Epoxidation Of Α-pinene Research Articles

Lipase-mediated epoxidation of α-pinene

This work describes the lipase-mediated synthesis of α-pinene oxide at ambient temperature. The immobilized lipase from Candida antarctica (Novozyme 435) is used to generate peroxyoctanoic acid directly from octanoic acid and hydrogen peroxide. The peroxy acid formed is then applied for in situ oxidation of α-pinene. High conversion of α-pinene to α-pinene oxide (approximately 70%) was achieved when using a two-phase system of toluene and water. Various parameters affecting the conversion of α-pinene to α-pinene oxide were studied.

Catalytic epoxidation of α-pinene over bifunctional mesoporous molecular sieves

Bifunctional titanium-mesoporous molecular sieves containing different trivalent ions, e.g. B3+, Al3+ or Fe3+, were synthesized and characterized. These catalysts, which contain both acid and oxidizing catalytic sites, are very active in epoxidation of bulky olefins and highly selective in diol formation. A reasonably good stability and re-usability are also observed.

Epoxidation of α-Pinene with Molecular Oxygen Catalyzed by Poly(vinylbenzyl)acetylacetonate Complexes of Some Metal Ions

Poly(vinylbenzyl)acetylacetonate complex of cobalt is a very effective catalyst for the epoxidation of α-pinene under an atmospheric pressure of molecular oxygen at 25°C. With isobutyraldehyde as a reductant, the yield of the epoxidation of α-pinene amounts to 94.3% within 6 hr. The catalyst can be recycled at least eight times without apparent loss of activity.

Epoxidation of α-Pinene with Molecular Oxygen Catalyzed by Poly(vinylbenzyl)acetylacetonate Complexes of Some Metal Ions

Epoxidation of α-Pinene with Molecular Oxygen Catalyzed by Poly(vinylbenzyl)acetylacetonate Complexes of Some Metal Ions

Magnesium oxide-supported polytitazane cobalt(III) complex for catalytic epoxidation of ?-pinene with molecular oxygen

Magnesium oxide-supported polytitazane cobalt complex has been prepared and found to be a very effective catalyst for the epoxidation of α-pinene in the presence of an aldehyde as a reductant. XPS data show that the high valent cobalt(III) was stabilized by the mutidentate nitrogen ligand of polytitazane. The α-pinene oxide can be obtained in 96.0% yield with 96.6% selectivity at 25°C under an atmospheric pressure of molecular oxygen. Isobutyraldehyde is an effective reductant and only 1.2 equivalent of isobutyraldehyde to α-pinene is needed to ensure high yield of α-pinene oxide. The catalyst is also very stable and can be reused at least eight times without loss of its activity.

Ring opening of α-pinene epoxide

The acid-catalysed opening of the epoxide ring of α-pinene epoxide (2α,3α-epoxypinene) has been shown to proceed without participation of cyclobutane ring expansion in the rate-determining step. The reaction cannot proceed by initial C–O bond fission, as intermediates generated by either fission are on other reaction pathways. It is suggested that the reaction proceeds by fission of the C–C bond to give a heterocyclic intermediate, which can ring open, and finally expand the cyclobutane ring in the product-determining step. Reactions which could proceed by a similar mechanism are discussed. The corresponding reaction of β-pinene epoxide (2β,10-epoxypinene) in which the epoxide ring is not part of a strained bicyclic system, proceeds via this route to the extent of only 0.5%. The main reaction involves conventional C–O bond fission.

ChemInform Abstract: CATALYTIC REARRANGEMENT OF AN α‐PINENE EPOXIDE IN THE PRESENCE OF ALUMINUM ALKOXIDE

Chemischer InformationsdienstVolume 14, Issue 4 Natural Products ChemInform Abstract: CATALYTIC REARRANGEMENT OF AN α-PINENE EPOXIDE IN THE PRESENCE OF ALUMINUM ALKOXIDE F. SCHEIDL, F. SCHEIDLSearch for more papers by this author F. SCHEIDL, F. SCHEIDLSearch for more papers by this author First published: January 25, 1983 https://doi.org/10.1002/chin.198304346Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume14, Issue4January 25, 1983 RelatedInformation

Conversion of α-pinene to α-pinene oxide by rat liver and the bark beetle Dendroctonus terebrans microsomal fractions

The metabolism of α-pinene, a major monoterpene in Pinus spp. in the United States, has been examined utilizing microsomal fractions from larval and adult Dendroctonus terebrans and rat liver. Under hydroxylating conditions, both insect and rat liver microsomes convert α-pinene into α-pinene oxide and several other undentified products. α-Pinene oxide was identified by mass spectrometry. α-Pinene is an inducer of cytochrome P-450 in rat liver microsomes and its effect on the pattern of α-pinene metabolism is very similar to β-naphthoflavone. No increase in cytochrome P-450 was observed when insects were treated with α-pinene; however, the quantity of α-pinene metabolic products was increased by α-pinene pretreatment. The role of cytochrome P-450 linked reactions in the production of insect pheromones via the α-pinene epoxide intermediate is discussed.