents Nerve degeneration Nerve fibers Nerve gas... 

Of all these, probably P-phenethyl alcohol (2) comes closest to the odor of fresh rose petals however, mixing all these components does not reproduce the total fine character of the natural oil. It has been determined that a number of trace constituents representing less than 1% of the volatiles are critical to the development of the complete rose fragrance (10). These include cis- and trans-i.ose oxide (1), nerol oxide (12), rose furan (13), /)i7n7-menth-l-en-9-al (14), P-ionone (15), P-damascone (16), and P-damascenone (3). 

Nerol, oxidation, 788-9, 790 Neuroprostanes, H2-isoprostane bicycUc endoperoxides, 612 Neutron diffraction analysis, hydrogen peroxide, 96... 

Cyclic ethers used as fragrances include a number of terpenoid compounds. Some of them, such as 1,4-cineole [470-67-7] and 1,8-cineole, occur in essential oils in significant quantities. Others are only minor components examples are rose oxide, nerol oxide [1786-08-9], and rose furan [15186-51-3], which contribute to the specific fragrance of rose oil. Caryophyllene oxide [1139-30-6], which has a woody,... 

Nerol oxide Sambucus nigra (elderberry) (Caprifoliaceae) OD-R... 

N.m.r. assignments for campholenic aldehyde, car-3-ene, /3-cyclocitral, three lavandulyl derivatives, and nerol oxide, as well as for 24 acyclic, 39 p-methane, six bicyclo[3,l,0]hexane, twelve bicyclo[2,2,l]heptane, and eight bicyclo[3,l,l]heptane monoterpenoids are recorded. ... 

Figure 5.1a (Continued) octadiene-3,6-diol) (11) hydroxycitronellol (3,7-di methyloctane-l,7-diol) (12) 8-hydroxydihydrolinalool (2,6-dimethyl-7-octene-l,6-diol) (13) 7-hydroxygeraniol (E-3,6-dimethyl-2-octene-l,7-diol) (14) 7-hydro-xynerol (Z-3,6-dimethyl-2-octene-l, 7-diol) (15) cis and trans 8-hydroxy linalool (E- and Z-2,6-dimethyl-2,7-octadiene-l,6-diol) (16) p-menthenediol I (p-menth-l-ene-7,8-diol) (17) E-geranic acid (3,7-dimethyl-2,6-octadienoic acid) (18) E-2,6-dimethyl-6-hydroxyocta-2,7-dienoic acid (19) E- and Z-sobrerol or p-menthenediol II (p-menth-l-ene-6,8-diol) (20) cis and trans rose oxide (21) nerol oxide (22) 2-exo-hydroxy-1,8-cineol (23) 1,8-cineol (24) wine lactone (25) cis and trans 1,8-terpin (26) triol (2,6-dimethyloctane-2,3,6-triol) (27) hotrienol [(5E)-3,5-dimethylocta-l,5,7-trien-3-ol] (28) myrcenol (2-methyl-6-methylene-7-octen-2-ol)...

CIC Green, fruity, fatty esters like (Z)-3-hexenyl butyrate, (Z)-3-hexenyl hexanoate, 2-ethyl hexenoate, 2-ethyl-octenoate form the basic fruity body. Nerol oxide and edulan add an ethereal, fresh, green, sharp, floral topnote. The floral note (mainly in the purple variety) is represented by linalool with a complex of ionone derivatives, mainly beta-ionone, dihydro-beta-ionone, theaspirone, damascenone. The key components for the green, exotic, sulfury topnote of the yellow variety are 2-methyl-4-propyl-l,3-oxathiane and 3-methylthio-l-hexanol. 

Damage to the flavor of "Asti Spumante" wines stored at 20 C when compared with samples held at 10 C was related to losses of linalool and glycosidic precursors of linalool, geraniol and nerol (87). Also the concentrations of a-terpineol, hotrienol, nerol oxide and the furan linalool oxides increased in wines held at ambient temperature. Di Stefano and Castino (87) concluded that low temperature storage retarded these reactions and wines so held retained the characteristic muscat flavor for years. 

Ohloff et al. have synthesized the optically active nerol oxides (914A and 914B) from (- )-(R)-linalool [(R)-28] following the route in Scheme 70. In the last step, dehydration with phosphorous oxychloride in pyridine, some of the exocyclic isomers 915 were produced. Reduction of the nerol oxides (914) and the isomers 915 to rose oxide (909) were mentioned in Vol. 4 (p. 565, Refs. 123 and 773), and some specific conditions to furnish a maximum of the cis-isomer of 909 from 915 have been given, the cw-isomer being the more powerful smelling. ... 

The hydroxyocimenone 916 (Vol. 4, p. 474, Ref. 163) has been converted to nerol oxides (914) by the action of sulfuric acid on the diol obtained from 916 with lithium aluminum hydride. ... 

The same procedure was performed with nerol oxide to give the crystalline lactone in 22% yield257. With 2-(l-propenyl)thiane the thiolactone only was obtained in 8% yield. The naturally occurring 10-membered lactones ( )-phoracantholides 1 and J were prepared using this methodology257. 

The occurrence and syntheses of rose oxides, dihydrorose oxides, rosefuran, and nerol oxides, together with related compounds, have been reviewed. The structure of a cyclic monoterpenoid ether from Artemisia tridentata, which is related to the santolinyl monoterpenoids, has been confirmed (c/. Vol, 7, p. 20) as (227) and renamed artemiseole (c/. Vol. 8, p. 58 for an incorrect structural deduction).Interestingly, another new component of A. tridentata, the (3S)-diastereoisomer of (74), with formic acid yields (227) in contrast to (74) which yields the acyclic aldehyde (228). ° It is possible that some of the 31% of unidentified components in the essential oil of A. annua may correspond to these new compounds.The quinone (229) has been isolated from Lithospermum erythrofhizon, and further details on the presence of aeginetolide in Aeginetia indica have been published. 

Crombie s group has also discussed the biogenesis of these monoterpenoids, giving examples of the various possibilities of the scission of the chrysanthemyl skeleton to the other skeletons, including the synthesis of the dehydrolavandulol (67) from a n s-chrysanthemic diol (68). They report some feeding experiments with C-labelled chrysanthemate, but incorporation into artemisia ketone was very low. The synthesis of a cyclopropyl terpenoid once discussed by Robinson as a possible biogenetic intermediate to artemisia ketone has been accomplished from nerol oxide it is discussed in the section on pyranoid monoterpenoids (below). 

When nerol oxide (419) is metallated with butyl-lithium, a sigmatropic rearrangement of the anion to (420) occurs. The two isomers of (420) can be trapped in acetic anhydride as the enol acetates (421), hydrolysis of the latter yielding the aldehydes (422). " Additional interest is given to this reaction because the... 

In view of their high perception thresholds (1-5 mg/1), linalol and nerol oxides have very little olfactory impact on wines. Rose oxide is a more odoriferous compound. According to Guth (1997), it is partly responsible for the floral aroma of Gewiirztraminer wines. 

Oil of thyme contains p-myrcen-8-ol derived from p-myrcene, and (i )-(-)-ipsdienol as well as its non-chiral regioisomer is not only the aggregation pheromone of the bark beetle Ips confusus, but also the fragrance of the blossoms of many orchids. Terpenoid pyran derivatives include diastereomeric rose oxides [(2/ ,4/ )-trans- and (2S,4R)-cis-] as well as racemic nerol oxide, which essentially contribute to the pleasantly flowery green smell of the Bulgarian oil of rose... 

The ene reaction of isovaleraldehyde with isoprene provides a 16% yield of ipsenol (7), a pheromone of the bark beetle ips confusus (see Figure 3). lo The major product formed in 60% yield is the Diels-Alder adduct 8 which is related to nerol oxide and rose oxide. Use of Me 2A1Q allows the isolation of acid-sensitive ipsenol, since protic acids are not present in the reaction mixture. The reaction of aldehydes with limonene occurs exclusively at the less substituted double bond as reported by Blomquist for the reaction with formaldehyde. 3a Isovaleraldehyde and limonene give a 70% yield of 9, an intermediate in Crawford s dihydro-ar-turmerone synthesis, n... 

The dye-sensitized photooxygenation reaction has to be considered as a biomimetic process 451) involved in the formation of deoxylinalool oxide (132) 459), rose oxide (134) 456) and nerol oxide (135) 459) from linalool (6), citronellol (9) and nerol (8), respectively. 

In addition a broad pattern of aroma-active monoterpenes (e. g., nerol oxide, hotrienol) is formed by cyclization and dehydration reactions of di- and polyhydroxylated monoter-penes (examples, cf. S.3.2.4), e.g., the cis-rose oxides can be formed by the cyclization of 3,7-dimethylocta-6-en-l,5-diol. 

Numerous other ethers containing pyran or furan rings are formed by the dehydration of aliphatic diols (e.g. linalool oxides, rose oxide or nerol oxide) and are components of many essential oils. For example, the furanoid 2R,5R)- E)- and (2J ,5S)-... 

Epoxycaryophyllene (-l-)-DIII ether (-l-)-Menthofuran (H-)-1,8-Clneol (-)-Nerol oxide (-)-(Z)-Rose oxide... 

Z)- and pyranoid 3R,6R)- Z)- and (3S,6S)-(Z)-linalool oxides (8-32) are odorants of jasmine tea, aromatic wines, elderberry bush flowers and linden honey. In grapes, (-)-(Z)-rose oxide from (-)-citroneUol is analogously produced. Rose oxide is also a component of rose and geranium essential oils (8-32). Nerol oxide in rose oil is a racemate. 

SSjOil-cA-pyranoid linalool oxide (3/J,6/f)-cw-pyranoid linalool oxide (-)-nerol oxide... 

Important fragrance components of rose oil include (4R)-cis-rose oxide, 4R)-trans-Tose oxide, ( )-nerol oxide, 3-(4-methyl-3-pentenyl)-2-buten-4-olide, 3-methyl-4-(3-methyl-2-butenyl)-2-buten-4-olide, cis- and tran5-2-(3-methyl-2-butenyl)-3-methyl tetra-hydrofuran, P-damascenone, 3-hydroxy-P-damascenone, and P-damascone. ... 

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