- Reegioselective Alkylation of Lithium Enolates Derived from 2-Heptanone
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The benzylation and n-butylation of the kinetic enolate mixture derived from 2-heptanone has been studied in DME in the absence and in the presence of lithium ion complexing agents (triglyme, benzo-14-crown-4, DMF (neat), DMF, and HMPA).
- Liotta, Charles L.,Caruso, Thomas C.
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Read Online
- Optimization studies on the hydro-acylation of 1-alkenes to α-methylketones using a homogeneous palladium/Josiphos catalyst
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The effect of process conditions (temperature, partial pressures of CO and H2) on the product selectivity and ee of the palladium-catalysed asymmetric hydro-acylation of 1-pentene in dichloromethane with the chiral Josiphos ligand (SL-J008-1, L1) was investigated. The highest ee value (73%) for the desired product 4-methyl-5-decanone (1) was obtained at the lowest temperature in the range (30 °C). The selectivity for 1 was between 12 and 20 mol % at 30 °C, though considerably higher at 90 °C (59 mol %). Statistical modeling was applied to quantify the influence of the process conditions on the product selectivity and ee.
- Heeres, Hans,Minnaard, Adri J.,Hessen, Bart,Heeres, Hero J.
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Read Online
- Process for the preparation of higher order alkanones, preferably 6 -undecanone and derivatives thereof
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The present invention relates to a method of producing higher alkanones, preferably 6 undecanone., from ethanol and/or acetate, the method comprising (a) contacting the ethanol and/or acetate with at least one microorganism capable of carrying out carbon chain elongation to produce hexanoic acid and/or an ester thereof from the ethanol and/or acetate; (b) extracting the hexanoic acid and/or ester thereof from (a) using at least one extractant in an aqueous medium, wherein the extractant comprises at least one alkyl-phosphine oxide and at least one alkane comprising at least 12 carbon atoms; or at least one trialkylamine and at least one alkane comprising at least 12 carbon atoms; and (c) contacting the extracted hexanoic acid and/or ester thereof from (b) with at least one ketonization catalyst and eventually a further alkanoic acid comprising 1 to 22 carbon atoms under suitable reaction conditions for chemical ketonization of hexanoic acid and eventually the further alkanoic acid to a higher alkanone, preferably 6-undecanone.
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Paragraph 0176-0181
(2021/08/05)
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- METHOD FOR PRODUCING HIGHER LINEAR FATTY ACIDS OR ESTERS
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The present invention relates to a method of producing linear fatty acids comprising 7 to 28 carbon atoms or esters thereof using a combined biotechnological and chemical method. In particular, the present invention relates to a method of producing dodecanoic acid (i.e. lauric acid), via higher alkanones, preferably 6-undecanone.
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Page/Page column 33-33
(2021/11/26)
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- CATALYST FOR PRODUCING ALIPHATIC KETONES FROM FERMENTED PRODUCT OF BIOMASS, AND METHOD FOR PRODUCING SAME
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The present disclosure discloses: a bifunctional Cu/Ce—Zr-based catalyst suitable for reacting a ketone and alcohol which are contained in a fermented product of biomass and have a low molecular weight, and converting same into an aliphatic ketone having an increased carbon number; a method for producing the catalyst; and a method for producing a fuel-range aliphatic ketone, such as gasoline and air fuel, by using the catalyst.
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Paragraph 0154-0162
(2019/12/06)
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- A Redox Strategy for Light-Driven, Out-of-Equilibrium Isomerizations and Application to Catalytic C-C Bond Cleavage Reactions
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We report a general protocol for the light-driven isomerization of cyclic aliphatic alcohols to linear carbonyl compounds. These reactions proceed via proton-coupled electron-transfer activation of alcohol O-H bonds followed by subsequent C-C β-scission of the resulting alkoxy radical intermediates. In many cases, these redox-neutral isomerizations proceed in opposition to a significant energetic gradient, yielding products that are less thermodynamically stable than the starting materials. A mechanism is presented to rationalize this out-of-equilibrium behavior that may serve as a model for the design of other contrathermodynamic transformations driven by excited-state redox events.
- Ota, Eisuke,Wang, Huaiju,Frye, Nils Lennart,Knowles, Robert R.
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supporting information
p. 1457 - 1462
(2019/01/25)
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- IONIZABLE CATIONIC LIPID FOR RNA DELIVERY
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What is described is a compound of formula I consisting of a compound in which R1 is a branched chain alkyl consisting of 10 to 31 carbons; R2 is a linear alkyl, alkenyl, or alkynyl consisting of 2 to 20 carbons; L1 and L2 are the same or different, each a linear alkylene of 1 to 20 carbons or a linear alkenylene of 2 to 20 carbons; X1 is S or O; R3 is a linear or branched alkylene consisting of 1 to 6 carbons; and R4 and R5 are the same or different, each a hydrogen or a linear or branched alkyl consisting of 1 to 6 carbons; or a pharmaceutically acceptable salt thereof.
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- IONIZABLE CATIONIC LIPID FOR RNA DELIVERY
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What is described is a compound of formula I consisting of a compound in which R1 is a branched chain alkyl consisting of 10 to 31 carbons;R2 is a linear alkyl, alkenyl, or alkynyl consisting of 2 to 20 carbons, or a branched chain alkyl consisting of 10 to 31 carbons;L1 and L2 are the same or different, each a linear alkane of 1 to 20 carbons or a linear alkene of 2 to 20 carbons;X1 is S or O;R3 is a linear or branched alkylene consisting of 1 to 6 carbons; andR4 and R5 are the same or different, each a hydrogen or a linear or branched alkyl consisting of 1 to 6 carbons; or a pharmaceutically acceptable salt thereof.
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- Cerium oxide as a catalyst for the ketonization of aldehydes: Mechanistic insights and a convenient way to alkanes without the consumption of external hydrogen
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The ketonization of aldehydes joins two molecules, with n carbon atoms each, to a ketone with 2n - 1 carbon atoms. When employing cerium oxide as a catalyst with nano-sized crystals (15 nm) the ketone can be obtained in almost 80% yield. In addition, other ketones are observed so that the total ketone selectivity reached almost 90%. Water is consumed during the reaction when the aldehyde is oxidized to the corresponding carboxylic acid, which is established as a reaction intermediate, co-producing hydrogen. Consequently, water has to be co-fed in the reaction to enhance the reaction rate and to improve the catalyst stability with time on stream. In contrast to zirconium oxide which possesses catalytic activity for the aldol condensation liberating water, with cerium oxide water is not abundant on the surface and the reaction kinetics show that the reaction rate depends on the concentration of the water in the gas-phase, in addition to the dependence on the gas-phase concentration of the aldehyde. The liberated hydrogen can be consumed in the hydrodeoxygenation of the ketone product. Doing so, when starting from heptanal, a biomass derived aldehyde, an alkane mixture was obtained with almost 90% diesel content. For the whole cascade reaction with five single steps no reagents are necessary and the only by-product is one molecule of innocuous carbon dioxide (related to two molecules of aldehyde). This shows that cerium oxide possesses a big potential to convert biomass derived aldehydes into biofuels in a very sustainable way.
- Orozco, Lina M.,Renz, Michael,Corma, Avelino
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p. 1555 - 1569
(2017/05/10)
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- Methods to produce fuels
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The present disclosure generally relates to the catalytic conversion of alcohols into hydrocarbon ketones suitable for use as fuels. More specifically, the present disclosure relates to the catalytic conversion of a mixture of isopropanol-butanol-ethanol (IBE) or acetone-butanol-ethanol (ABE), into ketones suitable for use as fuels. The ABE or IBE mixtures may be obtained from the fermentation of biomass or sugars.
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Page/Page column 54; 55
(2018/02/28)
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- ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics
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Herein, we present work on the catalyst development and the kinetics of acetone-butanol-ethanol (ABE) condensation. After examining multiple combinations of metal and basic catalysts reported in the literature, Cu supported on calcined hydrotalcites (HT) was found to be the optimal catalyst for the ABE condensation. This catalyst gave a six-fold increase in reaction rates over previously reported catalysts. Kinetic analysis of the reaction over CuHT and HT revealed that the rate-determining step is the C?H bond activation of alkoxides that are formed from alcohols on the Cu surface. This step is followed by the addition of the resulting aldehydes to an acetone enolate formed by deprotonation of the acetone over basic sites on the HT surface. The presence of alcohols reduces aldol condensation rates, as a result of the coverage of catalytic sites by alkoxides.
- Goulas, Konstantinos A.,Gunbas, Gorkem,Dietrich, Paul J.,Sreekumar, Sanil,Grippo, Adam,Chen, Justin P.,Gokhale, Amit A.,Toste, F. Dean
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p. 677 - 684
(2017/02/26)
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- Carbon–Carbon Bond Formation and Hydrogen Production in the Ketonization of Aldehydes
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Aldehydes possess relatively high chemical energy, which is the driving force for disproportionation reactions such as Cannizzaro and Tishchenko reactions. Generally, this energy is wasted if aldehydes are transformed into carboxylic acids with a sacrificial oxidant. Here, we describe a cascade reaction in which the surplus energy of the transformation is liberated as molecular hydrogen for the oxidation of heptanal to heptanoic acid by water, and the carboxylic acid is transformed into potentially industrially relevant symmetrical ketones by ketonic decarboxylation. The cascade reaction is catalyzed by monoclinic zirconium oxide (m-ZrO2). The reaction mechanism has been studied through cross-coupling experiments between different aldehydes and acids, and the final symmetrical ketones are formed by a reaction pathway that involves the previously formed carboxylic acids. Isotopic studies indicate that the carboxylic acid can be formed by a hydride shift from the adsorbed aldehyde on the metal oxide surface in the absence of noble metals.
- Orozco, Lina M.,Renz, Michael,Corma, Avelino
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p. 2430 - 2442
(2016/10/24)
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- Fragment Couplings via CO2 Extrusion-Recombination: Expansion of a Classic Bond-Forming Strategy via Metallaphotoredox
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In this study we demonstrate that molecular fragments, which can be readily coupled via a simple, in situ RO-C=OR bond-forming reaction, can subsequently undergo metal insertion-decarboxylation-recombination to generate Csp2-Csp3 bonds when subjected to metallaphotoredox catalysis. In this embodiment the conversion of a wide variety of mixed anhydrides (formed in situ from carboxylic acids and acyl chlorides) to fragment-coupled ketones is accomplished in good to high yield. A three-step synthesis of the medicinal agent edivoxetine is also described using this new decarboxylation-recombination protocol.
- Le, C. Chip,MacMillan, David W. C.
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supporting information
p. 11938 - 11941
(2015/10/06)
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- Ketonization of hexanoic acid to diesel-blendable 6-undecanone on the stable zirconia aerogel catalyst
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The ketonization of hexanoic acid, which can be prepared by the fermentation of sugars, was performed in an effort to obtain the diesel-blendable high-carbon-number ketone 6-undecanone in this study. Based on observations of the leaching of highly active base catalysts, magnesium oxide and manganese oxide, the stable amphoteric solid catalyst zirconia was selected for the acid-rich reaction environment. A high-surface-area zirconia aerogel was prepared, which successfully ketonized hexanoic acid to 6-undecanone with high conversion, 72.3%, and high selectivity, 92.6%. The further optimization of the porous structures of zirconia led to possibly improved mass transfer with approximately 35 nm of pores, which improved the catalytic activity of zirconia.
- Lee, Yunsu,Choi, Jae-Wook,Suh, Dong Jin,Ha, Jeong-Myeong,Lee, Chang-Ha
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p. 288 - 293
(2015/10/20)
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- METHOD FOR THE PURPOSE OF A CATALYTIC CONDENSATION OR COUPLING
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The invention relates to a method for catalytically condensing organic compounds containing at least one oxo and/or hydroxyl function into CH acidic compounds and/or coupling said organic compounds to the CH acidic compounds in the presence of a catalyst which comprises an active carbon substrate provided with a metal. The method is suitable in particular for generating higher alcohols, aldehydes, ketones, and/or alkanes as well as mixtures thereof.
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Paragraph 0215-0222
(2014/12/09)
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- Direct α-alkylation of ketones with alcohols in water
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The direct α-alkylation of ketones with alcohols has emerged as a new green protocol to construct C-C bonds with H2O as the sole byproduct. In this work, a very simple and convenient Pd/C catalytic system for the direct a-alkylation of ketones with primary alcohols in pure water is developed. Based on this catalytic system, aqueous mixtures of dilute acetone, 1-butanol, and ethanol (mimicking ABE fermentation products) can be directly transformed into C5-C11 or longer-chain ketones and alcohols, which are precursors to fuels.
- Xu, Guoqiang,Li, Qiong,Feng, Jiange,Liu, Qiang,Zhang, Zuojun,Wang, Xicheng,Zhang, Xiaoyun,Mu, Xindong
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p. 105 - 109
(2014/03/21)
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- α-alkylation of ketones by trialkylamines under heterogeneous Pd/C catalysis
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Ketones are regioselectively α-alkylated with trialkylamines in toluene at 120 °C in the presence of Pd/C.
- Yoon, Il Chul,Kim, Tae Gyun,Cho, Chan Sik
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p. 1890 - 1892
(2014/05/06)
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- METHOD TO CONVERT FERMENTATION MIXTURE INTO FUELS
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The present disclosure provides methods to produce ketones suitable for use as fuels and lubricants by catalytic conversion of an acetone-butanol-ethanol (ABE) fermentation product mixture that can be derived from biomass.
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Page/Page column 73-74
(2013/02/27)
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- Integration of chemical catalysis with extractive fermentation to produce fuels
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Nearly one hundred years ago, the fermentative production of acetone by Clostridium acetobutylicum provided a crucial alternative source of this solvent for manufacture of the explosive cordite. Today there is a resurgence of interest in solventogenic Clostridium species to produce n-butanol and ethanol for use as renewable alternative transportation fuels. Acetone, a product of acetone-n-butanol-ethanol (ABE) fermentation, harbours a nucleophilic α-carbon, which is amenable to C-C bond formation with the electrophilic alcohols produced in ABE fermentation. This functionality can be used to form higher-molecular-mass hydrocarbons similar to those found in current jet and diesel fuels. Here we describe the integration of biological and chemocatalytic routes to convert ABE fermentation products efficiently into ketones by a palladium-catalysed alkylation. Tuning of the reaction conditions permits the production of either petrol or jet and diesel precursors. Glyceryl tributyrate was used for the in situ selective extraction of both acetone and alcohols to enable the simple integration of ABE fermentation and chemical catalysis, while reducing the energy demand of the overall process. This process provides a means to selectively produce petrol, jet and diesel blend stocks from lignocellulosic and cane sugars at yields near their theoretical maxima.
- Anbarasan, Pazhamalai,Baer, Zachary C.,Sreekumar, Sanil,Gross, Elad,Binder, Joseph B.,Blanch, Harvey W.,Clark, Douglas S.,Dean Toste
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p. 235 - 239
(2013/01/15)
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- A new property of geminal bishydroperoxides: Hydrolysis with the removal of hydroperoxide groups to form a ketone
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A new property of geminal bishydroperoxide was discovered: the ability to hydrolyze in acid medium in the presence of hydrogen peroxide with the formation of ketones. The most resistant to hydrolysis are the cyclic C 6-bishydroperoxydes: at room temperature within one day they are practically not hydrolyzed; less stable is bishydroperoxycycloheptane (C 7): in a day its one fifth part is hydrolyzed. Bishydroperoxydes with the cycles of C8 and C12 for the same time hydrolyzed to 80 and 90% respectively. Of the two linear bishydroperoxydes, 2,2-dihydroperoxydecane, with sterically unhindered center, is more resistant to hydrolysis than 6,6-dihydroperoxyundecane. Pleiades Publishing, Ltd., 2010.
- Terent'ev,Krivykh,Krylov,Ogibin, Yu. N.,Nikishin
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experimental part
p. 1667 - 1671
(2011/02/18)
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- Thermal retro-aldol reaction using fluorous ether F-626 as a reaction medium
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A high-boiling, fluorous-organic hybrid ether, F-626, was tested for use in thermal retro-aldol reactions and found to be an excellent reaction medium in view of the ease of separation from the product by fluorous/organic biphasic treatment. The recovered F-626 can be readily reused for subsequent runs.
- Fukuyama, Takahide,Kawamoto, Takuji,Okamura, Takahiro,Denichoux, Aurelien,Ryu, Ilhyong
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experimental part
p. 2193 - 2196
(2010/10/21)
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- One-pot reductive cleavage of exo-olefin to methylene with a mild ozonolysis-Clemmensen reduction sequence
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A one-pot exo-olefin reductive cleavage was for the first time developed. The reaction could proceed under a mild condition avoiding the use of hazardous and expensive reagents. Meanwhile, a TMSCl-mediated Clemmensen reduction in alcoholic solvent was also examined.
- Xu, Shu,Toyama, Takayuki,Nakamura, Jun,Arimoto, Hirokazu
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scheme or table
p. 4534 - 4537
(2010/10/02)
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- Catalytic coupling of carboxylic acids by ketonization as a processing step in biomass conversion
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Carboxylic acids, common intermediate products in biomass conversion processes, can be converted into ketones via ketonization reactions over a ceria-zirconia catalyst. Reaction kinetics studies were carried out using hexanoic acid, as a representative ca
- Gaertner, Christian A.,Serrano-Ruiz, Juan Carlos,Braden, Drew J.,Dumesic, James A.
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experimental part
p. 71 - 78
(2009/12/01)
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- Recyclable palladium catalyst for highly selective α alkylation of ketones with alcohols
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(Chemical Equation Presented) An air-stable, heterogeneous, and recyclable catalyst composed of palladium nanoparticles entrapped in aluminum hydroxide was applied to a highly selective α alkylation. A wide range of aliphatic and aromatic ketones and primary alcohols were coupled to prepare enones in an O2 atmosphere and ketones in an argon atmosphere (see scheme).
- Kwon, Min Serk,Kim, Namdu,Seo, Seong Hyeok,Park, In Soo,Cheedrala, Ravi Kumar,Park, Jaiwook
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p. 6913 - 6915
(2007/10/03)
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- Catalytic ketonisation over oxide catalysts. Part XI*. Cross-ketonisation of esters of aliphatic and aromatic acids
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The cross-ketonisation of a mixture of ethyl acetate and ethyl benzoate under flow conditions has been studied over 20wt%MO2/Al 2O3 (M = Mn, Ce or Zr) catalysts, at 673-723 K. High conversions of aromatic ester up to 98% and moderate yields of acetophenone (2/Al2O3 catalyst was the least selective. In its presence, the yield of styrene (34%) exceeded that of acetophenone (31%). Unexpectedly, pure Al2O3 support exhibited the highest selectivity and moderate activity, at 723 K the yield as high as 51% of acetophenone was noted. The transformations of mixtures of various ethyl alkanoates with ethyl benzoate over alumina have been studied. In the case of straight-chain aliphatic esters, the yields of the corresponding 1-phenyl-1-alkanones were in the range of 41-51%. The presence of a methyl group in the α position of the ester (isobutyrate) reduced the yield of ketone strongly (11%); two methyl groups (pivalate) completely inhibited the reaction. The reactivity of a series of alkyl acetates was also studied in the cross-ketonisation reaction with ethyl benzoate over alumina. It has been found that secondary and tertiary alkyl acetates were slightly more selective than their primary counterparts due to the absence of products of transesterification. For these esters at 723 K the yields of acetophenone were in the range of 64-67%. The cross-ketonisation of a mixture of ethyl acetate with substituted ethyl benzoates led to the corresponding derivatives of acetophenone. It has been found that the position of the substituent in the benzene ring plays a crucial role in the reactivity of the ester and determines the extent of yield of the product. The highest yield of ketone (62%) was observed at 723 K for 3-methylacetophenone. 2-Methylacetophenone was formed with low yields (10%) in the whole range of reaction temperatures, probably due to steric effect in the ortho position. At 698 K the maximum yield of 4-methylacetophenone (27%) was attained. The ketonisation of ethyl acetate with ethyl esters of 4-t-butyl- and 4-chlorobenzoic acids led to moderate yields (24-27%) of 4-t-butyl- and 4-chloroacetophenone, respectively.
- Glinski,Koscik,Jerzak,Synoradzki
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p. 995 - 1001
(2007/10/03)
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- Facile oxidative conversion of alcohols to esters using molecular iodine
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A simple, efficient, and high-yield procedure for the oxidative conversion of alcohols to various types of esters and ketones, with molecular iodine and potassium carbonate was successfully carried out.
- Mori, Naoshi,Togo, Hideo
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p. 5915 - 5925
(2007/10/03)
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- Electrooxidation of alcohols in an N-Oxyl-immobilized poly(ethylene-co- acrylic acid)/water disperse system
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The electrooxidation of alcohols in a disperse system with N-oxyl-immobilized polymer particles (PE-co-AA-N-Oxyl), prepared from poly(ethylene-co-acrylic acid) (PE-co-AA-CO2H), as a disperse phase and an aqueous saturated NaHCO3 containing 20 wt % NaBr as a disperse medium was successfully performed in a simple beaker-type undivided cell under constant-current conditions. The electrooxidation of alcohols proceeded in a similar manner by the use of PE-co-AA-CO2H as a disperse phase, though the current efficiency decreased in some extent. Protection of most of the carboxylic acid moieties on the surface of PE-co-AA-CO2H by esterification or amidation resulted in significant decrease of the product yields, suggesting that the carboxylic acid moieties on the surface of PE-co-AA-CO2H would also act as a mediator for the electrooxidation of alcohols. Both the recovered PE-co-AA-W-Oxyl and the aqueous solution were used repeatedly for the electrooxidation of alcohols, thereby offering a formally closed system for the electrooxidation of alcohols.
- Tanaka, Hideo,Kubota, Jun,Miyahara, Seiji,Kuroboshi, Manabu
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p. 1677 - 1684
(2007/10/03)
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- Catalytic ketonisation over oxide catalysts. Part IX. Single step synthesis of aliphatic saturated and unsaturated C11 - C 13 ketones from carboxylic acids
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Metameric undecan-x-ones (x = 2-6), dodecan-y-ones (y = 2-5), tridecan-z-ones (z = 4-7) and two unsaturated aliphatic ketones were prepared by vapor phase ketonisation of the appropriate monocarboxylic acids in the presence of 20 wt% MnO2/Al2O3 catalyst under flow conditions. The ketones were obtained in yields between 48 and 89% in a multigram scale (80-250 g). Their physical and spectral data have been determined.
- Glinski,Gibka
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p. 299 - 302
(2007/10/03)
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- Unsymmetrical unsaturated ketones from lactones and carboxylic acids in one step
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A one-step transformation of γ- and δ-(spiro)lactones into γ,δ- and δ,ε-unsaturated ketones in the presence of carboxylic acids in the vapor phase at 400° over a supported manganese catalyst is reported for the first time. The scope of this new transformation is exemplified with a series of lactones, and a mechanistic rationale is proposed.
- Giersch, Wolfgang,Naef, Ferdinand
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p. 1704 - 1710
(2007/10/03)
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- The oxidation of alcohols in N-oxyl-immobilized silica gel/aqueous NaOCl disperse systems. A prominent access to a column-flow system
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The oxidation of alcohols was performed successfully in a disperse system with N-oxyl-adsorbed or immobilized silica gel as a disperse phase and aqueous NaOCl as a disperse medium. In the disperse system, the oxidation of sec-alcohols afforded the corresponding ketones, while prim-alcohols were oxidized to aldehydes and/or carboxylic acids depending on their structures and reaction conditions. The N-oxyl-immobilized silica gel was recovered and repeatedly used without a significant change in the product yields. A column-flow system was also investigated for the oxidation of alcohols by use of a newly devised column packed with the N-oxyl-immobilized silica gel.
- Tanaka, Hideo,Chou, Jingyu,Mine, Machiko,Kuroboshi, Manabu
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p. 1745 - 1755
(2007/10/03)
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- PROCESS FOR THE CONVERSION OF CARBOXYLIC ACIDS TO KETONES
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Disclosed is a process for the preparation of ketones by contacting one or more carboxylic acids with a niobium catalyst at elevated temperatures. The process includes the use of a modified base-exchanged niobium catalyst that is particularly useful for the production of cyclopropyl ketones such as cyclopropyl methyl ketone from cyclopropanecarboxylic acid and acetic acid.
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- Ruthenium-catalyzed regioselective α-alkylation of ketones with primary alcohols
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Ketones are regioselectively alkylated with an array of primary alcohols in dioxane at 80°C in the presence of a catalytic amount of a ruthenium catalyst together with KOH and a hydrogen acceptor.
- Cho, Chan Sik,Kim, Bok Tae,Kim, Tae-Jeong,Chul Shim, Sang
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p. 7987 - 7989
(2007/10/03)
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- Process for the conversion of carboxylic acids to ketones
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Disclosed is a process for the preparation of ketones by contacting one or more carboxylic acids with a niobium catalyst at elevated temperatures. The process includes the use of a modified base-exchanged niobium catalyst that is particularly useful for the production of cyclopropyl ketones such as cyclopropyl methyl ketone from cyclopropanecarboxylic acid and acetic acid.
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- Synthesis and antimalarial activity of novel medium-sized 1,2,4,5-tetraoxacycloalkanes
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CsOH- or Ag2O-mediated cycloalkylation of (alkylidene)bisperoxides 3 and 1,n-dihaloalkanes (n = 3-8) provided the corresponding medium-sized 1,2,4,5-tetraoxacycloalkanes 4-8 in moderate yields. Subsequent evaluation of the antimalarial activity of the cyclic peroxides 4-8 in vitro and in vivo revealed that 1,2,6,7-tetraoxaspiro[7.11]nonadecane 4a has considerable potential as a new, inexpensive, and potent antimalarial drug.
- Kim,Nagai,Ono,Begum,Wataya,Hamada,Tsuchiya,Masuyama,Nojima,McCullough
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p. 2357 - 2361
(2007/10/03)
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- C-H and C-C bond activation of primary amines through dehydrogenation and transimination
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Matrix presented Dehydrogenation and subsequent transimination of primary amines offer a new pathway for C-H bond activation, ortho-alkylation, and C-C bond activation to afford a variety of ketones in the reaction of 1-alkene by a cocatalyt system of Rh(I) and 2-amino-3-picoline.
- Jun, Chul-Ho,Chung, Kwan-Yong,Hong, Jun-Bae
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p. 785 - 787
(2007/10/03)
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- Vapor-phase synthesis of symmetric ketone from alcohol over CeO2-Fe2O3 catalysts
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Formation of 3-pentanone via oxidative dimerization of 1-propanol was investigated over CeO2-based solid solution with various metal oxides. An addition of Fe2O3 into CeO2 greatly enhanced the 3-pentanone formation, and both 1-propanol conversion and 3-pentanone selectivity were maximized at Fe content of 20 mol%. It was found that the CeO2-Fe2O3 effectively works as a catalyst for the formation of symmetric ketones such as 3-pentanone, 4-heptanone, 5-nonanone, etc.
- Kamimura, Yoichiro,Sato, Satoshi,Takahashi, Ryoji,Sodesawa, Toshiaki,Fukui, Masahiro
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p. 232 - 233
(2007/10/03)
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- Acylation of aromatic ethers/phenols
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Aromatic ethers/phenols are acylated, characteristically into hydroxy- and/or alkoxyaromatic alkylketones, and in particular, are acylated in the para-position relative to an alkoxy substituent borne by the aromatic nucleus, by reacting/condensing same with an acylation agent, for example acetyl chloride or acetic anhydride, in the presence of a catalytically effective amount of a bismuth halide, or a precursor compound that generates, in situ, a bismuth halide.
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- Cathodic carbonylation. Synthesis of aliphatic aldehydes using an electroreductively generated iron-carbonyl anion
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Alkyl halides are electroreductively coupled with pentacarbonyliron to generate the acyliron complexes. After hydrolytic work-up, these anionic acyl compounds produce aldehydes in good yields. The best results were obtained with the bromide as starting halide. The first step in the formation of acyliron complexes is the direct cathodic reduction of [Fe(CO)5] to the anionic species. Synthetic and mechanistic aspects of the reaction are discussed.
- Yoshida, Kunihisa,Kuwata, Hideki
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p. 1873 - 1877
(2007/10/03)
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- TRANSFORMATION OF ACYLOIN O-ACYL DERIVATIVES TO KETONES USING TETRABUTYLAMMONIUM FLUORIDE-THIOL SYSTEM
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The treatment of acyloin (α-hydroxyketone) O-acyl derivatives with tetrabutylammonium fluoride hydrate (TBAF*xH2O)-1,3-propanedithiol system gave the corresponding ketones.Further, it was found that N-methylmorpholine added could prevent the concomitant of unidentified compounds to give the pure products in high yields.
- Ueki, Masaaki,Okamura, Ayako,Yamaguchi, Jun-ichi
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p. 7467 - 7470
(2007/10/02)
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- A Novel Ru(VII)/Ru(IV) Mediatory System for Electrooxidation of Primary and Secondary Alcohols, Leading to Aldehydes and Ketones
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A soluble Ru(VII)/Ru(IV) redox system in MeCN/H2O(9/1 v/v)-Bu4NOH-(Pt/Pt) was found to be a mild oxidizing method for the electrochemical conversion of primary and secondary alcohols into their corresponding aldehydes and ketones under basic conditions.
- Torii, Sigeru,Yoshida, Akihito
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p. 369 - 370
(2007/10/02)
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- Cathodic Carbonylation of 1-Halogenopentanes
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Reaction conditions for electroreductive conversion of 1-halogenopentane into hexanal using have been investigated in detail.The use of acetonitrile as solvent containing tetraalkylammonium halides or toluene-p-sulfonate and a divided cell gave good results.Under the conditions, the best results were obtained with the bromide as starting halide.
- Yoshida, Kunihisa,Kobayashi, Masaru,Amano, Sei-ichi
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p. 1127 - 1130
(2007/10/02)
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- Indirect Electrooxidation of Alcohols by a Double Mediatory System with Two Redox Couples of +=O>/R2NO. and . or Br+>/Br- in an Organic-Aqueous Two-Phase Solution
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An indirect electrooxidation method for alcohol to aldehyde or ketone conversion has been developed.This method, applicable to chemoselective oxidation, employs two redox couples, consisting of 2,2,6,6-tetramethylpiperidine-1-oxyl derivatives 6 and active bromine species.The former is required for the chemical process and recycled, whereas the latter is to be involved in the electrochemical process.Three chemical events play an important role in this system: (1) the formation of . or Br+> from bromide ion by discharge on the anode in an aqueous solution, (2) the reaction of N-oxyl compounds 6 with active bromine species to generate N-oxoammonium ion 7, and (3) the oxidation of alcohols with 7 in an organic phase.Optimum conditions were established as follows: an aqueous 25percent NaBr solution buffered at pH 8.6 in a binary system, the use of 1-10 mol percent of 4-(benzoyloxy)piperidine derivatives 6, and adjustment of an electric current at 10-100 mA/cm2.The successful applications of the present method to the oxidation of a variety of primary and secondary alcohols including 1,n-diols, giving the corresponding carbonyl compounds, have delineated its synthetic utility.The chemoselective oxidation of a primary hydroxy group in the presence of secondary one has been achieved with a high selectivity by the present procedure.
- Inokuchi, Tsutomu,Matsumoto, Sigeaki,Torii, Sigeru
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p. 2416 - 2421
(2007/10/02)
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- Physico-Chemical Studies on Samarium Soaps in Solid State
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The physico-chemical characteristics of samarium soaps (caproate and caprate) in solid state were investigated by IR, X-ray diffraction and TGA measurements.The IR results releaved that the fatty acids exist in dimeric state through hydrogen bonding and s
- Mehrotra, Krishna N.,Chauhan, Mithlesh,Shukla, Rajeev K.
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p. 1063 - 1068
(2007/10/02)
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- Synthesis of Some New Polynuclear Compounds by Cycloaddition Reaction
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A large number of 7,9-disubstituted derivatives (I) of cyclopentacenaphthylene-8(H)-one and 2,5-disubstituted derivatives (II) of 3,4-diphenylcyclopentadienone have been synthesized by condensing acenaphthaquinone and benzil separately with suitable 1,3-disubstituted propan-2-ones.The 3-(o- and p-methoxytolyl)cyclopentadienones (IX) have been synthesized by Friedel-Crafts reaction of appropriate methyl cresyl ethers and phenacyl chloride.These dienones have been subjected to Diels-Alder reaction with acenaphthylene and a new acetylenic dienophile (V) (whose synthesis is also described in this paper) to yield a large number of polynuclear aromatic compounds having fluoranthene and p-quaterphenyl nuclei, which have been finally characterised by elemental analyses, IR and PMR spectral data.
- Samanta, S. R.,Mukherjee, A. K.
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- DEKETALIZATION INDUCED BY PHENYL DICHLOROPHOSPHATE AND SODIUM IODIDE
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Treatment of ketals with phenyl dichlorophosphate and sodium iodide in refluxing benzene gave rise to ketones.
- Liu, Hsing-Jang,Yu, Shu-Yuan
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p. 1357 - 1362
(2007/10/02)
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- DIRECT CONVERSION OF SILYL ETHERS INTO CARBONYL COMPOUNDS WITH JONES REAGENT IN THE PRESENCE OF POTASSIUM FLUORIDE
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Treatment of silyl ethers with Jones reagent in acetone in the presence of potassium fluoride resulted in the silicon-oxygen bond cleavage and oxidation to give carbonyl compounds directly
- Liu, Hsing-Jang,Han, In-Sup
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p. 759 - 764
(2007/10/02)
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- A HIGHLY EFFICIENT SYNTHETIC ROUTE TO KETONES THROUGH SEQUENTIAL COUPLING REACTIONS OF GRIGNARD REAGENTS WITH S-PHENYL CARBONOCHLORODITHIOATE IN THE PRESENCE OF NICKEL OR IRON CATALYSTS
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The sequential coupling reactions of Grignard reagents with S-phenyl carbonochloridothioate in the presence of nickel(II) or iron(III) catalysts provides a very mild and straightforward route to symmetrical and unsymmetrical aliphatic and aromatic ketones.
- Cardellicchio, C.,Fiandanese, V.,Marchese, G.,Ronzini, L.
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p. 3595 - 3598
(2007/10/02)
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