- Biomass to chemicals: Rearrangement of β-pinene epoxide into myrtanal with well-defined single-site substituted molecular sieves as reusable solid Lewis-acid catalysts
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The epoxide rearrangement of β-pinene oxide into myrtanal was studied in the presence of solid Lewisacid catalysts. Different metals such as Zr, Sn, Ti, Nb, Ta, Al, and Ga have been incorporated within network positions of zeolite Beta by isomorphous substitution. The materials have been characterized by powdered X-ray diffraction (XRD), IR spectroscopy and by in situ IR spectroscopy on adsorbed molecules (cyclohexanone and pyridine). Among the studied catalysts Zr-Beta gave the best selectivity (up to 94%) in acetonitrile as solvent at practically complete conversion. In this epoxide rearrangement the solvent has to be selected to balance the competitive adsorption of the product. Product desorption is enhanced with acetonitrile which results in a selectivity increase with only a small penalty on the rate of reaction. Zr-Beta has been reused in the batch mode and in a fixed-bed reactor for several times and analysis of the reused catalyst indicated that Zr-Beta is a robust catalyst for the epoxide rearrangement. Leaching of the metal or crystal degradation has not been detected.
- De La Torre, Olalla,Renz, Michael,Corma, Avelino
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- Homogeneous Lewis and Br?nsted acids as catalysts for β-pinene oxide rearrangement to prepare myrtenol and myrtanal
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Myrtenol and myrtanal find their utilization as fine chemicals or intermediates for the synthesis of food additive myrtanol. β-Pinene oxide rearrangement was studied using homogeneous Lewis and Br?nsted acids as catalysts for the production of these compounds. The composition of reaction products depended on the type of active sites. Lewis active sites favoured the formation of myrtanal while in presence of Br?nsted active sites undesirable perillyl aldehyde and perillyl alcohol were formed to a high extent. Optimal reaction conditions for myrtenol and myrtanal preparation were found. With 5 mol.% of anhydrous SnCl2 as Lewis acid catalysts and 1,4-dioxane as the solvent β-pinene oxide achieved total conversion with 95% selectivity to desired products.
- Cerveny, Libor,Fidlerova, Barbora,Paterova, Iva,Vavra, Michal,Vyskocilova, Eliska
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- One-Pot Myrtenol Amination over Au, Au–Pd and Pd Nanoparticles Supported on Alumina
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Abstract: One-pot bio-based myrtenol amination was studied in the presence of alumina supported Au, Au–Pd and Pd nanoparticles subjected to the thermal treatment under oxidizing or reducing atmosphere. Myrtenol amination with aniline was carried out under nitrogen atmosphere (9?bar) at 453?K using toluene as a solvent. The effect of the active metal along with the influence of redox pre-treatment on the catalytic behavior in the hydrogen borrowing reaction was explored. The catalyst characterization was done by transmission electron microscopy, X-ray photoelectron spectroscopy, inductively coupled plasma optical emission spectroscopy, nitrogen adsorption. The active metal and the catalysts redox pretreatment affected more noticeably selectivity to the reaction products rather than myrtenol conversion. Monometallic Au/Al2O3 catalyst promoted predominantly formation of the target secondary amine and the corresponding imine without a significant impact of the side reaction of C=C bond hydrogenation in myrtenol, whereas monometallic Pd catalyst activated C=C bond resulting in its hydrogenation. At the same time in the presence of Au–Pd simultaneous hydrogenation of both C=C and C=N bond occurred. Au–Pd catalysts activated in oxygen and hydrogen showed different catalytic activity determined by the composition of surface active sites. Monometallic gold catalyst was more effective in the hydrogen transfer in the case of substrates with competitive unsaturated functional groups. Graphic Abstract: [Figure not available: see fulltext.].
- Demidova, Yu. S.,Simakova,Estrada,Beloshapkin,Suslov,Volcho,Salakhutdinov,Simakov,Murzin, D. Yu.
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- Preparation of α-terpineol and perillyl alcohol using zeolites beta
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The preparation of α-terpineol by direct hydration of limonene catalyzed by zeolites beta was studied. The same catalyst was used to prepare perillyl alcohol by isomerization of β-pinene oxide in the presence of water. The aim was to optimize the reaction conditions to achieve high conversions of starting material and high selectivity to the desired products. In the case of limonene, it was found that the highest selectivity to α-terpineol was 88% with conversion of 36% under the conditions: 50?wt% of catalyst beta 25, 10% aqueous acetic acid (10?mL) (volume ratio limonene:H2O = 1:4.5), temperature 50?°C, after 24?h. In the case of β-pinene oxide, it was found that the highest selectivity to perillyl alcohol, which was 36% at total conversion, was obtained in the reaction under the following conditions: dimethyl?sulfoxide as solvent (volume ratio β-pinene oxide:DMSO = 1:5), catalyst beta 25 without calcination (15?wt%), demineralized water (molar ratio β-pinene oxide:H2O = 1:8), temperature 70?°C, 3?h. The present study shows that the studied reactions are suitable for the selective preparation of chosen compounds.
- ?erveny, Libor,Vysko?ilová, Eli?ka,Zítová, Kate?ina
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p. 4297 - 4310
(2021/07/26)
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- Selective Allylic Oxidation of Terpenic Olefins Using Co-Ag Supported on SiO2 as a Novel, Efficient, and Recyclable Catalyst
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Co-Ag supported on the SiO2 catalyst was synthesized by the sol-gel method and characterized using XRD, FT-IR, TG-DTG, BET, CV, and SEM/EDX analysis. The catalytic performance of the resulting catalyst was examined by the oxidation of mono and sesquiterpenic olefins using hydrogen peroxide and tert-butyl peroxide as oxidant agents. Various parameters such as catalyst amount, temperature, and solvents have been studied. The Co-Ag supported on the SiO2 catalyst showed a high activity, selectivity, and recyclability for the selected oxidation reaction.
- Aberkouks, Abderrazak,Mekkaoui, Ayoub Abdelkader,Ait Ali, Mustapha,El Firdoussi, Larbi,El Houssame, Soufiane
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- Photocaged Hydrocarbons, Aldehydes, Ketones, Enones, and Carboxylic Acids and Esters that Release by the Norrish II Cleavage Protocol and Beyond: Controlled Photoinduced Fragrance Release
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Five families of caged fragrance compounds that allow the storage and release of the following small volatile organic molecules are described: terpene hydrocarbons, aldehydes, ketones, Michael-type α,β-unsaturated enones, and carboxylic acids and esters. These caged molecules are released by photoexcitation via carbonyl-directed hydrogen-transfer processes and subsequent C-C bond cleavage (Norrish Type II) or by didenitrogenation of diazirines.
- Griesbeck, Axel G.,Porschen, Bj?rn,Kropf, Christian,Landes, Agnieszka,Hinze, Olga,Huchel, Ursula,Gerke, Thomas
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p. 539 - 553
(2017/01/25)
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- A preparation method of Myrtle myristic aldehyde
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The invention discloses a preparation method of myrtanal. The method sequentially comprises the following steps: 1, carrying out a hydroboration-oxidation reaction on beta-pinene to generate myrtanol; and 2, carrying out a selective oxidation reaction on myrtanol and active dimethyl sulphoxide to generate myrtanal. Myrtanol is synthesized in a high efficiency manner through hydroboration-oxidation of beta-pinene as a raw material, and the yield is greater than 90%; myrtanal is prepared through selective oxidation of the active dimethyl sulphoxide at room temperature, and the yield is greater than 80%, so the total yield of conversion from the initial raw material beta-pinene to myrtanal is greater than 72%. Compared with present methods, the method disclosed in the invention has the advantages of cheap and easily available reaction raw materials, mild reaction conditions, high purity and high yield of the above obtained product, and great reduction of the preparation cost of myrtanal.
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Paragraph 0050; 0051; 0052; 0053; 0054; 0055
(2017/07/04)
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- Continuous flow photooxygenation of monoterpenes
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Photooxygenation of monoterpenes was conducted in two continuous flow reactors. The first, suitable for lab-scale research, had a maximum yield of 99.9%, and the second, focused on industrial applications, showed a daily output that was 270.0-fold higher than that in batch systems. The use of sunlight instead of an LED lamp gave 68.28% conversion.
- Park, Chan Yi,Kim, Young Joon,Lim, Hyo Jin,Park, Jeong Hyeon,Kim, Mi Jin,Seo, Seung Woo,Park, Chan Pil
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p. 4233 - 4237
(2015/02/19)
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- PRODUCTION OF MYRTANAL FROM BETA-PINENE EPOXIDE
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The present invention relates to a procedure for the production of myrtanal from β-pinene epoxide, comprising as a minimum putting said epoxide in contact with a crystalline microporous catalyst having pores of diameter of at least 0.52 nm and having an empirical formula in dehydrated calcined form of Hw(MwTixSnyZrzSi1-w-x-and-z)O2, where M is at least one metal of valency +3 selected from among Al, B, Ga, Fe, Cr, and combinations thereof; w is a molar fraction of M having a value between 0 and 2(x+y+z); x is a molar fraction of titanium having a value between 0 and 0.06; y is a molar fraction of tin having a value between 0 and 0.06; z is a molar fraction of zirconium having a value between 0 and 0.064, and wherein at least one of the three values "x", "y" or "z" differs from zero. In the present invention it is preferable for the crystalline microporous catalyst to have pores of at least 0.52 nm and a crystalline structure having an x-ray diffractogram corresponding to a beta zeolite.
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Page/Page column 7
(2012/11/13)
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- PRODUCTION OF MYRTANAL FROM BETA-PINENE EPOXIDE
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The present invention refers to a process for the production of myrtanal from β-pinene epoxide that comprises at least of putting this epoxide in contact with a microporous and crystalline catalyst with pores of a diameter of at least 0.52 nm with an empirical formula for the calcinated and dehydrated form of [in-line-formulae]Hw(MwTixSnyZrzSi1-w-x-y-z)O2 [/in-line-formulae]whereM is at least a metal with valence+3 selected from Al, B, Ga, Fe, Cr and combinations of these;w is a molar fraction of M with a value of between 0 and 2(x+y+z);x is a molar fraction of titanium and has a value of between 0 and 0.06;y is a molar fraction of tin and has a value of between 0 and 0.06;z is a molar fraction of zirconium and has a value of between 0 and 0.06;and where at least one of the three values “x”, “y” or “z” is different from zero. In the present invention, the microporous and crystalline catalyst preferably has pores of at least 0.52 nm and has a crystalline structure with an X-ray diffractogram of a zeolite beta.
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Page/Page column 5-6
(2013/02/28)
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- Lipophilic constituents from aerial and root parts of Mercurialis perennis L
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Introduction - Dog's mercury (Mercurialis perennis L.) is a perennial herb used in remedies for medicinal purposes. The plant is supposed to contain potentially active substances but its constituents have only been rarely studied. Objective - Detailed studies on the phytochemical composition are of great interest to broaden the knowledge on the chemotaxonomy and pharmacognosy of M. perennis. Methodology - Chloroform and hexane extracts from roots and aerial parts were investigated using GC/MS and LC/MS. Results - The whole plant exhihited a broad spectrum of structurally diverse constituents, mainly alkaloids, terpenes, sterols and simple aromatic compounds. Closer inspection of the piperidine alkaloid hermidin revealed its inherent instability towards air oxygen. To obtain quantitative data on these alkaloids the synthesis of the more stable reference compound 4-methoxy-1-methylpyridine-2,6(1H,3H)-dione (MMPD) was required. In this study, MMPD was detected for the fi rst time as a genuine compound in Mercurialis. Hermidine quinone and hermidin dimers originating from hermidin via a free anionic radical reaction were also confi rmed by GC/MS. Moreover, volatile compounds such as benzylalcohol, 2-phenylethanol, 4-methoxy- and 3,4-dimethoxyphenol, (-)-cis- and (+)-trans-myrtanol, (-)-cis-myrtanal as well as squalene were predominantely present in Mercurialis roots. In contrast, aerial parts mainly contained phytol derivatives, sterols and tocopherols. By changing solvent polarity, lipid and wax-containing fractions were obtained. LC/MS-studies on hexane extracts showed the presence of several mixed triglycerides constituted by linolenic, linoleic, oleic, stearic and palmitic acids, as well as lutein, carotenes and pheophytins. Conclusions - The phytochemical data presented complement our knowledge on the rarely studied plant M. perennis and may broaden its use in future phytotherapy. Copyright
- Lorenz, Peter,Hradecky, Marc,Berger, Melanie,Bertrams, Julia,Meyer, Ulrich,Stintzing, Florian C.
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experimental part
p. 234 - 245
(2011/11/06)
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- Convenient preparation of carbonyl compounds from 1,2-diols utilizing Mitsunobu conditions
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1,1-Disubstituted 1,2-diols are efficiently converted into carbonyl compounds by reaction with triphenylphosphine and diethyl azodicarboxylate. (C) 2000 Elsevier Science Ltd.
- Barrero, Alejandro F.,Alvarez-Manzaneda, Enrique J.,Chahboun
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p. 1959 - 1962
(2007/10/03)
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- A convenient, efficient method for conjugate reductions using catalytic quantities of Cu(I)
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Exposure of enones and enals to either Bu3SnH or PhSiH3 in the presence of ≤ 5 mol % [(Ph3P)CuH]6 leads to products of 1,4-hydride delivery in good yields.
- Lipshutz, Bruce H.,Keith, John,Papa, Patrick,Vivian, Randall
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p. 4627 - 4630
(2007/10/03)
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- Selective aerobic oxidation of primary alcohols catalyzed by a Ru(PPh3)3Cl2/hydroquinone system
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Aerobic oxidation of primary alcohols to aldehydes was efficiently performed using a Ru(PPh3)3Cl2/hydroquinone system under atmospheric oxygen at 60 °C. A primary alcohol even in the presence of a secondary one was selectively oxidized to the corresponding aldehyde in high yield.
- Hanyu, Atsushi,Takezawa, Eiichiro,Sakaguchi, Satoshi,Ishii, Yasutaka
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p. 5557 - 5560
(2007/10/03)
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- One-pot conversion of olefins to carbonyl compounds by hydroboration/NMO-TPAP oxidation
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An efficient method to oxidize an olefin to the less substituted carbonyl compound is described. This new methodology utilizes borane dimethyl sulfide followed by tetrapropylammonium perruthenate N-methylmorpholine N-oxide to oxidize the resulting alkylborane.
- Yates, Matthew H.
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p. 2813 - 2816
(2007/10/03)
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- Catalytic Reaction. 1. Catalytic 1,4-Hydrogenation of α,β-Unsaturated Aldehydes and Ketones using SC-1 Nickel Boride
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Ex-situ generated Sc-1 nickelboride (SC-1 Ni2B), prepared by refluxing nickel chloride and sodium borohydride in methanol, is used in the selective 1,4-hydrogenation of α,β-unsaturated ketones and aldehydes at one atmospheric pressure.Previous studies of in-situ generated Ni2B have had the disadvantage of the undesirable side reaction of sodium borohydride with the various functional groups.In contrast, our catalyst cleanly gives the corresponding saturated aldehyde or ketone with no detectable amounts of saturated alcohol.Furthermore, the degree of substitution of the double bond plays a significant role in the rate of hydrogenation.While unsaturated carbonyl compounds containing di- and tri- substituted duoble bonds are readily hydrogenated, tetrasubstituted double bond containing carbonyl compounds are highly unreactive.
- Belisle, Christopher M.,Young, Yvette M.,Singaram, Bakthan
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p. 5594 - 5598
(2007/10/02)
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- A Selective and Efficient Method for Alcohol Oxidations Mediated by N-Oxoammonium Salts in Combination with Sodium Bromite
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The oxidation of primary and secondary alcohols leading to aldehydes, carboxylic acids, and ketones has been carried out in a N-oxoammonium salts-NaBrO2 system.Sodium bromite as a stoichiometric oxidizing reagent activates N-oxyl compounds (recycling catalysts) to their N-oxoammonium salts in a weakly basic medium, which oxidize primary hydroxyl groups preferentially rather than secondary ones to the corresponding aldehydes.Calcium hypochlorite is used as an alternative terminal oxidant in the same media.The procedure, applicable to the selective formation of γ- and δ-lactones, β-hydroxy aldehydes, and 2-acetoxy ketones, is advantageous in terms of reagent cost, safety, and ease of operation.
- Inokuchi, Tsutomo,Matsumoto, Sigeaki,Nishiyama, Tokio,Torii, Sigeru
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p. 462 - 466
(2007/10/02)
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