- Could the energy cost of using supercritical fluids be mitigated by using CO2 from carbon capture and storage (CCS)?
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This article explores the possibility of utilising supercritical CO 2 obtained from carbon capture and storage (CCS) as a solvent and examines the hydrogenation of isophorone to 3,3,5-trimethylcyclohexanone using supercritical CO2 with added N2, CO or H2O to emulate the contaminants expected in CO2 from CCS. None of the impurities appear to cause insuperable problems in the hydrogenation of isophorone when present at concentrations likely to be found in CO2 from CCS. N2 introduces modest changes in phase behaviour at some pressures, while CO and H2O reduce the activity of the catalyst. However, the activity can be largely regained by increasing the reaction temperature.
- Stevens, James G.,Gomez, Pilar,Bourne, Richard A.,Drage, Trevor C.,George, Michael W.,Poliakoff, Martyn
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Read Online
- Water-soluble dendritic architectures with carbohydrate shells for the templation and stabilization of catalytically active metal nanoparticles
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Hyperbranched poly(ethylenimine) (PEI) with amino groups or carbohydrate terminal groups have been used as support materials for metal nanoparticles (i.e., Cu, Ag, Au, and Pt) in water. Various parameters have been optimized, such as pH, concentration of the polymer in solution, and [metal ions]/ [polymer] ratio in order to obtain stable metal nanoparticles with a narrow size distribution. TEM measurements revealed that particles with a diameter as low as 1.4 nm were obtained. An increase of stability was obtained after functionalization of PEI with glycidol, gluconolactone, or lactobionic acid. In the case of Pt the catalytical activity of the corresponding nanoparticles was evidenced.
- Kraemer, Michael,Perignon, Nelly,Haag, Rainer,Marty, Jean-Daniel,Thomann, Ralf,Viguerie, Nancy Lauth-De,Mingotaud, Christophe
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Read Online
- Study on the selective hydrogenation of isophorone
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3,3,5-Trimethylcyclohexanone (TMCH) is an important pharmaceutical intermediate and organic solvent, which has important industrial significance. The selective hydrogenation of isophorone was studied over noble metal (Pd/C, Pt/C, Ir/C, Ru/C, Pd/SiO2, Pt/SiO2, Ir/SiO2, Ru/SiO2), and non-noble metal (RANEY Ni, RANEY Co, RANEY Cu, RANEY Fe, Ni/SiO2, Co/SiO2, Cu/SiO2, Fe/SiO2) catalysts and using solvent-free and solvent based synthesis. The results show that the solvent has an important effect on the selectivity of TMCH. The selective hydrogenation of isophorone to TMCH can be influenced by the tetrahydrofuran solvent. The conversion of isophorone is 100%, and the yield of 3,3,5-trimethylcyclohexanone is 98.1% under RANEY Ni and THF. The method was applied to the selective hydrogenation of isopropylidene acetone, benzylidene acetone and 6-methyl-5-ene-2-heptanone. The structures of the hydrogenation product target (4-methylpentan-2-one, 4-benzylbutan-2-one and 6-methyl-heptane-2-one) were characterized using 1H-NMR and 13C-NMR. The yields of 4-methylpentan-2-one, 4-benzylbutan-2-one and 6-methyl-heptane-2-one were 97.2%, 98.5% and 98.2%, respectively. The production cost can be reduced by using RANEY metal instead of noble metal palladium. This method has good application prospects. This journal is
- Xu, Lei,Sun, Shaoyin,Zhang, Xing,Gao, Haofei,Wang, Wei
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p. 4465 - 4471
(2021/02/03)
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- Gas phase transfer hydrogenation of α, β- unsaturated carbonyl compounds into saturated carbonyl compounds over supported Cu catalysts
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This work aims to produce hydrocinnamaldehyde via selective C[dbnd]C bond hydrogenation of cinnamaldehyde via transfer hydrogenation catalyzed by supported Cu catalysts. The catalytic activity and characterization results demonstrated that conversion of cinnamaldehyde and selectivity to hydrocinnamaldehyde is an integrated result of active Cu metal surface area and nature of support material. In the case of Cu/SiO2 catalysts, the rate of formation of hydrocinnamaldehyde was linearly dependent on the active Cu metal surface area. A maximum rate of formation of hydrocinnamaldehyde 167.82 μmol.g?1.s-1 was obtained at an active Cu metal surface area of 6.1 m2.gcat-1 over 20 wt. % Cu/SiO2 catalyst. While in the case of other supported Cu catalysts (Cu/MgO, Cu/ZrO2 and Cu/γ-Al2O3) along with the active Cu metal surface area, the surface acidity and basicity governed the selectivity of hydrocinnamaldehyde. The rate of formation of hydrocinnamaldehyde followed the trend Cu/SiO2 >Cu/Al2O3 >Cu/MgO > Cu/ZrO2. Unlike Cu/SiO2 catalyst, the competitive adsorption of C[dbnd]C and CO[dbnd] bonds over these (Al2O3, MgO and ZrO2) supported Cu catalysts altered the selectivity of hydrocinnamaldehyde. Cu/SiO2 catalyst was superior in selective C[dbnd]C hydrogenation of α, β-unsaturated carbonyl compounds via transfer hydrogenation. Cyclohexenone, isophorone and crotonaldehyde were selectively converted into their saturated carbonyl compounds.
- K, Saidulu Reddy,Enumula, Siva Sankar,Koppadi, Kumara Swamy,Rao Kamaraju, Seetha Rama,Burri, David Raju
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- Cucurbit[5]uril-mediated electrochemical hydrogenation of α,β-unsaturated ketones
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The potential of cucurbit[5]uril to be used as inverse phase transfer catalyst in electrocatalytic hydrogenation of α,β-unsaturated ketones is illustrated. The interaction behavior among isophorone and cucurbit[5]uril was also investigated using cyclic voltammetry and UV/vis absorption spectroscopy. The results concerning to both techniques revealed an enhancement in the intensity of the absorption peak and also in the current cathodic peak of isophorone in presence of cucurbit[5]uril. This achievement is related to the increase of the isophorone solubility in the medium being an indicative of a host-guest complex formation. The electrochemical hydrogenation of isophorone using cucurbit[5]uril was more efficient than others well-stablish methodologies. Regarding to (R)-(+)-pulegone and (S)-(+)-carvone, the use of cucurbit[5]uril leads to an increase of 17% and 9%, on average, respectively, in the yields when compared to the control reaction. The efficiency of selective C=O bond hydrogenation of 1-acetyl-1-cyclohexene was evaluated. The presence of cucurbit[5]uril increased by 12% the hydrogenations yields of 1-acetyl-1-cyclohexene when compared to the control reaction. In this sense, these results open up an opportunity to carry out electrocatalytic reactions within the cucurbit[5]uril environment.
- Sales, Ayrlane,de Oliveira e Castro, Isabela Andrade,de Menezes, Frederico Duarte,Selva, Thiago Matheus Guimar?es,Vilar, Márcio
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p. 295 - 305
(2019/09/03)
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- Ammonium Tungstate as an Effective Catalyst for Selective Oxidation of Alcohols to Aldehydes or Ketones with Hydrogen Peroxide under Water - A Synergy of Graphene Oxide
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Ammonium tungstate was found to be a facile and efficient catalyst for selective oxidation of alcohols to the corresponding carbonyl compounds with hydrogen peroxide as oxidant. Heterogeneous graphene oxide as acid effectively intensified the transformations and resulted in excellent yields. The use of water as solvent rendered the reactions promising both economically and environmentally.
- Fu, Huihui,Hu, Chuanfeng,Huang, Zhida,Zhou, Jianhao,Peng, Xinhua
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supporting information
p. 447 - 451
(2017/11/27)
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- Iron-Catalyzed Chemoselective Reduction of α,β-Unsaturated Ketones
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An iron-catalyzed chemo- and diastereoselective reduction of α,β-unsaturated ketones into the corresponding saturated ketones in mild reaction conditions is reported herein. DFT calculations and experimental work underline that transfer hydride reduction is a more facile process than hydrogenation, unveiling the fundamental role of the base.
- Lator, Alexis,Gaillard, Sylvain,Poater, Albert,Renaud, Jean-Luc
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supporting information
p. 5770 - 5774
(2018/03/26)
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- Wilkinson-Type Immobilized Catalyst on Diamond Nanoparticles for Alkene Reduction
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The immobilization of heterogeneous catalysts on solid support materials is an important task of current catalytic and materials science research. We report here the development of a diamond nanoparticles-based Wilkinson's type catalyst for the reduction of olefins to saturated hydrocarbons. The strategy is based on the formation of rhodium(I)-modified nanodiamonds (NDs–Rh) using a surface-immobilized catechol phosphane ligand, to which rhodium metal centers can be coordinated. The resulting material was characterized by solid-state NMR spectroscopy, X-ray photoelectron spectroscopy, thermogravimetry, and TEM before testing the catalytic efficiency of the catalyst. Excellent hydrogenation efficiency with yields in the range of 85–99 % could be obtained with these new NDs–Rh catalysts, which showed in addition good recyclability without loss of activity.
- Queffélec, Clémence,Schlindwein, Simon H.,Gudat, Dietrich,Silvestre, Virginie,Rodriguez-Zubiri, Mireia,Fayon, Franck,Bujoli, Bruno,Wang, Qi,Boukherroub, Rabah,Szunerits, Sabine
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p. 432 - 439
(2017/02/15)
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- P-Chirogenic Xantphos Ligands and Related Ether Diphosphines: Synthesis and Application in Rhodium-Catalyzed Asymmetric Hydrogenation
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A series of P-chirogenic Xantphos ligands and related diaryl ether diphosphines have been synthesized by a modification of the well-established Jugé method. The approach consists of the in situ deboranation of the chiral ephedrine-based phosphinite before the P-C coupling takes place. The stereochemical integrity of the stereocenters of the diphosphines during synthesis, long-time storage, and catalytic application was evaluated. In the rhodium-catalyzed asymmetric hydrogenation of isophorone as a model substrate for industrially relevant prostereogenic enones with some of the diphosphines, almost complete conversion, high chemoselectivity, and 96% ee were achieved.
- Holz, Jens,Rumpel, Katharina,Spannenberg, Anke,Paciello, Rocco,Jiao, Haijun,B?rner, Armin
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p. 6162 - 6169
(2017/09/15)
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- The selective hydrogenation of the isophorone is 3, 3, 5 - trimethyl cyclohexanone method (by machine translation)
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The selective hydrogenation of the isophorone is 3, 3, 5 - trimethyl cyclohexanone, isophorone and water will be added after mixing the hydrogen gas after the nano-Pd catalyst, isophorone with hydrogen gas in the reaction under the constant temperature of the cooling after a certain period of time, oil-water phase separation, the oil phase obtained in the 3, 3, 5 - trimethyl cyclohexanone, wherein: nano Pd catalyst preparation method is as follows: with the molten state of the palladium acetate PEG reaction of black are a solid. (by machine translation)
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Paragraph 0018; 0022-0024; 0025-0027; 0028-0030; 0031-0034
(2017/08/27)
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- Modular Bidentate Hybrid NHC-Thioether Ligands for the Stabilization of Palladium Nanoparticles in Various Solvents
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The synthesis of four different bidentate hybrid NHC-thioether ligands is presented. The corresponding palladium nanoparticles are stable in various solvents, depending on the ligand used, and show high chemoselectivity in the hydrogenation of olefins. The solubility of the nanoparticles can be switched multiple times depending on the pH value of the solvent. XPS analysis (which shows a subtle shift in the binding energy) was identified as a convenient tool to establish the binding mode of NHC ligands.
- Rühling, Andreas,Schaepe, Kira,Rakers, Lena,Vonh?ren, Benjamin,Tegeder, Patricia,Ravoo, Bart Jan,Glorius, Frank
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supporting information
p. 5856 - 5860
(2016/05/09)
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- Mild and Selective Catalytic Hydrogenation of the C=C Bond in α,β-Unsaturated Carbonyl Compounds Using Supported Palladium Nanoparticles
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Chemoselective reduction of the C=C bond in a variety of α,β-unsaturated carbonyl compounds using supported palladium nanoparticles is reported. Three different heterogeneous catalysts were compared using 1 atm of H2: 1) nano-Pd on a metal-organic framework (MOF: Pd0-MIL-101-NH2(Cr)), 2) nano-Pd on a siliceous mesocellular foam (MCF: Pd0-AmP-MCF), and 3) commercially available palladium on carbon (Pd/C). Initial studies showed that the Pd@MOF and Pd@MCF nanocatalysts were superior in activity and selectivity compared to commercial Pd/C. Both Pd0-MIL-101-NH2(Cr) and Pd0-AmP-MCF were capable of delivering the desired products in very short reaction times (10-90 min) with low loadings of Pd (0.5-1 mol %). Additionally, the two catalytic systems exhibited high recyclability and very low levels of metal leaching.
- Nagendiran, Anuja,Pascanu, Vlad,Bermejo Gómez, Antonio,González Miera, Greco,Tai, Cheuk-Wai,Verho, Oscar,Martín-Matute, Belén,B?ckvall, Jan-E.
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p. 7184 - 7189
(2016/05/19)
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- Water soluble polymer-surfactant complexes-stabilized Pd(0) nanocatalysts: Characterization and structure-activity relationships in biphasic hydrogenation of alkenes and α,β-unsaturated ketones
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A suitable approach to stabilize palladium nanoparticles in water as a green reaction medium for catalytic hydrogenation reactions is described. Supramolecular self-assemblies, obtained through the mixture of modified polyethyleneimines as amphiphilic polymers and water-soluble ammonium salts as surfactants, were used as efficient protective agents in the synthesis of Pd(0) nanospecies. The size and dispersion of the nanoparticles prepared with these original self-assemblies were characterized by TEM, SAXS and DLS techniques. The performances of the catalysts according to the polymer-surfactant mixtures were investigated in the hydrogenation of alkenes and α,β-unsaturated ketones in pure biphasic water/substrate medium, under mild conditions (room temperature and 1 bar H2). The nanocatalysts showed efficient catalytic activities and selectivity towards C=C bonds. From investigations, the polymer-surfactant complexes act as cooperative protective agents and a pertinent structure-activity relationship was proposed based on the zeta-potential values and the catalytic activity of the resulting colloids.
- Albuquerque, Brunno L.,Denicourt-Nowicki, Audrey,Mériadec, Cristelle,Domingos, Josiel B.,Roucoux, Alain
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p. 144 - 153
(2016/07/06)
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- A 3, 3, 5-trimethyl method for the production of cyclohexanone
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The invention relates to a preparation method of 3,3,5-trimethyl cyclohexanone. The preparation method comprises the following steps: 1. adding isophorone and catalysts to a reaction kettle; 2. stirring and heating; 3. filling hydrogen, exerting pressure and maintaining the heating temperature; 4. preparing 3,3,5-trimethyl cyclohexanone via reaction time. The preparation method has the beneficial effects that a solvent and a cocatalyst are not used in the reaction process, so that 3,3,5-trimethyl cyclohexanone is simple to prepare and easy to separate, and meanwhile, the production cost is saved.
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Paragraph 0019; 0020
(2016/10/07)
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- New biobased tetrabutylphosphonium ionic liquids: Synthesis, characterization and use as a solvent or co-solvent for mild and greener Pd-catalyzed hydrogenation processes
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Phosphonium-based Ionic Liquids (PhosILs) with natural organic derived anions (l-lactate, l-tartrate, malonate, succinate, l-malate, pyruvate, d-glucuronate, d-galacturonate, ferulate, p-coumarate) were easily prepared by acid-base method from tetrabutylphosphonium hydroxide and an excess of the corresponding acid with good yields. Their characterization was realized through classical NMR, IR and elemental analysis techniques; their viscosity and ATG parameters were also determined. These ionic liquids showed good performance and recyclability in the selective Pd-catalyzed hydrogenation of alkenes, polyenes like linoleic acid and enantioselective hydrogenation of unsaturated ketones such as isophorone at room temperature under atmospheric H2 pressure. Furthermore, NMR studies leading to computational calculations were performed to establish easily the composition of the resulting mixture obtained through the hydrogenation of linoleic acid.
- Hayouni, Safa,Robert, Anthony,Ferlin, Nadège,Amri, Hassen,Bouquillon, Sandrine
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p. 113583 - 113595
(2016/12/16)
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- New Route to Stabilize Ruthenium Nanoparticles with Non-Isolable Chiral N-Heterocyclic Carbenes
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Ru nanoparticles (RuNPs) stabilized by non-isolable chiral N-heterocyclic carbenes (NHCs), namely SIDPhNp ((4S,5S)-1,3-di(naphthalen-1-yl)-4,5-diphenylimidazolidine) and SIPhOH ((S)-3-((1S,2R)-2-hydroxy-1,2-diphenylethyl)-1-((R)-2-hydroxy-1,2-diphenylethyl)-4,5-dihydro-3H-imidazoline), have been synthesized through a new procedure that does not require isolation of the free carbenes. The obtained RuNPs have been characterized by state-of-the-art techniques and their surface chemistry has been investigated by FTIR and solid-state MAS NMR upon the coordination of CO, which indicated the presence of free and reactive Ru sites. Their catalytic activity has been tested in various hydrogenation reactions involving competition between different sites, whereby interesting differences in selectivity were observed, but no enantioselectivity.
- Martnez-Prieto, Luis Miguel,Ferry, Anglique,Lara, Patricia,Richter, Christian,Philippot, Karine,Glorius, Frank,Chaudret, Bruno
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p. 17495 - 17502
(2016/01/25)
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- A rhodium triphenylphosphine catalyst for alkene hydrogenation supported on neat superparamagnetic iron oxide nanoparticles
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A phosphonic acid functionalized triphenylphosphine rhodium complex was synthesized and grafted onto neat superparamagnetic iron oxide nanoparticles. The material was investigated by elemental analysis, IR spectroscopy, thermogravimetric analysis, XRD, N2-physisorption analyses, and TEM measurements. The obtained hybrid material could be used as a catalyst for the hydrogenation of alkenes with excellent yields and a broad substrate scope. The catalyst can be reused ten times without any loss of activity. According to the results from X-ray absorption spectroscopy, it is likely that formation of Rh nanoparticles occurs during the reaction.
- Dehe, Daniel,Wang, Lei,Müller, Melanie K.,D?rr, Gunder,Zhou, Zhou,Klupp-Taylor, Robin N.,Sun, Yu,Ernst, Stefan,Hartmann, Martin,Bauer, Matthias,Thiel, Werner R.
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p. 127 - 136
(2015/03/05)
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- Cyclic bent allene hydrido-carbonyl complexes of ruthenium: Highly active catalysts for hydrogenation of olefins
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A new family of ruthenium complexes bearing the carbodicarbene-type ligand "cyclic bent allene" (CBA) have been synthesized from the common precursor RuHCl(CO)(PPh3)3. Complexes were evaluated for catalytic activity in the room-temperature hydrogenation of unactivated olefins and were found to be significantly more active than known ruthenium hydrido-carbonyl phosphine or NHC complexes. In particular, RuH(OSO2CF3)(CO)(SIMes)(CBA) was found to be among the most active hydrogenation catalysts, achieving comparable activity to Crabtree's catalyst in the hydrogenation of unactivated trisubstituted olefins and superior activity in the hydrogenation of styrene derivatives in side-by-side catalytic runs. RuH(OSO2CF3)(CO)(SIMes)(CBA) was also found to be highly active in olefin selective hydrogenation in the presence of a variety of unsaturated functional groups, and can achieve exceptional diastereoselectivity in functional-group-directed hydrogenations at very low catalyst loadings.
- Pranckevicius, Conor,Fan, Louie,Stephan, Douglas W.
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p. 5582 - 5589
(2015/05/13)
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- Catalytic conversion of isophorone to jet-fuel range aromatic hydrocarbons over a MoOx/SiO2 catalyst
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For the first time, jet fuel range C8-C9 aromatic hydrocarbons were synthesized in high carbon yield (~80%) by the catalytic conversion of isophorone over MoOx/SiO2 at atmospheric pressure. A possible reaction pathway was proposed according to the control experiments and the intermediates generated during the reaction.
- Chen, Fang,Li, Ning,Wang, Wentao,Wang, Aiqin,Cong, Yu,Wang, Xiaodong,Zhang, Tao
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supporting information
p. 11876 - 11879
(2015/07/15)
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- Proline-induced enantioselective heterogeneous catalytic hydrogenation of isophorone on basic polymer-supported Pd catalysts
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The mode of enantioselection in the proline-modified asymmetric hydrogenation of isophorone (3,5,5-trimethyl-2-cyclohexenone) on polymer-supported Pd catalysts has been studied. Based on earlier results, polymers of basic nature, such as poly(vinyl-pyridi
- Sch?fer, Christian,Mhadgut, Shilpa C.,Kugyela, Nndor,T?r?k, Marianna,T?r?k, Bla
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p. 716 - 723
(2015/02/19)
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- An efficient ligand free chemoselective transfer hydrogenation of olefinic bonds by palladium nanoparticles in an aqueous reaction medium
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A highly efficient ligand free catalytic system was developed for chemoselective transfer hydrogenation of α,β-unsaturated carbonyl compounds by palladium nanoparticles (PdNPs) in an aqueous reaction medium. The developed methodology offers chemoselective 1,4-reduction of various α,β-unsaturated carbonyl compounds such as carbonyls, amides, esters and nitriles with excellent chemoselectivity and effective catalyst recyclability. This journal is the Partner Organisations 2014.
- Bagal, Dattatraya B.,Bhanage, Bhalchandra M.
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p. 32834 - 32839
(2014/08/18)
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- Chemoselective transfer hydrogenation of α,β-unsaturated carbonyls using palladium immobilized ionic liquid catalyst
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This work reports a simple and highly efficient protocol for chemoselective transfer hydrogenation of α,β-unsaturated carbonyls using immobilized palladium metal-containing ionic liquid as a versatile heterogeneous catalyst with an excellent conversion and chemoselectivity (up to 100 %). The influence of various reaction parameters such as the effect of hydrogen donor, solvent, temperature, and time were studied. The catalyst was recycled for four consecutive cycles without significant loss in the catalytic activity. The developed protocol is more advantageous due to the use of HCOONH4 as a hydrogen source, mild reaction conditions, and simple workup procedure and applicable for a wide range of substrates.
- Patil, Nilesh M.,Sasaki, Takehiko,Bhanage, Bhalchandra M.
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p. 1803 - 1809
(2015/02/19)
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- Palladium on graphene: The in situ generation of a catalyst for the chemoselective reduction of α,β-unsaturated carbonyl compounds
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Palladium-supported graphene oxide has been successfully applied as a catalyst precursor for the selective reduction of α,β-unsaturated carbonyl compounds. Pd nanoparticles were formed during the course of the reduction with only negligible leaching of the Pd species into the reaction mixture.
- Morimoto, Naoki,Yamamoto, Shun-Ichi,Takeuchi, Yasuo,Nishina, Yuta
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p. 15608 - 15612
(2013/09/12)
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- Heterogeneous transfer hydrogenation over mesoporous SBA-15 co-modified by anionic sulfonate and cationic Ru(III) complex
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Via ion-pair electrostatic interactions with sulfonate anions, the phosphine-ligated Ru(III) complex cations of [RuIIICl 4(L)2]+ (L = 1-butyl-2-(diphenylphosphino)-3- methylimidazolium) were successfully immobilized into a sulfonated SBA-15 framework, leading to the formation of the cationic Ru(III) complex and anionic sulfonate co-modified SBA-15 material (referred to as Ru-SO3-SBA-15). This material was characterized by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), N2 adsorption-desorption isotherms, FT-IR, and elemental analysis techniques. As a heterogeneous catalyst, Ru-SO3-SBA-15 exhibited comparable activity and selectivity to the parent homogeneous catalyst [RuIIICl4(L) 2]PF6 in transfer hydrogenation of ketones. However, as a result of the limited durability of Ru-SO3-SBA-15 in strongly alkaline environments at high temperature, the activity of Ru-SO 3-SBA-15 could not be maintained during subsequent recycled uses.
- Chen, Sheng-Jie,You, Hong-Xing,Vo-Thanh, Giang,Liu, Ye
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p. 851 - 858
(2013/07/19)
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- Copper hydride-catalyzed reduction of electron-deficient olefins
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Copper hydride derived from CuF(PPh3)3·2MeOH- bis[(2-diphenylphosphino)phenyl] ethersilane can reduce electron-deficient olefins selectively and efficiently.
- Zheng, Ai-Jun,Shan, Feng-Jun,Li, Zheng-Ning,Li, Zeng-Chang,Jiang, Lan
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p. 1271 - 1276
(2013/07/19)
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- Graphene-supported Pd nanoparticles: Microwave-assisted synthesis and as microwave-active selective hydrogenation catalysts
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Facile synthesis of graphene-supported Pd nanoparticles (NPs) with an average size of 5 nm (Pd/G) was achieved by a microwave-assisted reduction approach; the obtained Pd/G can be very effectively coupled to the microwave field, making it a high-performance catalyst (with turnover frequency (TOF) of 158 465 h-1) for microwave-assisted selective hydrogenation of isophorone at low temperatures. The Royal Society of Chemistry 2013.
- Yang, Jing-He,Ma, Ding
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p. 10131 - 10134
(2013/09/02)
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- Synthesis of an ionic paramagnetic ruthenium(III) complex and its application as an efficient and recyclable catalyst for the transfer hydrogenation of ketones
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A novel ionic complex, bis[1-butyl-2-(diphenylphosphanyl)-3- methylimidazolium]tetrachloridoruthenium(III) hexafluorophosphate (2), has been synthesized and fully characterized. The single-crystal X-ray diffraction analysis showed that 2 is composed of an Ru complex cation and PF 6- anion. The cation has a highly symmetrical Ru-centered octahedron geometry with four Cl atoms in the equatorial plane and two imidazolium-substituted phosphane ligands in the axial positions. It exhibits paramagnetism due to the presence of one unpaired electron in the phosphane-ligated low-spin RuIII complex. Complex 2 exhibited good catalytic performance in the transfer hydrogenation of a wide range of ketones by using alcohols as hydrogen donors. Owing to its high polarity, good thermal stability, and insensitivity to moisture and oxygen, complex 2 could be used in six catalytic cycles in the transfer hydrogenation of acetophenone without any obvious loss of activity. A novel ionic complex 2 containing an RuIII cation and PF6- anion has been synthesized. The Ru III cation possesses ideal octahedral geometry and exhibits paramagnetism due to the presence of one unpaired electron in the phosphane-ligated low-spin RuIII complex. Complex 2 proves to be an efficient and recyclable catalyst for the transfer hydrogenation of ketones with alcohols as hydrogen donors. Copyright
- Zhou, Chengliang,Zhang, Jing,Dakovic, Marijana,Popovic, Zora,Zhao, Xiaoli,Liu, Ye
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experimental part
p. 3435 - 3440
(2012/09/08)
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- Chemoselective hydrogenation of the olefinic bonds using a palladium/magnesium-lanthanum mixed oxide catalyst
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A palladium/magnesium-lanthanum mixed oxide catalyst is found to be an efficient heterogeneous catalyst for the chemoselective hydrogenation of olefinic double bonds in the presence of various functional groups. The catalyst was recovered by centrifugation and reused for several cycles with consistent activity and selectivity. Copyright
- Kantam, Mannepalli Lakshmi,Kishore, Ramineni,Yadav, Jagjit,Sudhakar, Medak,Venugopal, Akula
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supporting information; experimental part
p. 663 - 669
(2012/04/23)
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- Layered double hydroxides supported nano palladium: An efficient catalyst for the chemoselective hydrogenation of olefinic bonds
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Chemoselective hydrogenation of olefinic double bonds in the presence of various functional groups using layered double hydroxides supported nanopalladium (LDH-Pd0) catalyst is described. LDH-Pd0 was recovered quantitatively by simple filtration and reused several times with consistent activity and selectivity.
- Lakshmi, Kantam M.,Parsharamulu,Manorama
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p. 115 - 119
(2013/01/15)
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- Conjugate reduction of α,β-unsaturated carbonyl and carboxyl compounds with poly(methylhydrosiloxane) catalyzed by a silica-supported compact phosphane-copper complex
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A silica-supported, cage-type, compact phosphane (Silica-SMAP) was used for the copper-catalyzed conjugate reduction of α,β-unsaturated carbonyl and carboxyl compounds with poly(methylhydrosiloxane) (PMHS). The heterogeneous catalyst system showed high activity and chemoselectivity, and was easily separable from the reaction mixture after the reaction. Furthermore, the catalyst was reusable without loss of its high catalytic activity or selectivity.
- Kawamorita, Soichiro,Yamazaki, Kenji,Ohmiya, Hirohisa,Iwai, Tomohiro,Sawamura, Masaya
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p. 3440 - 3444
(2013/02/22)
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- Green production of polymer-supported PdNPs: Application to the environmentally benign catalyzed synthesis of cis-3-hexen-1-ol under flow conditions
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Pd nanoparticles generated on gel type ion-exchange resins under catalytic conditions show high activity, selectivity and durability in partial hydrogenation reactions under mild conditions, thus providing a green, low-cost option for fine-chemicals production. The application to the continuous-flow synthesis of the leaf alcohol fragrance cis-3-hexen-1-ol is demonstrated.
- Moreno-Marrodan, Carmen,Barbaro, Pierluigi,Catalano, Massimo,Taurino, Antonietta
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supporting information
p. 12666 - 12669
(2013/01/15)
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- Palladium-supported ionic liquid catalyst (Pd-SH-SILC) immobilized on mercaptopropyl silica gel as a chemoselective, reusable and heterogeneous catalyst for catalytic hydrogenation
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Palladium acetate was immobilized as Pd-SH-SILC (Pd-supported ionic liquid catalyst) in the pores of amorphous mercaptopropyl silica gel with the aid of an ionic liquid [bmim]BF4. The heterogeneous Pd-SH-SILC was effective for catalytic hydrogenation of a variety of olefins at atmospheric pressure and room temperature. It withstood recycling up to 10 times by decantation.
- Hagiwara, Hisahiro,Nakamura, Tomomi,Hoshi, Takashi,Suzuki, Toshio
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scheme or table
p. 1133 - 1137
(2011/06/26)
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- Water-soluble glycodendrimers: Synthesis and stabilization of catalytically active Pd and Pt nanoparticles
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A new water-soluble glycodendrimer containing 9 terminal modified xylose branches was prepared from nona-azide terminated dendrimer by 'click' chemistry. The glycodendrimer was analyzed by 1H, 13C NMR and mass spectroscopy and used to stabilize palladium (PdNPs) and platine (PtNPs) nanoparticles. These DSN are stable in water and were characterized by TEM. The platinum NPs showed a remarkable catalytically activity for olefin hydrogenation in water at room temperature.
- Gatard, Sylvain,Liang, Liyuan,Salmon, Lionel,Ruiz, Jaime,Astruc, Didier,Bouquillon, Sandrine
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experimental part
p. 1842 - 1846
(2011/04/25)
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- A simple borohydride-based method for selective 1,4-conjugate reduction of α,β-unsaturated carbonyl compounds
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Sodium borohydride is used in combination with a heterogeneous palladium catalyst and acetic acid to selectively reduce the carbon-carbon double bonds of various α,β-unsaturated ketones and related compounds. This simple method is most selective when non-polar solvents such as toluene are used. We observed nearly complete conversion and high selectivities using moderate catalyst loadings. The reactions were typically complete in less than 2 h.
- Russo, Alyssa T.,Amezcua, Kerstin L.,Huynh, Vincent A.,Rousslang, Zach M.,Cordes, David B.
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experimental part
p. 6823 - 6826
(2012/01/03)
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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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- Highly conserved progesterone 5β-reductase genes (P5βR) from 5β-cardenolide-free and 5β-cardenolide-producing angiosperms
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Most cardenolides used in the therapy of cardiac insufficiency are 5β-configured and thus the stereo-specific reduction of the Δ4,5-double bond of a steroid precursor is a crucial step in their biosynthesis. This step is thought to be catalysed by progesterone 5β-reductases. We report here on the isolation of 11 progesterone 5β-reductase (P5βR) orthologues from 5β-cardenolide-free and 5β-cardenolide-producing plant species belonging to five different angiosperm orders (Brassicales, Gentianales, Lamiales, Malvales and Solanales). Amino acid sequences of the P5βR described here were highly conserved. They all contain certain motifs qualifying them as members of a class of stereo-selective enone reductases capable of reducing activated CC double bonds by a 1,4-addition mechanism. Protein modeling revealed seven conserved amino acids in the substrate-binding/catalytic site of these enzymes which are all supposed to exhibit low substrate specificity. Eight P5βR genes isolated were expressed in Escherichia coli. Recombinant enzymes reduced progesterone stereo-specifically to 5β-pregane-3,20-dione. The progesterone 5β-reductases from Digitalis canariensis and Arabidopsis thaliana reduced activated CC double bonds of molecules much smaller than progesterone. The specific role of progesterone 5β-reductases of P5βRs in cardenolide metabolism is challenged because this class of enone reductases is widespread in higher plants, and they accept a wide range of enone substrates.
- Bauer, Peter,Munkert, Jennifer,Brydziun, Margareta,Burda, Edyta,Müller-Uri, Frieder,Gr?ger, Harald,Muller, Yves A.,Kreis, Wolfgang
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scheme or table
p. 1495 - 1505
(2010/11/05)
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- NOVEL WOODY ODORANTS
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The present invention relates to novel substituted cyclohexyl monohydric alcohols possessing woody odor which are useful as fragrance materials. The invention also provides method for synthesis of the above compounds. The invention also provides fragrance compositions which utilize the compounds of the invention to impart woody aroma to such compositions. The compounds of the invention have the general formula as under
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- Recombinant Δ4,5-steroid 5 β-reductases as biocatalysts for the reduction of activated C=C-double bonds in monocyclic and acyclic molecules
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It was found that Δ4,5-steroid 5β-reductases are capable of reducing also small molecules bearing an activated C=C double bond such as monocyclic enones and acyclic enoate esters. As preferred Δ4,5-steroid 5β-reductase (5β-StR) for this purpose, 5β-StR from Arabidopsis thaliana was used. In part, enzyme activities are even higher than that for progesterone. Successful preliminary biotransformations with enzymatic in situ cofactor recycling were also carried out. When using the prochiral compound isophorone as a substrate, a high enantioselective reaction course (>99% ee) was observed.
- Burda, Edyta,Krausser, Marina,Fischer, Gabriele,Hummel, Werner,Mueller-Uri, Frieder,Kreis, Wolfgang,Groeger, Harald
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experimental part
p. 2787 - 2790
(2010/03/05)
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- Heterogeneously catalyzed asymmetric hydrogenation of C=C bonds directed by surface-tethered chiral modifiers
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Asymmetric hydrogenation of C=C bonds is of the highest importance in organic synthesis, and such reactions are currently carried out with organometallic homogeneous catalysts. Achieving heterogeneous metal-catalyzed hydrogenation, a highly desirable goal
- Watson, David J.,Jesudason, R. J. Bennie Ram John,Beaumont, Simon K.,Kyriakou, Georgios,Burton, Jonathan W.,Lambert, Richard M.
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experimental part
p. 14584 - 14589
(2010/03/25)
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- TRANSHYDROGENATION PROCESSES
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This invention relates to a transhydrogenation process involving the dehydrogenating at least one cyclic compound that contains one or more saturated cyclic rings, and hydrogenating at least one cyclic or acyclic compound that contains at least one unsaturation and/or a functional group capable of undergoing hydrogenation. The process can be used to produce two or more commercially desirable products, including trimethylcyclohexanone.
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Page/Page column 7
(2009/08/14)
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- (BDP)CuH: A "hot" Stryker's reagent for use in achiral conjugate reductions
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(Chemical Equation Presented) A ligand-modified, economical version of Stryker's reagent (SR) has been developed based on a bidentate, achiral bis-phosphine. Generated in situ, "(BDP)CuH" smoothly effects conjugate reductions of a variety of unsaturated substrates, including those that are normally unreactive toward SR. Substrate-to-ligand ratios typically on the order of 1000-10000:1 can be used leading to products in high yields.
- Baker, Benjamin A.,Boskovic, Zarko V.,Lipshutz, Bruce H.
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p. 289 - 292
(2008/09/19)
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- Copper + nickel-in-charcoal (Cu-Ni/C): A bimetallic, heterogeneous catalyst for cross-couplings
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(Chemical Equation Presented) A new heterogeneous catalyst composed of copper and nickel oxide particles supported within charcoal has been developed. It catalyzes cross-couplings that traditionally use palladium, nickel, or copper, including Suzuki-Miyaura reactions, Buchwald-Hartwig aminations, vinylalane alkylations, etherifications of aryl halides, aryl halide reductions, asymmetric conjugate reductions of activated olefins, and azide-alkyne "click" reactions.
- Lipshutz, Bruce H.,Nihan, Danielle M.,Vinogradova, Ekaterina,Taft, Benjamin R.,Boskovic, Zarko V.
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supporting information; experimental part
p. 4279 - 4282
(2009/05/30)
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- Palladium catalyzed mild reduction of α,β-unsaturated compounds by triethylsilane
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The palladium(II) chloride/triethylsilane system has been successfully applied for the selective hydrogenation of the carbon-carbon double bond of α,β-unsaturated ketones to yield the corresponding saturated carbonyl compounds. The reaction takes place under mild conditions and affords high yields.
- Mirza-Aghayan, Maryam,Boukherroub, Rabah,Bolourtchian, Mohammad,Rahimifard, Mahshid
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p. 5113 - 5116
(2008/02/13)
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- Conjugate reduction of α,β-unsaturated carbonyl compounds promoted by nickel nanoparticles
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The system composed of nickel(II) chloride, lithium metal, a catalytic polymer-supported arene, and ethanol, has been efficiently applied to the conjugate reduction of a variety of α,β-unsaturated carbonyl compounds (ketones and carboxylic acid derivatives) under very mild reaction conditions. Georg Thieme Verlag Stuttgart.
- Alonso, Francisco,Osante, I?aki,Yus, Miguel
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p. 3017 - 3020
(2008/02/12)
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- A chemoselective hydrogenation of the olefinic bond of α,β- unsaturated carbonyl compounds in aqueous medium under microwave irradiation
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A microwave-assisted mild and ecofriendly catalytic transfer hydrogenation process was developed to reduce various α,β-unsaturated carbonyl compounds into the corresponding saturated carbonyl compounds in the presence of silica-supported palladium chloride as catalyst and a combination of MeOH/HCOOH/H2O (1:2:3) as hydrogen source within 22-55 minutes in moderate to excellent yields with 100% chemoselectivity.
- Sharma, Anuj,Kumar, Vinod,Sinha, Arun K.
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p. 354 - 360
(2007/10/03)
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- Hydrogenation of olefins using water and zinc metal catalyzed by a rhodium complex
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The hydrogenation of olefins using H2O or D2O as a hydrogen source and zinc metal as a reducing agent has been found to be catalyzed by a rhodium complex. α,β-Unsaturated ketones also underwent hydrogenation, affording the corresponding saturated ketones selectively.
- Sato, Takashi,Watanabe, Shoji,Kiuchi, Hiroyoshi,Oi, Shuichi,Inoue, Yoshio
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p. 7703 - 7705
(2007/10/03)
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- A metal nanoparticle-based supramolecular approach for aqueous biphasic reactions
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β-cyclodextrin immobilized on Pd nanoparticles was successfully employed as an efficient phase-transfer catalyst in aqueous biphasic hydrogenation reactions. The Royal Society of Chemistry 2005.
- Mhadgut, Shilpa C.,Palaniappan, Kumaranand,Thimmaiah, Muralidhara,Hackney, Stephen A.,Toeroek, Bela,Liu, Jian
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p. 3207 - 3209
(2007/10/03)
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- METHOD FOR PRODUCING 3, 3, 5-TRIMETHYLCYCLOHEXANONE
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PROBLEM TO BE SOLVED: To provide a new method for producing 3, 3, 5-trimethylcyclohexanone by the hydrogenation of isophorone in order to industrially advantageously produce 3, 3, 5-trimethylcyclohexanone. SOLUTION: The method for selectively producing 3, 3, 5-trimethylcyclohexanone comprises efficiently hydrogenating isophorone at a reaction temperature lower than the conventional method by using a palladium catalyst supported with activated carbon and/or a palladium catalyst supported with alumina in the method for producing 3, 3, 5-trimethylhexanone by the hydrogenation of isophorone by allowing carbon dioxide to participate in the reaction. The method is characterized by using the carbon dioxide having a temperature of 20-140°C and a pressure of 0.1-50 MPa and by using the hydrogen under conditions of a temperature of 20-140°C and a pressure of 0.1-30 MPa.
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Page/Page column 12-13
(2008/06/13)
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- METHOD FOR PRODUCING 3, 3, 5-TRIMETHYLCYCLOHEXANONE
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PROBLEM TO BE SOLVED: To provide a new method for producing 3, 3, 5-trimethylcyclohexanone by the hydrogenation of isophorone in order to industrially advantageously produce 3, 3, 5-trimethylcyclohexanone. SOLUTION: The method for producing 3, 3, 5-trimethylcyclohexanone comprises efficiently hydrogenating isophorone at a reaction temperature lower than the conventional method by using a rhodium and/or palladium supported catalyst in the method for producing 3, 3, 5-trimethylcyclohexanone by the hydrogenation of isophorone by allowing carbon dioxide to participate in the reaction. The method is characterized by using the carbon dioxide having a temperature of 20-250°C and a pressure of 0.1-50 MPa and by using the hydrogen under conditions of a temperature of 20-250°C and a pressure of 0.1-30 MPa.
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Page/Page column 11-12
(2008/06/13)
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- Iridium nanoparticles prepared in ionic liquids: An efficient catalytic system for the hydrogenation of ketones
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Ir(0) nanoparticles with 2.3 ± 0.4 nm in diameter prepared by simple reduction of [Ir(cod)Cl]2 in 1-n-butyl-3-methylimidazolium hexafluorophosphate ionic liquid constitute a simple, efficient and recyclable catalytic system for the solventless or biphasic hydrogenation of ketones under mild reaction conditions.
- Fonseca, Gledison S.,Scholten, Jackson D.,Dupont, Jairton
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p. 1525 - 1528
(2007/10/03)
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