- Hydrogenation reactions using scCO2 as a solvent in microchannel reactors
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We have developed an effective microfluidic system for hydrogenation reactions in ScCO2; the reactions proceeded very rapidly (within 1 second), by making the best use of ScCO2 and utilizing the large specific interfacial area of the microchannel reactor, and high reaction productivity was attained in each channel. The Royal Society of Chemistry 2005.
- Kobayashi, Juta,Mori, Yuichiro,Kobayashi, Shu
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- High-yielding tandem hydroformylation/hydrogenation of a terminal olefin to produce a linear alcohol using a Rh/Ru dual catalyst system
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(Chemical equation presented) A dual catalyst system has been developed for tandem hydroformylation/hydrogenation to produce n-undecanol from 1-decene in one pot. A combination of xantphos/[Rh(acac)(CO)2] and Shvo's catalyst (1) afforded the best results (see scheme; acac = acetylacetonate, DMA = N,N-dimethylacetamide). Polar solvents effectively suppressed the formation of undecyl formate.
- Takahashi, Kohei,Yamashita, Makoto,Ichihara, Takeo,Nakano, Koji,Nozaki, Kyoko
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- Impact of cyclodextrins on the behavior of amphiphilic ligands in aqueous organometallic catalysis
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In this study, we showed that the addition of randomly modified β-cyclodextrin (RAME-β-CD) in aqueous medium could have a beneficial impact on the catalytic performances of phosphane-based aggregates in the Pd-catalyzed cleavage of allyl carbonates (Tsuji-Trost reaction). The RAME-β-CD/phosphane supramolecular interactions helped explain the catalytic results. The presence of RAME-β-CD in the aqueous compartment improved the phosphane-based aggregate dynamics. The exchanges between the hydrophobic substrate-containing aggregate core and the catalyst-containing aqueous phase were then greatly favored, resulting in an increase in the catalytic performances.
- Bricout, Herve,Leonard, Estelle,Len, Christophe,Landy, David,Hapiot, Frederic,Monflier, Eric
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- Convenient synthesis of new amphiphilic triphenylphosphine analogues for aqueous biphasic catalysis
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The synthesis of three triphenylphosphine analogues with phenyl groups replaced by (4-tert-butyl)phenyl and (3-sulfonato)phenyl group is described. The surface-active properties of these new compounds are reported. The catalytic activities obtained with these phosphines in the palladium-catalyzed cleavage of undecyl allyl carbonate were up to 24000 times higher than those observed with trisulfonated triphenylphosphine, the ligand typically used in biphasic catalysis. One of these catalysts can be recovered six times without loss of catalytic activity.
- Caron, Laurent,Canipelle, Micha?l,Tilloy, Sébastien,Bricout, Hervé,Monflier, Eric
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- Ruthenium catalyzed hydrogenation of aldehyde with synthesis gas
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The hydrogenation of aldehyde utilizing synthesis gas as a dihydrogen source was examined with various ruthenium catalysts, among which Ru-cyclopentadienone complexes (Shvo-type catalysts) exhibited higher activity than others. DFT calculations proved that the exchange of coordinated carbon monoxide by dihydrogen is relatively preferable in Shvo-type catalysts compared to others, which is a pre-equilibrium for the generation of the hydrogenation-active species.
- Takahashi, Kohei,Nozaki, Kyoko
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- Ditopic cyclodextrin-based receptors: New perspectives in aqueous organometallic catalysis
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The mass transfer properties of mono- and ditopic β-cyclodextrin-based receptors have been evaluated in a biphasic palladium-catalyzed Tsuji-Trost reaction and compared to one of the best mass-transfer promoters, namely the randomly methylated β-cyclodextrin. While monotopic receptors appeared to be poor mass-transfer promoters of long alkyl chain allyl carbonates or urethanes, cooperative effects have been evidenced with ditopic cyclodextrin-based receptors, opening new perspectives in aqueous organometallic catalysis.
- Six, Natacha,Menuel, Stephane,Bricout, Herve,Hapiot, Frederic,Monflier, Eric
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- Amphiphilic photo-isomerisable phosphanes for aqueous organometallic catalysis
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Water-soluble phosphanes were tagged with a light-responding diazo group. Upon UV exposure, the diazo-isomerisation led to phosphane morphology change, resulting in an increase in the reaction rate of an aqueous palladium-catalysed cleavage reaction. The Royal Society of Chemistry.
- Bricout, Herve,Banaszak, Estelle,Len, Christophe,Hapiot, Frederic,Monflier, Eric
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- Scope and limitation of activated carbons in aqueous organometallic catalysis
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The effect of activated carbons has been studied in the palladium-catalyzed cleavage reaction of allylalkylcarbonate under aqueous biphasic conditions. A number of parameters were investigated, such as the type of carbon, the structure of the water-soluble ligand, the water conditions, and the metal complex loading. It was found that the intrinsic properties of carbons had a strong influence on the reaction rates. The best performances were obtained with the AC-WV carbon possessing the largest part of mesopores and lowest content of oxygen-surface groups. The results were rationalized by considering that AC-WV acted as a mass-transfer promoter increasing the interfacial area and collisions between the reactive species in the pore volume. The hypothesis of a confinement effect of the catalyst and reactants within the pores via adsorption-desorption processes was supported by isothermal studies and 31P{1H} NMR investigations.
- Kania, Nicolas,Gokulakrishnan, Narasimhan,Leger, Bastien,Fourmentin, Sophie,Monflier, Eric,Ponchel, Anne
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- Chemically modified β-cyclodextrins: Efficient supramolecular carriers for the biphasic hydrogenation of water-insoluble aldehydes
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Hydrogenation of water-insoluble aldehydes can be achieved in high yields in a genuine two-phase system by using a recoverable catalytic system composed of a water-soluble ruthenium/triphenylphosphine trisulfonate complex and a suitable chemically modified β-cyclodextrin.
- Monflier, Eric,Tilloy, Sebastien,Castanet, Yves,Mortreux, Andre
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- Molecular recognition between a water-soluble organometallic complex and a β-cyclodextrin: First example of second-sphere coordination adducts possessing a catalytic activity
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Formation of stable second-sphere adducts between a water-soluble organometallic complex and a cyclodextrin (CD) is possible by finely designing the structure of the water-soluble phosphane. The key point to obtain such adducts was the synthesis of a water-soluble phosphane which possesses a tert-butylphenyl group recognized by the CD and separated from the phosphorus atom by a phenyl ring to avoid phosphane decoordination during the molecular recognition process between the organometallic complex and the CD. These adducts are able to catalyze the cleavage of water-insoluble carbonate in a biphasic system.
- Caron, Laurent,Bricout, Herve,Tilloy, Sebastien,Ponchel, Anne,Landy, David,Fourmentin, Sophie,Monflier, Eric
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- Scope and limitations of biocatalytic carbonyl reduction with white-rot fungi
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The reductive activity of various basidiomycetous fungi towards carbonyl compounds was screened on an analytical level. Some strains displayed high reductive activities toward aromatic carbonyls and aliphatic ketones. Utilizing growing whole-cell cultures of Dichomitus albidofuscus, the reactions were up-scaled to a preparative level in an aqueous system. The reactions showed excellent selectivities and gave the respective alcohols in high yields. Carboxylic acids were also reduced to aldehydes and alcohols under the same conditions. In particular, benzoic, vanillic, ferulic, and p-coumaric acid were reduced to benzyl alcohol, vanillin, dihydroconiferyl alcohol and 1-hydroxy-3-(4-hydroxyphenyl)propan, respectively.
- Zhuk, Tatyana S.,Skorobohatko, Oleksandra S.,Albuquerque, Wendell,Zorn, Holger
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supporting information
(2021/02/02)
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- Selective hydroboration of equilibrating allylic azides
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The iridium(i)-catalyzed hydroboration of equilibrating allylic azides is reported to provide only the anti-Markovnikov product of alk-1-ene isomers in good yields and with good functional group tolerance.
- Liu, Ruzhang,Xu, Jun,Zhang, Yuanyuan
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supporting information
p. 8913 - 8916
(2021/09/13)
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- Selective Production of Linear Aldehydes and Alcohols from Alkenes using Formic Acid as Syngas Surrogate
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Performing carbonylation without the use of carbon monoxide for high-value-added products is an attractive yet challenging topic in sustainable chemistry. Herein, effective methods for producing linear aldehydes or alcohols selectively with formic acid as both carbon monoxide and hydrogen source have been described. Linear-selective hydroformylation of alkenes proceeds smoothly with up to 88 % yield and >30 regioselectivity in the presence of single Rh catalyst. Strikingly, introducing Ru into the system, the dual Rh/Ru catalysts accomplish efficient and regioselective hydroxymethylation in one pot. The present processes utilizing formic acid as syngas surrogate operate simply under mild condition, which opens a sustainable way for production of linear aldehydes and alcohols without the need for gas cylinders and autoclaves. As formic acid can be readily produced via CO2 hydrogenation, the protocols represent indirect approaches for chemical valorization of CO2.
- Chen, Junjun,Hua, Kaimin,Liu, Xiaofang,Deng, Yuchao,Wei, Baiyin,Wang, Hui,Sun, Yuhan
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p. 9919 - 9924
(2021/05/31)
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- Multicatalytic approach to one-pot stereoselective synthesis of secondary benzylic alcohols
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One-pot procedures bear the potential to rapidly build up molecular complexity without isolation and purification of consecutive intermediates. Here, we report multicatalytic protocols that convert alkenes, unsaturated aliphatic alcohols, and aryl boronic acids into secondary benzylic alcohols with high stereoselectivities (typically >95:5 er) under sequential catalysis that integrates alkene cross-metathesis, isomerization, and nucleophilic addition. Prochiral allylic alcohols can be converted to any stereoisomer of the product with high stereoselectivity (>98:2 er, >20:1 dr).
- Casnati, Alessandra,Lichosyt, Dawid,Lainer, Bruno,Veth, Lukas,Dydio, Pawe?
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supporting information
p. 3502 - 3506
(2021/05/10)
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- Fe-Catalyzed Anaerobic Mukaiyama-Type Hydration of Alkenes using Nitroarenes
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Hydration of alkenes using first row transition metals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama-type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe-catalyzed anaerobic Markovnikov-selective hydration of alkenes using nitroarenes as oxygenation reagents is reported. The nitro moiety is not well explored in radical chemistry and nitroarenes are known to suppress free radical processes. Our findings show the potential of cheap nitroarenes as oxygen donors in radical transformations. Secondary and tertiary alcohols were prepared with excellent Markovnikov-selectivity. The method features large functional group tolerance and is also applicable for late-stage chemical functionalization. The anaerobic protocol outperforms existing hydration methodology in terms of reaction efficiency and selectivity.
- Bhunia, Anup,Bergander, Klaus,Daniliuc, Constantin Gabriel,Studer, Armido
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supporting information
p. 8313 - 8320
(2021/03/08)
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- Ruthenium-catalyzed hydrogenation of CO2as a route to methyl esters for use as biofuels or fine chemicals
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A novel robust diphosphine-ruthenium(ii) complex has been developed that can efficiently catalyze both the hydrogenation of CO2 to methanol and its in situ condensation with carboxylic acids to form methyl esters; a TON of up to 3260 is achievable for the CO2 to methanol step. Both aromatic and aliphatic carboxylic acids can be transformed to their corresponding methyl esters with high conversion and selectivity (17 aliphatic and 18 aromatic examples). On the basis of a series of experiments, a mechanism has been proposed to account for the various steps involved in the catalytic pathway. More importantly, this approach provides a promising route for using CO2 as a C1 source for the production of biofuels, fine chemicals and methanol.
- Li, Yong,Liu, Qingbin,Ma, Yanping,Solan, Gregory A.,Sun, Wen-Hua,Wang, Zheng,Zhang, Qiuyue,Zhao, Ziwei,Zhong, Yanxia
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p. 6766 - 6774
(2020/08/25)
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- Ir-catalyzed tandem hydroformylation-transfer hydrogenation of olefins with (trans-/cis-)formic acid as hydrogen source in presence of 1,10-phenanthroline
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The one-pot tandem hydroformylation-reduction to synthesize alcohols from olefins is in great demand but suffering from low yields, poor selectivity and harsh condition. Herein, 1,10-phenanthroline (L1) modified Ir-catalyst proved to exhibit multiple cata
- Chen, Xiao-Chao,Gao, Han,Liu, Lei,Liu, Ye,Lu, Yong,Xia, Fei,Yang, Shu-Qing
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p. 183 - 193
(2020/04/08)
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- New strategy for production of primary alcohols from aliphatic olefins by tandem cross-metathesis/hydrogenation
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Primary alcohols are widely used in industry as solvents and precursors of detergents. The classic methods for hydration of terminal alkenes always produce the Markovnikov products. Herein, we reported a reliable approach to produce primary alcohols from terminal alkenes combining with biomass-derived allyl alcohol by tandem cross-metathesis/hydrogenation. A series of primary alcohol with different chain lengths was successfully produced in high yields (ca. 90percent). Computational studies revealed that self-metathesis and hydrogenation of substrates are accessible but much slower than cross-metathesis. This new methodology represents a unique alternative to primary alcohols from terminal alkenes.
- Jia, Ruilong,Zuo, Zhijun,Li, Xu,Liu, Lei,Dong, Jinxiang
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supporting information
p. 1525 - 1529
(2019/11/11)
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- Iron-catalyzed protodehalogenation of alkyl and aryl halides using hydrosilanes
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A simple and efficient iron-catalyzed protodehalogenation of alkyl and aryl halides using phenylhydrosilane is disclosed. The reaction utilizes FeCl3 without the requirement of ligands. Unactivated alkyl and aryl halides were successfully reduced in good yields; sterically hindered tertiary halides were also reduced including the less reactive chlorides. The scalability of this methodology was demonstrated by a gram-scale synthesis with a catalyst loading as low as 0.5 mol%. Notably, disproportionation of phenylsilane leads to diphenylsilane that further reduces the halides. Preliminary mechanistic studies revealed a non-radical pathway and the source of hydrogen is PhSiH3via deuterium labeling studies. Our methodology represents simplicity and provides a good alternative to typical tin, aluminum and boron hydride reagents.
- Pilli, Ramadevi,Balakrishnan, Venkadesh,Chandrasekaran, Revathi,Rasappan, Ramesh
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supporting information
p. 1749 - 1753
(2019/02/20)
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- Tris(pyrazolyl)borate Cobalt-Catalyzed Hydrogenation of C=O, C=C, and C=N Bonds: An Assistant Role of a Lewis Base
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The combination of tris(pyrazolyl)borate cobalt complexes and Lewis base is developed as an efficient catalyst precursor in the homogeneous hydrogenation. A broad substrate scope including carbonyls, alkenes, enamines, and imines is reduced with 60 atm of H2 at 60 °C. Mechanistic studies support the hydrogenation operates through a frustrated Lewis pair (FLP)-like reduction process. These results highlight the development of novel non-noble metal catalytic processes, when combined with the diverse small molecule activation chemistry associated with FLPs.
- Lin, Yang,Zhu, De-Ping,Du, Yi-Ran,Zhang, Rui,Zhang, Suo-Jiang,Xu, Bao-Hua
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supporting information
p. 2693 - 2698
(2019/04/25)
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- Discovery and Comparison of Homogeneous Catalysts in a Standardized HOT-CAT Screen with Microwave-Heating and qNMR Analysis: Exploring Catalytic Hydration of Alkynes
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A HOT-CAT (homogeneous thermal catalysis) screen using microwave-heating and quantitative NMR (qNMR) analysis has been developed for identification and comparison of catalyst activity in homogeneous metal-based catalysis. The hydration of terminal alkynes to ketones or aldehydes served as a model reaction in this proof-of-concept study. Key aspects of the screen are the use of a high-temperature setting (e. g., 160 °C) at a fixed, short reaction time (e. g., 15 min) for all samples. Analysis of crude reaction mixtures by a standardized, quantitative 1H NMR protocol gives a comprehensive picture of catalyst chemo- and regioselectivity, which permits broad comparisons and the discovery of non-target reactivity. For catalytic alkyne hydration, data for 105 runs involving 81 catalyst systems with 15 different metals is presented. The activity of all established catalyst systems was reproduced, and new catalyst systems with Markovnikov hydration selectivity were discovered and applied to preparative runs, namely Cu2O?CSA (CSA=camphorsulfonic acid), Co(OAc)2?tetraphenylporphyrin?CSA and [IrCl(COD)]?CSA.
- Brunner, Andreas,Hintermann, Lukas,Milzarek, Tobias M.,Schreyer, Matthias,Wegmann, Marcus
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- Hydrofunctionalization of Olefins to Higher Aliphatic Alcohols via Visible-Light Photocatalytic Coupling
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Abstract: An atomically economical green protocol for the hydrofunctionalization of olefins to higher aliphatic alcohols with 100% anti-Markovnikov regioselectivity was developed via visible-light photocatalytic coupling. This method employs cheap, readily available and abundant methanol as both the C1 feedstock and the hydrogen source under visible light irradiation over CdS photocatalyst. A wide scope of olefin substrates could be hydrofunctionalized successfully to the corresponding higher alcohols with high selectivity. Besides alcohol, acetone and acetonitrile can also couple with olefins to generate the corresponding hydrofunctionalization products, suggesting promising potential industrial application. Graphical Abstract: [Figure not available: see fulltext.] Hydrofunctionalization of olefins to value-added chemicals with high selectivity was achieved via visible-light photocatalytic cross-coupling.
- Bao, Jingxian,Fan, Yonghui,Zhang, Shuyi,Zhong, Liangshu,Wu, Minghong,Sun, Yuhan
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- Diaminodiphosphine tetradentate ligand and ruthenium complex thereof, and preparation methods and applications of ligand and complex
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The invention discloses a diaminodiphosphine tetradentate ligand and a ruthenium complex thereof, and preparation methods and applications of the ligand and the complex, and provides a ruthenium complex represented by a formula I, wherein L is a diaminodiphosphine tetradentate ligand represented by a formula II, and X and Y are respectively and independently chlorine ion, bromine ion, iodine ion,hydrogen negative ion or BH4. According to the present invention, the ruthenium complex exhibits excellent catalytic activity in the catalytic hydrogenation reactions of ester compounds, has high yield and high chemical selectivity, is compatible with conjugated and non-conjugated carbon-carbon double bond, carbon-carbon triple bond, epoxy, halogen, carbonyl and other functional groups, and hasgreat application prospects.
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Paragraph 0307-0309; 0311
(2019/11/04)
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- Selective ligand-free cobalt-catalysed reduction of esters to aldehydes or alcohols
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Cobalt(ii) salts combined with NaBHEt3 and eventually a base catalyse efficiently and selectively the reduction of esters to aldehydes or alcohols through hydrosilylation by using phenylsilane. Catalyst characterisation by XRD, XPS, TEM and STEM analyses indicates the materials were partially crystalline with the presence of cobalt nanoparticles. Control experiments suggested low valent Co(0) was the active catalytic species involved.
- Rysak, Vincent,Descamps-Mandine, Armel,Simon, Pardis,Blanchard, Florent,Burylo, Laurence,Trentesaux, Martine,Vandewalle, Maxence,Collière, Vincent,Agbossou-Niedercorn, Francine,Michon, Christophe
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p. 3504 - 3512
(2018/07/29)
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- Transfer Hydrogenation of Alkenes Using Ethanol Catalyzed by a NCP Pincer Iridium Complex: Scope and Mechanism
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The first general catalytic approach to effecting transfer hydrogenation (TH) of unactivated alkenes using ethanol as the hydrogen source is described. A new NCP-type pincer iridium complex (BQ-NCOP)IrHCl containing a rigid benzoquinoline backbone has been developed for efficient, mild TH of unactivated C-C multiple bonds with ethanol, forming ethyl acetate as the sole byproduct. A wide variety of alkenes, including multisubstituted alkyl alkenes, aryl alkenes, and heteroatom-substituted alkenes, as well as O- or N-containing heteroarenes and internal alkynes, are suitable substrates. Importantly, the (BQ-NCOP)Ir/EtOH system exhibits high chemoselectivity for alkene hydrogenation in the presence of reactive functional groups, such as ketones and carboxylic acids. Furthermore, the reaction with C2D5OD provides a convenient route to deuterium-labeled compounds. Detailed kinetic and mechanistic studies have revealed that monosubstituted alkenes (e.g., 1-octene, styrene) and multisubstituted alkenes (e.g., cyclooctene (COE)) exhibit fundamental mechanistic difference. The OH group of ethanol displays a normal kinetic isotope effect (KIE) in the reaction of styrene, but a substantial inverse KIE in the case of COE. The catalysis of styrene or 1-octene with relatively strong binding affinity to the Ir(I) center has (BQ-NCOP)IrI(alkene) adduct as an off-cycle catalyst resting state, and the rate law shows a positive order in EtOH, inverse first-order in styrene, and first-order in the catalyst. In contrast, the catalysis of COE has an off-cycle catalyst resting state of (BQ-NCOP)IrIII(H)[O(Et)···HO(Et)···HOEt] that features a six-membered iridacycle consisting of two hydrogen-bonds between one EtO ligand and two EtOH molecules, one of which is coordinated to the Ir(III) center. The rate law shows a negative order in EtOH, zeroth-order in COE, and first-order in the catalyst. The observed inverse KIE corresponds to an inverse equilibrium isotope effect for the pre-equilibrium formation of (BQ-NCOP)IrIII(H)(OEt) from the catalyst resting state via ethanol dissociation. Regardless of the substrate, ethanol dehydrogenation is the slow segment of the catalytic cycle, while alkene hydrogenation occurs readily following the rate-determining step, that is, β-hydride elimination of (BQ-NCOP)Ir(H)(OEt) to form (BQ-NCOP)Ir(H)2 and acetaldehyde. The latter is effectively converted to innocent ethyl acetate under the catalytic conditions, thus avoiding the catalyst poisoning via iridium-mediated decarbonylation of acetaldehyde.
- Wang, Yulei,Huang, Zhidao,Leng, Xuebing,Zhu, Huping,Liu, Guixia,Huang, Zheng
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supporting information
p. 4417 - 4429
(2018/04/05)
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- Inexpensive and rapid hydrogenation catalyst from CuSO4/CoCl2 — Chemoselective reduction of alkenes and alkynes in the presence of benzyl protecting groups
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The simple reduction of a number of alkenes and alkynes was performed with a typical reaction time of 20 min using a copper-cobalt catalytic system. The reduction did not cleave benzyl protecting groups which are usually vulnerable to catalytic hydrogenation reactions. The catalyst can be prepared in situ by reduction of the inexpensive precursor salts CuSO4 and CoCl2 with NaBH4. Sodium borohydride was also used as an easily handled hydrogen source for the catalytic reductions. No pressure, heating or inert atmosphere is required and purification/catalyst removal is achieved using extraction procedures, making this approach simple and efficient.
- Ficker, Mario,Svenningsen, S?ren W.,Larribeau, Thomas,Christensen, J?rn B.
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supporting information
p. 1125 - 1129
(2018/02/21)
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- Hydrofunctionalization of olefins to value-added chemicals: Via photocatalytic coupling
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A green strategy was developed for the synthesis of various value-added chemicals using methanol, acetonitrile, acetic acid, acetone and ethyl acetate as the hydrogen source by coupling them with olefins over heterogeneous photocatalysts. A radical coupling mechanism was proposed for the hydrofunctionalization of olefins with methanol to higher aliphatic alcohols over the Pt/TiO2 catalyst as the model reaction. C-H bond cleavage and C-C bond formation between photogenerated radicals and terminal olefins were accomplished in a single reaction at high efficiency. Our approach is atomically economical with high anti-Markovnikov regioselectivity and promising application potential under mild reaction conditions.
- Fan, Yonghui,Li, Shenggang,Bao, Jingxian,Shi, Lei,Yang, Yanzhang,Yu, Fei,Gao, Peng,Wang, Hui,Zhong, Liangshu,Sun, Yuhan
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supporting information
p. 3450 - 3456
(2018/08/06)
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- Scalable thin-layer membrane reactor for heterogeneous and homogeneous catalytic gas-liquid reactions
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Catalytic gas-liquid reactions have potential as environmentally benign methods for organic synthesis, particularly hydrogenation and oxidation reactions. However, safety and scalability are concerns in the application of gas-liquid reactions. In this work, we develop and demonstrate a scalable, sustainable, and safe thin-layer membrane reactor for heterogeneous Pd-catalyzed hydrogenations and homogenous Cu(i)/TEMPO alcohol oxidations. The implementation of a Teflon amorphous fluoroplastic (AF) membrane and porous carbon cloth in the membrane reactor provides sufficient gas-liquid mass transfer to afford superior performance compared to conventional packed-bed or trickle-bed reactors. The membrane separates the gas from the liquid, which avoids the formation of explosive mixtures for oxygenation reactions and simplifies the two-phase hydrodynamics to facilitate scale-up by stacking modules, while significantly reducing gas consumption. In addition, 3-dimensional simulations deliver insights into the mass transfer and hydrodynamic behavior to inform optimal membrane reactor design and operation.
- Mo, Yiming,Imbrogno, Joseph,Zhang, Haomiao,Jensen, Klavs F.
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p. 3867 - 3874
(2018/08/21)
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- A Versatile Iridium(III) Metallacycle Catalyst for the Effective Hydrosilylation of Carbonyl and Carboxylic Acid Derivatives
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A versatile iridium(III) metallacycle catalysed rapidly and selectively the reduction of a large array of challenging esters and carboxylic acids as well as various ketones and aldehydes. The reactions proceeded in high yields at room temperature by hydrosilylation followed by desilylation. Although the reactions of various aldehydes and ketones resulted exclusively in alcohols, the hydrosilylation of esters led to alcohols or ethers, depending on the type of substrate. Regarding the carboxylic acids, again the nature of the reagent controlled the outcome of the hydrosilylation reaction, either alcohols or aldehydes being formed.
- Corre, Yann,Rysak, Vincent,Trivelli, Xavier,Agbossou-Niedercorn, Francine,Michon, Christophe
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supporting information
p. 4820 - 4826
(2017/09/07)
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- Hydroformylation-hydrogenation and hydroformylation-acetalization reactions catalyzed by ruthenium complexes
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In this work, the catalytic activity of ruthenium II and III complexes containing chloride, pyridine, phosphine and CO ligands was investigated in the hydroformylation – hydrogenation and hydroformylation – acetalization reactions. The complexes mer-[RuCl3(dppb)(H2O)](1), mer-[RuCl3(dppb)(4-Vpy)](2), mer-[RuCl3(dppb)(4-tBupy)](3), mer-[RuCl3(dppb)(py)](4), mer-[RuCl3(dppb)(4-Phpy)](5), mer-[RuCl3(dppb)(4-Mepy)](6), cis-[RuCl2(CO)2(dppb)](7), trans-[RuCl2(CO)2(dppb)](8), RuCl3·xH2O(9), [RuCl2(PPh3)3](10) and [RuCl2(PPh3)2(dppb)](11) were used as supplied or synthesized as previously described in the literature {Where PPh3?=?triphenylphosphine, dppb?=?1,4-bis(diphenylphosphino)butane, py?=?pyridine, 4-Mepy?=?4-methylpyridine, 4-Vpy?=?4-vinylpyridine, 4-tBupy?=?4-tert-butylpyridine and 4-Phpy?=?4-phenylpyridine}. These complexes were used as a pre-catalysts in a hydroformylation catalytic system to produce C[sbnd]C, C[dbnd]O and C[sbnd]O bonds, where 1-decene resulted in a formation of respective alcohol and dimethyl acetals. Several reactions were performed in order to find the best reaction conditions presenting the best conversion (64% after 24?h). The 1-decene was also used as a substrate in two type tandem reactions labeled as: hydroformylation – hydrogenation (HH) and hydroformylation – acetalization (HA) reactions. The relationship between Ru – catalyst/substrate was 1:100, without free ligands or additives, in a controlled temperature and pressure. All the products of catalytic reactions HH and HA were analyzed by CG-FID with good yields.
- Rodrigues, Claudia,Delolo, Fabio G.,Norinder, Jakob,B?rner, Armin,Bogado, André L.,Batista, Alzir A.
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p. 586 - 592
(2016/12/16)
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- Ruthenium(III)/phosphine/pyridine complexes applied in the hydrogenation reactions of polar and apolar double bonds
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In this work, five ruthenium(III) complexes containing phosphine and pyridine based ligands with general formula mer-[RuCl3(dppb)(N)] [where dppb = 1,4-bis(diphenylphosphino)butane and N = pyridine (py), 4-methylpyridine (4-Mepy), 4-vinylpyridine (4-Vpy), 4-tert-butylpyridine (4-tBupy) and 4-phenylpyridine (4-Phpy)] were synthesized and characterized using spectroscopic and electrochemical techniques, as well as magnetic susceptibility to check the paramagnetism of these compounds. These complexes were tested as catalytic precursors in hydrogenation reactions with cyclohexene, undecanal and cyclohexanecarboxaldehyde, as compounds bearing C=C and C=O groups. Broad screening was carried out in order to find the optimal reaction conditions with the highest conversion. It was found that by using a ratio of Ru-catalyst/substrate = 1:530 at 80°C and 15 bar of H2 for 24 h, cyclohexene can be reduced. Hydrogenation of undecanal was possible using a Ru-catalyst/substrate ratio of 1:100 at 160°C and 100 bar for 24 h, and for the reduction of cyclohexanecarboxaldehyde the reaction conditions were Ru-catalyst/substrate ratio of 1:100 at 160°C and 50 bar for 24 h.
- Rodrigues, Claudia,Delolo, Fábio G.,Ferreira, Lucas M.,Da S Maia, Pedro I.,Deflon, Victor M.,Rabeah, Jabor,Brückner, Angelika,Norinder, Jakob,B?rner, Armin,Bogado, André L.,Batista, Alzir A.
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- A method of manufacturing a terminal alcohol
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PROBLEM TO BE SOLVED: To produce in high yield a terminal alcohol having high straight-chain selectivity by a single-step reaction comprising: reacting an internally olefinic compound with hydrogen and carbon monoxide in the presence of a catalyst.SOLUTION: A method for producing a terminal alcohol includes a process in which an internally olefinic compound is reacted with hydrogen and carbon monoxide using a polar solvent in the presence of a catalyst comprising: a rhodium compound, a bidentate organic phosphorus compound and a compound containing one or more group 8-10 transition metals except rhodium. A hydroformylation catalyst comprising a rhodium-bidentate organic phosphorus-based compound expressing high straight-chain selectivity is coexisted with group 8-10 transition metal(s) except rhodium as a catalyst for selective hydrogenation of an aldehyde formed in the reaction system and the reaction is carried out using a polar solvent. Thus, the objective terminal alcohol significantly improved in straight-chain selectivity is efficiently produced in a single-step reaction.
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Paragraph 0123-0126
(2017/06/02)
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- From alkenes to alcohols by cobalt-catalyzed hydroformylation-reduction
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The cobalt-catalyzed hydroformylation of alkenes in the presence of a range of novel cyclic phosphine ligands was investigated. The effect of various parameters such as solvents, additives, cobalt/phosphine ratio, CO/H2 (1:2), and nature of the alkenes was examined. The results revealed that both terminal and internal alkenes are hydroformylated in high yields to give mainly linear products at moderate temperature and syn gas pressure. The linearity ranges from 43 to 85%, with Lim-10 giving the highest proportion of linear product.
- Achonduh, George,Yang, Qian,Alper, Howard
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supporting information
p. 1241 - 1246
(2015/03/05)
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- Being two is better than one - Catalytic reductions with dendrimer encapsulated copper - And copper-cobalt-subnanoparticles
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Copper and copper-cobalt subnanoparticles have been synthesized using 4-carbomethoxypyrrolidone terminated PAMAM-dendrimers as templates. The metal particles were applied in catalytic reduction reactions. While Cu subnanoparticles were only capable of reducing conjugated double bonds, enhancing the Cu particles with Co led to a surprising increase in catalytic activity, reducing also isolated carbon double and triple bonds.
- Ficker, Mario,Petersen, Johannes F.,Gschneidtner, Tina,Rasmussen, Ann-Louise,Purdy, Trevor,Hansen, Jon S.,Hansen, Thomas H.,Husted, S?ren,Moth Poulsen, Kasper,Olsson, Eva,Christensen, J?rn B.
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supporting information
p. 9957 - 9960
(2015/06/22)
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- PROCESS FOR THE CHEMOSELECTIVE REDUCTION OF TERMINALLY SATURATED CARBOXYLIC ESTERS
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The chemoselective reduction of a carboxylic ester (I) to an alcohol by catalytic hydrogenation, in particular in the presence of a transition metal complex, more particularly in the presence of a ruthenium (II) complex is described.
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Paragraph 0066; 0067
(2015/06/10)
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- Pd-catalyzed reduction of aldehydes to alcohols using formic acid as the hydrogen donor
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Facile and selective reduction of aromatic aldehydes as well as aliphatic aldehydes to alcohols was achieved using formic acid as the hydrogen donor in the presence of a catalytic amount of Pd(OAc)2 and Cy3P. It was found that both hydrogen atoms in the formic acid molecule can serve as the hydride source. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications for the following free supplemental resource(s): Full experimental and spectral details.]
- Wang, Anwei,Yang, Zhiyong,Liu, Jidan,Gui, Qingwen,Chen, Xiang,Tan, Ze,Shi, Ji-Cheng
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supporting information
p. 280 - 288
(2013/12/04)
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- Lutidine-derived Ru-CNC hydrogenation pincer catalysts with versatile coordination properties
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Lutidine-derived bis-N-heterocyclic carbene (NHC) ruthenium CNC-pincer complexes (Ru-CNC's) were prepared. Depending on the synthetic procedure, normal (1, 2) or mixed normal/abnormal NHC-complexes (3) are formed. In the presence of phosphazene base, Ru-CNC complexes activate nitriles to give ketimino compounds 4-6. Nitrile adduct 4 shows reactivity toward strong bases to yield dearomatized complex 7, which heterolytically activates H2 to form the bis-hydrido complex 8. Finally, these Ru-CNC's are active in catalytic hydrogenation of CO2 to formate salts, and unlike the phosphine-containing Ru-PNP counterpart, they also catalyze the selective hydrogenation of esters to alcohols.
- Filonenko, Georgy A.,Cosimi, Elena,Lefort, Laurent,Conley, Matthew P.,Copéret, Christophe,Lutz, Martin,Hensen, Emiel J.M.,Pidko, Evgeny A.
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p. 2667 - 2671
(2014/08/18)
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- COMPLEX CATALYSTS BASED ON AMINO-PHOSPHINE LIGANDS FOR HYDROGENATION AND DEHYDROGENATION PROCESSES
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The present application discloses novel PWNN and PWNWP metal catalysts for organic chemical syntheses including hydrogenation (reduction) of unsaturated compounds or dehydrogenation of substrates. The range of hydrogenation substrate compounds includes esters, lactones, enals, enones, enolates, oils and fats, resulting in alcohols, enols, diols, and triols as reaction products. The catalysts of current application can be used to catalyze a hydrogenation reaction under solvent free conditions. The present catalysts also allow the hydrogenation to proceed without added base, and it can be used in place of the conventional reduction methods employing hydrides of the main-group elements. Furthermore, the catalysts of the present application can catalyze a dehydrogenation reaction under homogenous and/or acceptorless conditions. As such, the catalysts provided herein can be useful in substantially reducing cost and improving the environmental profile of manufacturing processes for a variety of chemicals.
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Page/Page column 38; 39
(2014/09/29)
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- Efficient hydroxymethylation reactions of iodoarenes using CO and 1,3-dimethylimidazol-2-ylidene borane
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A hydroxymethylation reaction of a variety of iodoarenes proceeded effectively in the presence of CO, NHC-borane, diMeImd-BH3 (2) as a radical mediator, and a catalytic amount of AIBN. The reaction took place chemoselectively at the aryl-iodine bond but not at the aryl-bromine and aryl-chlorine bonds. A three-component coupling reaction comprising aryl iodides, CO, and electron-deficient alkenes also proceeded well to give unsymmetrical ketones in good yields. Control experiments show that 2 would act as a hydrogen donor to acyl radicals and iodinated NHC-borane as a reducing agent of aldehydes.
- Kawamoto, Takuji,Okada, Takuma,Curran, Dennis P.,Ryu, Ilhyong
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supporting information
p. 2144 - 2147
(2013/06/05)
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- Selective reduction of dienes/polyenes using sodium borohydride/catalytic ruthenium(III) in various liquid amide aqueous mixtures
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An efficient method to effect selective reduction of several structurally diverse dienes and an unsymmetrical triene is reported. The reduction is facile at 0 °C in a liquid amide aqueous solution containing sodium borohydride in the presence of 15 mol % ruthenium(III) chloride. The chemoselectivity of the reaction is controlled by proper choice of the liquid amide solvent.
- Babler, James H.,Ziemke, David W.,Hamer, Robert M.
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p. 1754 - 1757
(2013/04/10)
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- Tandem isomerization/hydroformylation/hydrogenation of internal alkenes to n-alcohols using Rh/Ru dual-or ternary-catalyst systems
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A one-pot three-step reaction, isomerization/hydroformylation/hydrogenation of internal alkenes to n-alcohols, was accomplished by employing a Rh/Ru dual-catalyst system. By using a combination of Rh(acac)(CO)2/ bisphosphite and Shvo's catalyst, (Z)-2-tridecene was converted to 1-tetradecanol in 83% yield with high normal/iso selectivity (n/i = 12). The method was applicable to other internal alkenes, including functionalized alkenes, such as an alkenol and an alkenoate. Furthermore, addition of a third component, Ru3(CO)12, effectively improved the n/i ratio in the tandem isomerization/hydroformylation/hydrogenation of methyl oleate (from n/i = 1.9 to 4.4). Control experiments revealed that the isomerization was mediated by both Rh and Ru and that the coexistence of Rh and Ru was essential for hydrogenation of aldehyde under H2/CO.
- Yuki, Yamato,Takahashi, Kohei,Tanaka, Yoshiyuki,Nozaki, Kyoko
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p. 17393 - 17400
(2014/01/06)
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- Homogeneous catalysis, heterogeneous recycling: A new family of branched molecules with hydrocarbon or fluorocarbon chains for the Friedl?nder synthesis of quinoline under solvent-free conditions
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A new family of branched catalysts with hydrocarbon or fluorocarbon chains was used to catalyze Friedl?nder reaction between 2-aminoarylketones and α-methylene ketones under solvent-free conditions in good to excellent yields. The catalysts exhibit temperature-dependent solubility and such a thermomorphic character allows them to be recovered by filtration conveniently at room temperature and reused at least five times. To some extent, the branched catalysts with hydrocarbon chains are superior to those with fluorocarbon chains, as they are cheaper and more biodegradable.
- Fang, Lei,Yu, Jianjun,Liu, Ying,Wang, Anyin,Wang, Limin
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p. 11004 - 11009
(2014/01/06)
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- From olefins to alcohols: Efficient and regioselective ruthenium-catalyzed domino hydroformylation/reduction sequence
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Exploring the alternatives: Ruthenium imidazoyl phosphine complexes catalyze the domino hydroformylation/reduction of alkenes to alcohols in good yields and with good selectivities (see scheme). Linear aliphatic alcohols are synthesized under reaction conditions typically used in industrial hydroformylations. Copyright
- Fleischer, Ivana,Dyballa, Katrin Marie,Jennerjahn, Reiko,Jackstell, Ralf,Franke, Robert,Spannenberg, Anke,Beller, Matthias
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supporting information
p. 2949 - 2953
(2013/04/10)
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- PROCESS FOR THE CHEMOSELECTIVE REDUCTION OF TERMINALLY SATURATED CARBOXYLIC ESTERS
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The chemoselective reduction of a carboxylic ester (I) to an alcohol by catalytic hydrogenation, in particular in the presence of a transition metal complex, more particularly in the presence of a ruthenium (II) complex is described.
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Page/Page column 11; 12
(2013/12/03)
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- METHOD OF PRODUCING SATURATED ALKYL ESTERS/ACIDS
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Disclosed herein is the production of saturated alkyl esters or acids from furan materials. The starting compounds contain furan, ketone, and ester or acid functional groups and may be biologically-derived. The method includes hydrogenating the starting compound to form a reduced mixture. The method further includes hydrodeoxygenation of the reduced mixture to yield a saturated alkyl ester or acid. The saturated alkyl ester or acid can be unbranched or branched. The ester and acid products have a wide variety of applications and may be further processed into surfactants, solvents, and lubricants suitable for use in consumer products.
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Paragraph 0045
(2013/03/28)
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- PROCESS FOR PRODUCING DODECANE-1, 12-DIOL BY REDUCTION OF LAURYL LACTONE PRODUCED FROM THE OXIDATION OF CYCLODODECANONE
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A process for synthesizing dodecane-1,12-diol, and by-products thereof, by the reduction of lauryl lactone produced from the oxidation of cyclododecanone.
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Paragraph 00129
(2013/08/15)
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- Metal-free reductive cleavage of benzylic esters and ethers: Fragmentations result from single and double electron transfers
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The mechanisms for the reductive cleavage of benzylic esters and ethers by neutral organic electron donor 1 are different (see scheme). Products isolated from the cleavage of benzylic ethers result from the transfer of two electrons, without the intermediacy of benzyl radicals, which are believed to be intermediates in the reductive cleavage of benzylic esters. Copyright
- Doni, Eswararao,O'Sullivan, Steven,Murphy, John A.
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p. 2239 - 2242
(2013/03/28)
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- Ruthenium catalysts for hydrogenation of aromatic and aliphatic esters: Make use of bidentate carbene ligands
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Committed carbenes: The convenient application of bidentate carbene ligands is described for the hydrogenation of carboxylic acid esters. The ligand precursors are easily synthesized through the dimerization of N-substituted imidazoles with diiodomethane. The catalyst is generated in situ and exhibits good activity and functional group tolerance for the hydrogenation of aromatic and aliphatic carboxylic acid esters. Copyright
- Westerhaus, Felix A.,Wendt, Bianca,Dumrath, Andreas,Wienhoefer, Gerrit,Junge, Kathrin,Beller, Matthias
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p. 1001 - 1005
(2013/07/27)
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- Formic acid: A promising bio-renewable feedstock for fine chemicals
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In light of the growing scarcity of petroleum-based raw materials, carbon dioxide (CO2) is becoming increasing attractive as organic carbon source. In this perspective, formic acid (HCOOH) might be an interesting bio-renewable solution to store, transport, and activate carbon dioxide for the synthesis of value-added chemicals. Herein, HCOOH has been successfully used as C1 building block for the synthesis of a library of alcohols via a catalysed oxo-synthesis, under green experimental conditions. Copyright
- Mura, Manuel G.,Luca, Lidia De,Giacomelli, Giampaolo,Porcheddu, Andrea
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supporting information
p. 3180 - 3186
(2013/01/15)
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- Reductive cleavage of the Csp2-Csp3 bond of secondary benzyl alcohols: Rhodium catalysis directed by N-containing groups
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Cutting loose: 1,1-Biarylmethanol substrates undergo reductive cleavage of the C-C bond in the presence of a cationic RhIII catalyst and H 2 (see scheme; DG=directing group). Various functional groups are tolerated in the reaction system. Preliminary studies indicate that a five-membered rhodacycle intermediate, which then converts into a Rh III hydride species for the reduction, is involved in the catalytic cycle. Copyright
- Chen, Kang,Li, Hu,Lei, Zhi-Quan,Li, Yang,Ye, Wen-He,Zhang, Li-Sheng,Sun, Jian,Shi, Zhang-Jie
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p. 9851 - 9855
(2012/11/07)
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- Tandem hydroformylation/hydrogenation of alkenes to normal alcohols using Rh/Ru dual catalyst or Ru single component catalyst
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The catalyst system for tandem hydroformylation/hydrogenation of terminal alkenes to the corresponding homologated normal alcohol was developed. The reaction mechanism for the Rh/Ru dual catalyst was investigated by real-time IR monitoring experiments and 31P NMR spectroscopy, which proved the mutual orthogonality of Rh-catalyzed hydroformylation and Ru-catalyzed hydrogenation. Detailed investigation about Ru-catalyzed hydrogenation of undecanal under H2/CO pressure clarified different kinetics from the hydrogenation under H2 and gave a clue to design more active hydrogenation catalysts under H2/CO atmosphere. The solely Ru-catalyzed normal selective hydroformylation/hydrogenation is also reported.
- Takahashi, Kohei,Yamashita, Makoto,Nozaki, Kyoko
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supporting information
p. 18746 - 18757
(2013/01/15)
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- Phosphine-imidazolyl ligands for the efficient ruthenium-catalyzed hydrogenation of carboxylic esters
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The synthesis of phosphine-imidazolyl ligands 1 and 2 in good yields is presented. In combination with [{Ru(benzene)Cl2}2], ligands 1 c and 1 e formed efficient catalyst systems for the selective hydrogenation of various carboxylic esters into their corresponding primary alcohols. Furthermore, the structures of four ruthenium complexes with ligands 1 b, 1 c, 1 d, and 1 e were determined by X-ray crystallography, which showed the formation of different coordination modes depending on the ligand structure.
- Junge, Kathrin,Wendt, Bianca,Westerhaus, Felix Alexander,Spannenberg, Anke,Jiao, Haijun,Beller, Matthias
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scheme or table
p. 9011 - 9018
(2012/10/08)
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- Nickel phosphide nanocatalysts for the chemoselective hydrogenation of alkynes
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Well-defined 25 nm nickel phosphide nanoparticles act as a colloidal catalyst for the chemoselective hydrogenation of terminal and internal alkynes. Cis-alkenes are obtained in mild conditions with good conversion and selectivity. The phosphorus inserted in the Ni-P nanoparticles is critical for the selectivity of the nanocatalyst. Mechanistic investigations using isotope labeling provide insight on the reactants interaction with the nanoparticles surface. They pinpoint the occurrence of CH bond cleavage in terminal alkynes during the reaction.
- Carenco, Sophie,Leyva-Pérez, Antonio,Concepción, Patricia,Boissire, Cédric,Mézailles, Nicolas,Sanchez, Clément,Corma, Avelino
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experimental part
p. 21 - 28
(2012/07/27)
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- Radical addition of alkyl halides to formaldehyde in the presence of cyanoborohydride as a radical mediator. A new protocol for hydroxymethylation reaction
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Hydroxymethylation of alkyl halides was achieved using paraformaldehyde as a radical C1 synthon in the presence of tetrabutylammonium cyanoborohydride as a hydrogen source. The reaction proceeds via a radical chain mechanism involving an alkyl radical addition to formaldehyde to form an alkoxy radical, which abstracts hydrogen from a hydroborate anion.
- Kawamoto, Takuji,Fukuyama, Takahide,Ryu, Ilhyong
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supporting information; experimental part
p. 875 - 877
(2012/02/15)
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- Tandem rhodium-catalyzed hydroformylation-hydrogenation of alkenes by employing a cooperative ligand system
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Dual action: A multifunctional rhodium catalyst system enables the simultaneous catalysis of two distinct transformations, hydroformylation of an alkene and reduction of an aldehyde, in a highly selective manner. This one-pot/two-step process is controlled by the cooperative action of two different supramolecular ligand systems and transforms terminal alkenes into C1-chain-elongated linear alcohols. Copyright
- Fuchs, Daniela,Rousseau, Geraldine,Diab, Lisa,Gellrich, Urs,Breit, Bernhard
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supporting information; experimental part
p. 2178 - 2182
(2012/04/10)
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- Aerobic reduction of olefins by in situ generation of diimide with synthetic flavin catalysts
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A versatile reducing agent, diimide, can be generated efficiently by the aerobic oxidation of hydrazine with neutral and cationic synthetic flavin catalysts 1 and 2. This technique provides a convenient and safe method for the aerobic reduction of olefins, which proceeds with 1 equiv of hydrazine under an atmosphere of O2 or air. The synthetic advantage over the conventional gas-based method has been illustrated through high hydrazine efficiency, easy and safe handling, and characteristic chemoselectivity. Vitamin B2 derivative 6 acts as a highly practical, robust catalyst for this purpose because of its high availability and recyclability. Association complexes of 1b with dendritic 2,5-bis(acylamino)pyridine 15 exhibit unprecedented catalytic activities, with the reduction of aromatic and hydroxy olefins proceeding significantly faster when a higher-generation dendrimer is used as a host pair for the association catalysts. Contrasting retardation is observed upon similar treatment of non-aromatic or non-hydroxy olefins with the dendrimer catalysts. Control experiments and kinetic studies revealed that these catalytic reactions include two independent, anaerobic and aerobic, processes for the generation of diimide from hydrazine. Positive and negative dendrimer effects on the catalytic reactions have been ascribed to the specific inclusion of hydrazine and olefinic substrates into the enzyme-like reaction cavities of the association complex catalysts. Copyright
- Imada, Yasushi,Iida, Hiroki,Kitagawa, Takahiro,Naota, Takeshi
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experimental part
p. 5908 - 5920
(2011/07/07)
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- Regioselective ω-hydroxylation of medium-chain n-alkanes and primary alcohols by CYP153 enzymes from Mycobacterium marinum and Polaromonas sp. strain JS666
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The oxofunctionalization of saturated hydrocarbons is an important goal in basic and applied chemistry. Biocatalysts like cytochrome P450 enzymes can introduce oxygen into a wide variety of molecules in a very selective manner, which can be used for the synthesis of fine and bulk chemicals. Cytochrome P450 enzymes from the CYP153A subfamily have been described as alkane hydroxylases with high terminal regioselectivity. Here we report the product yields resulting from C5-C12 alkane and alcohol oxidation catalyzed by CYP153A enzymes from Mycobacterium marinum (CYP153A16) and Polaromonas sp. (CYP153A P. sp.). For all reactions, byproduct formation is described in detail. Following cloning and expression in Escherichia coli, the activity of the purified monooxygenases was reconstituted with putidaredoxin (CamA) and putidaredoxin reductase (CamB). Although both enzyme systems yielded primary alcohols and α,ω-alkanediols, each one displayed a different oxidation pattern towards alkanes. For CYP153A P. sp. a predominant ω-hydroxylation activity was observed, while CYP153A16 possessed the ability to catalyze both ω-hydroxylation and α,ω- dihydroxylation reactions.
- Scheps, Daniel,Honda Malca, Sumire,Hoffmann, Helen,Nestl, Bettina M.,Hauer, Bernhard
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scheme or table
p. 6727 - 6733
(2011/11/30)
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