Isopulegol oxidation

On oxidation isopulegol yields isopulegone, which can be characterised by its oxime, which melts at 121° for the active, and about 140" for the inactive variety or its semi-carbazone, which melts at 172° to 173° for the active, and 182° to 183" for the inactive variety. 

Isopulegol, 24 517-519, 526 Isoquinoline. See also Isoquinolines reduction of, 27 201 uses for, 27 206-208 Isoquinoline derivatives. See also Isoquinolines drugs, 27 207—208t synthesis of, 27 201-206 uses for, 27 206-208 Isoquinoline TV-oxide, 27 200-201 Isoquinolines, 27 182, 200-208 alkyl, 27 205... 

Isoproterenol, chemiluminescence, 647 (—)-Isopulegol, artemisinin synthesis, 277, 278 Isothermal microcalorimetry, oxidation stability evaluation, 672 Isotopomers... 

As shown in Scheme 20, manipulation of (-)-isopulegol as described previously108 provided smooth access to the Robinson precursor hydroboration of (-)-isopulegol with oxidative workup followed by selective protection provided alcohol 246, followed by Swern oxidation to give 247.49 Generation of the kinetic enolate of 247 with LDA at low temperature followed by Michael addition to 3-trimethylsilyl-3-buten-2-one gave, after mild in situ hydrolysis of the a-silyl... 

Selenium dioxide oxidation of isopulegol acetate (133 3R) and neoisopulegol acetate (133 35) is reported 223 allylic oxidation is consistent with the Sharpless mechanism but a different mechanism is proposed. 

In two seminal papers, Sharpless presented evidence for a two-step mechanism for the SeO, oxidation. On reaction of ( —)-isopulegol (1) with Se02 in ter/-butanol at 80°C, the pure seleninolactone 2 was obtained in 39% yield7. This finding was interpreted as evidence in support of an initial ene reaction of a Se - O moiety to yield an allylseleninic acid, which is trapped intramolecularly by the OH group. 

Brocksom et al. have shown that isopulegols (e.g., 169) can be oxidized to the hydroxy ether 645 by thallium triacetate, without loss of stereochemistry. ... 

The ortho ester 681 of menthane-3,8,9-triol has been isolated from Mentha piperita and synthesized from (- )-isopulegol (169). Osmium tetroxide oxidation... 

Despite the fact that the presence of heteroatoms on the carbon surface can induce some types of active phase-support interaction, as discussed above, it is clear that this takes place to a lesser extent that in other common catalyst supports, such as oxides (silica, alumina, titania, ceria, etc.). One clear example is provided in work carried out by Milone et al. [28], in which they investigated the influence of the surface area and the nature of the support on product distribution in the hydrogenation of citronellal (3,7-dimethyl-6-octen-l-al) on Ru supported on silica and carbon. It was found that the main products obtained on the Ru/Si02 catalyst were the unsaturated cyclic alcohols (isopulegols), which were produced via the isomerization of cinonellal on the Si02 surface. However, the main reaction products on Ru/C were the open-chain hydrogenated products (i.e., citronellol,... 

Isopropyl propionate Isopropyl tiglate Isopulegol Isopulegone Isopulegyl acetate Isoquinoline Isosafrole Isovaleraldehyde Isovaleric acid cis-Jasmone Laurie aldehyde Lauryl acetate Lauryl alcohol Lepidine Levulinic acid d-Limonene dl-Limonene Linalool Linalool oxide Linalyl acetate... 

Cascarilla oil perfume, cranberry Cascarilla oil perfume, detergents Diphenyl oxide perfume, geranium Isopulegol perfume, herbal Cascarilla oil Piperitenone perfume, nutmeg Cascarilla oil perfume, personal care dl-Limonene perfume, pomades Lard... 

Suggest a mechanism for the following thallium(III)-mediated oxidative cyclization of the homoallylic alcohol (-)-isopulegol, which was a crucial step in a synthesis of mintlactone (Ferraz, H. M. C et al. J. Org. Chem. 2000,65,2606-2607) ... 

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