104975-22-6Relevant academic research and scientific papers
OXYGENATED DERIVATIVES OF MENTHATRIENE IN PARSLEY LEAVES
Nitz, Siegfried,Kollmannsberger, Hubert,Spraul, Martin H.,Drawert, Friedrich
, p. 3051 - 3054 (1989)
The analysis of aroma volatiles of parsley revealed the presence of two novel oxygenated p-mentha-1,3,8-tiene derivatives, the amounts of which increase during processing of plant material and deteriorate the typical fresh aroma.The two derivatives, which could be synthesized by means of a dye sensitized photooxygenation reaction, were identified as 1-methyl-4(methylethenyl)-2,3-dioxabicyclooct-5-ene and 4-methyl-7-(methylethenyl)-3,8-dioxatricyclo2-4>octane.Key Word Index - Petroselinum crispum; Umbelliferae; parsley; aroma volatiles; p-mentha-1,3,8-triene; dioxetane; 1-methyl-4-(methylethenyl)-2,3-dioxabicyclooct-5-ene; diepoxide; 4-methyl-7-(methylethenyl)-3,8-dioxatricyclo2-4>octane.
Visible-light photosensitized oxidation of α-terpinene using novel silica-supported sensitizers: Photooxygenation vs. photodehydrogenation
Ronzani, Filippo,Costarramone, Nathalie,Blanc, Sylvie,Benabbou, Abdelhamid Khalil,Bechec, Mickael Le,Pigot, Thierry,Oelgemoeller, Michael,Lacombe, Sylvie
, p. 164 - 174 (2013)
Three silica-immobilized organic photocatalysts, based on rose bengal (RB), antraquinone-2-carboxylic acid (ANT-COOH) and a new cyanoanthracene derivative (DBTP-COOH), were prepared and characterized. Their efficiency for the photooxidation of α-terpinene was compared to that of their soluble counterparts. In solution, the three sensitizers showed high quantum yield of singlet oxygen production. Significant autooxidation to p-cymene occurred in the absence of catalyst while the mechanism of the sensitized reaction strongly depended on sensitizer structure. With DBTP and RB materials, ascaridole was rapidly produced by singlet oxygen addition. In contrast, ANT-based sensitizers favored photodehydrogenation to p-cymene through an electron-transfer step inducing a radical chain reaction, followed by further p-cymene oxidation upon prolonged irradiation. The highest efficiency and selectivity were obtained for photooxygenation with DBTP-based materials, and for photodehydrogenation with ANT-based materials, these properties make them attractive for future applications as immobilized photocatalyst in solar synthesis, waste treatment, and microflow reactors.
Easy Epoxidation of Monoterpenes from Common Starting Materials
Benitez, Ricardo B.,Bermudez, John H.,Franco, Jaime M.,Rojas, Giovanni
, p. 1086 - 1092 (2020/10/14)
Epoxidation of monoterpenes, α-pinene, β-pinene, limonene, α-terpinene, and (R)-carvone was carried out by the in situ production of a peroxyacid rather than direct addition of such an expensive and difficult to handle chemical. Previous reports showed use of metal catalysts with high yields, while methodologies without catalysts at high temperature showed yields lower than 30%. The authors report a methodology that produces peroxyacetic acid in situ yielding up to 75% pure epoxide at room temperature avoiding the use of catalysts. The products were analyzed by gas chromatography mass spectrometry (GC-MS), and structures were characterized by 1H and 13C nuclear magnetic resonance (NMR).
Comparative analysis of three Australian finger lime (Citrus australasica) cultivars: Identification of unique citrus chemotypes and new volatile molecules
Delort, Estelle,Jaquier, Alain,Decorzant, Erik,Chapuis, Christian,Casilli, Alessandro,Frérot, Eric
, p. 111 - 124 (2015/02/19)
The volatile constituents of the peel of three cultivars of Australian finger lime (Citrus australasica) were investigated: Alstonville, Judy's Everbearing and Durham's Emerald. Both qualitative and quantitative GC-MS analyses were performed on their peel solvent extract. The results showed that the unique phenotypes of finger lime are also correlated to unique molecular compositions. Each cultivar revealed a different chemotype: limonene/sabinene for cv. Alstonville, limonene/citronellal/isomenthone for cv. Judy's Everbearing, and limonene/citronellal/ citronellol for cv. Durham's Emerald. To the best of our knowledge, these chemotypes have never been reported in any other citrus species. Furthermore, the amounts of some volatile constituents (γ-terpinene, α-pinene, β-pinene, citral), which are generally the major constituents besides limonene in lime species, were surprisingly low in the three cultivars. Comparative GC-MS analysis also showed that some volatile molecules tended to be specific to one cultivar and could therefore be considered as markers. Moreover six molecules were reported for the first time in a citrus extract and confirmed by synthesis. Heart-cutting enantioselective two-dimensional GC-MS was performed to determine the enantiomeric distribution of the major chiral constituents. The combined data on three finger lime cultivars gives evidence of their divergence from other citrus species.
Ruthenium(II)-Catalyzed Reactions of 1,4-Epiperoxides
Suzuki, Masaaki,Ohtake, Hiroaki,Kameya, Yoshimi,Hamanaka, Nobuyuki,Noyori, Ryoji
, p. 5292 - 5302 (2007/10/02)
The behavior of 1,4-epiperoxides in the presence of transition-metal complexes is highly dependent on the structures of the substrates and the nature of the metal catalysts.Reaction of saturated epiperoxides such as 1,3-epiperoxycyclopentane, 1,4-epiperoxycyclohexane, or dihydroascaridole catalyzed by RuCl2(PPh3)3 in dichloromethane gives a mixture of products arising from fragmentation, rearrangement, reduction, disproportionation, etc.Prostaglandin H2 methyl ester undergoes clean and stereospecific fragmentation to afford methyl(5Z,8E,10E,12S)-12-hydroxy-5,8,10-heptadecatrienoate and malonaldehyde.Bicyclic 2,3-didehydro 1,4-epiperoxides give the syn-1,2:3,4-diepoxides by the same catalyst.The monocyclic analogues are transformed to a mixture of diepoxides and furan products.The stereochemical outcome of the epoxide formation reflects unique differences in the ground-state geometry of the starting epiperoxide substrates.FeCl2(PPh3)2 serves as a useful catalyst for the skeletal change of sterically hindered bicyclic 2,3-didehydro 1,4-epiperoxides to the syn-diepoxides.In addition, the Fe complex best effects the conversion of 1,4-unsubstituted 2,3-didehydro epiperoxides to furans.The Ru-catalyzed reactions are interpreted in terms of the intermediacy of inner-sphere radicals formed by atom transfer of the Ru(II) species to peroxy substrates, in contrast to the Fe-catalyzed reactions proceeding via free, outer-sphere radicals generated by an electron-transfer mechanism.
Competitive Reactions of Diene Cation Radicals Formed on Irradiated Metal Oxide Surfaces
Fox, Marye Anne,Sackett, Debra D.,Younathan, Janet N.
, p. 1643 - 1660 (2007/10/02)
The heterogeneous photochemical oxygenation of conjugated dienes induced by long wavelength UV irradiation of TiO2 powders suspended in oxygenated CH3CN was studied.In nearly all cases, products resulting from the oxidative cleavage of the double bonds were observed, in parallel to that previously reported for monoolefins.A mechanism is proposed which involves the intermediacy of a diene cation radical generated by transfer of an electron from the adsorbed diene to a photogenerated hole localized at the surface of the excited TiO2 particle.Non-oxidative cleavage products are also observed, and the effect of the semiconductor surface in controlling reactivity of the photogenerated cation radical is discussed.The first examples of aromatization and Diels-Alder dimerization mediated by irradiated semiconductor suspensions are presented.
