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Hydroformylation
Kinds of Hydroformylation Terms modified by Hydroformylation Selected AbstractsChiral Diphosphite-Modified Rhodium(0) Nanoparticles: Catalyst Reservoir for Styrene HydroformylationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 22 2008M. Rosa Axet Abstract The organometallic synthesis of rhodium nanoparticles stabilized with diphosphite ligands is described. These nanoparticles were investigated as catalysts in the styrene hydroformylation reaction, and their activity and selectivity were compared with those of similar molecular complexes. NMR spectroscopic studies performed during the course of the catalytic reaction showed that the synthesized nanoparticles are not stable and produce molecular species. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Amino-phosphanes in RhI -Catalyzed Hydroformylation: New Mechanistic Insights Using D2O as Deuterium-Labeling AgentEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2006Jacques Andrieu Abstract In previous work, we have demonstrated that the dangling amino group in amino-phosphane ligands increases the rate of Rh-catalyzed styrene hydroformylation as a function of the amino group basicity and of the distance between the P and N functions. We now report additional stereochemical and mechanistic insights resulting from new catalytic experiments performed with Rh-,-P,N catalytic systems in the presence of D2O. In addition to the expected D0 product, the formation of the ,-D1 aldehyde, PhCH(CH2D)CHO was observed in all cases by 1H and 13C NMR spectroscopy, indicating that H/D exchange occurs for the rhodium-hydride complex. Minor amounts of a ,-D2 product, PhCH(CHD2)CHO, were also formed under certain conditions, demonstrating the reversibility of the olefin coordination step. The composition of the aldehyde mixture is slightly affected by the nature of the catalytic precursor or the P,N ligand used. In the specific case of the ,-P,N ligand [,-P,N = (SAr,SC)-Ph2PCH{o -C6H4Cl(Cr(CO)3)}NHPh], in combination with the [RhCl(COD)]2 precatalyst, products PhCD(CH3)CHO (,-D1) and PhCD(CH2D)CHO (,,,-D2) were also produced. This result suggests a reversible deprotonation assisted by an intramolecular H-bonding interaction between the dangling ammonium function and the carbonyl moiety. This isotopic exchange process decreases the asymmetric induction from 14 to 7,% ee when using the enantiopure version of this ligand. Aldehydes bearing a D atom on the formyl group, e.g. PhCH(CH3)CDO, were never observed. The latter observation excludes protonolysis of the rhodium-acyl intermediate as the aldehyde forming step. In addition, it also excludes a bimolecular reaction involving the rhodium-acyl and rhodium-hydride intermediates.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Desymmetrization of meso -Bicyclic Hydrazines by Rhodium-Catalyzed Enantioselective HydroformylationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 13 2008Chloée Bournaud Abstract An asymmetric hydroformylation of three meso -bicyclic hydrazines followed by the reduction of the formyl product afforded the corresponding desymmetrized optically enriched hydroxymethyl hydrazines (up to 77.5,%,ee). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Regioselective and Enantioselective Hydroformylation of DialkylacrylamidesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2010Abstract Dimethylacrylamide can be hydroformylated with very high chemo- and regioselectivity. Asymmetric hydroformylation of this substrate is possible, provided steps are taken to minimise racemisation of the aldehyde products, and this work demonstrates the effect of various conditions and variables on racemisation. Using the Landis diazaphospholane ligands up to 68% ee can be realised under very mild conditions. Other dialkylacrylamides were also hydroformylated under mild conditions giving similar or better enantioselectivities, including the Weinreb amide of acrylic acid (71% ee), and the asymmetric hydroformylation of diethylacrylamide producing the chiral aldehyde with up to 82% ee. [source] Highly Linear-Selective Hydroformylation of 1-Alkenes using Formaldehyde as a Syngas SubstituteADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Gouki Makado Abstract A highly linear-selective hydroformylation of 1-alkenes using formaldehyde without the direct use of syngas is described. One rhodium(I) complex catalyzes two processes in the overall hydroformylation of 1-alkenes using formaldehyde as the syngas substitute to give hydroformylated aldehydes with excellent regioselectivities. A high regioselectivity (linear/branched=up to 98/2) and chemical yield (up to 95%) can be achieved by the simultaneous use of two types of phosphanes as ligands. [source] Highly Efficient Rhodium Catalysts for the Asymmetric Hydroformylation of Vinyl and Allyl Ethers using C1 -Symmetrical Diphosphite LigandsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Aitor Gual Abstract Here, we describe the successful application of novel glucofuranose-derived 1,3-diphosphites in the rhodium-catalysed asymmetric hydroformylation of vinyl acetate, 2,5-dihydrofuran and 2,3-dihydrofuran. In the hydroformylation of vinyl acetate, total regioselectivity and high ee (up to 73%) were obtained. When 2,3- and 2,5-dihydrofuran were the substrates, total chemo- and regioselectivities were achieved together with ees up to 88%. These results correspond to the highest ee values reported to date in the asymmetric hydroformylation of these substrates. The HP-NMR studies of the [RhH(CO)2(L)] species (L=15 and 17) demonstrated that both ligands coordinate to the Rh centre in an eq-eq fashion. The complex [RhH(CO)2(15)] was detected as a single isomer with characteristic features of eq-eq coordination. However, the broadening of the corresponding signals indicated that this species is rapidly interchanging in solution. In contrast, complex [RhH(CO)2(17)] was detected as a mixture of two conformational isomers at low temperature due to the greater flexibility of the monocyclic backbone of this ligand. [source] Efficient Hydroformylation in Dense Carbon Dioxide using Phosphorus Ligands without Perfluoroalkyl SubstituentsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2009Ard C. Abstract Rhodium catalysts modified with triphenylphosphine, triphenyl phosphite, and tris(2,4-di- tert -butylphenyl) phosphite have been evaluated for their performance in the hydroformylation of 1-octene using carbon dioxide as the solvent. It is demonstrated that these catalysts are very efficient for the hydroformylation in carbon dioxide, although they are not designed for use in this medium. In particular, the catalyst prepared in situ from dicarbonyl(2,4-pentanedione)rhodium(I) and tris(2,4-di- tert -butyl-phenyl) phosphite gave rise to an initial turnover frequency in excess of 3×104,molaldehyde,molRh,h,1. Such a reaction rate is unprecedented for hydroformylation in supercritical carbon dioxide-rich reaction mixtures. [source] Highly Regioselective and Rapid Hydroformylation of Alkyl Acrylates Catalyzed by a Rhodium Complex with a Tetraphosphorus LigandADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2009Shichao Yu Abstract Alkyl acrylates have been hydroformylated to the linear aldehydes with high regioselectivity (linear/branch>99/1) and extraordinarily high average turnover frequencies (up to 5400,h,1) by using a rhodium complex with a tetraphosphorus ligand. This protocol is in sharp contrast to the most of other processes that favor production of the branched aldehyde (typically>95% branched for most Rh-catalyzed reaction systems). The high turnover number achieved by this new catalytic system is also remarkable considering the less reactive character of alkyl acrylates to the hydroformylation reaction conditions. [source] Tandem Metal and Organocatalysis in Sequential Hydroformylation and Enantioselective Mannich ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2009Serghei Chercheja Abstract Metal-catalysed hydroformylation is successfully combined with an organocatalysed stereoselective Mannich reaction in a tandem reaction sequence. This novel type of "tandem catalysis" allows access to complex molecular systems with high levels of enantioselectivity, using simple starting materials and an amino acid as the chiral catalyst. [source] Tandem Metal- and Organocatalysis in Sequential Hydroformylation and Enantioselective Aldol ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2007Serghei Chercheja Abstract Metal-catalysed hydroformylation is successfully combined with organocatalysed stereoselective aldol addition into a tandem reaction sequence. This novel type of "tandem catalysis" allows access to complex molecular systems with high levels of enantioselectivity, using simple starting materials and an amino acid as the chiral catalyst. [source] Retaining Catalyst Performance at High Temperature: The Use of a Tetraphosphine Ligand in the Highly Regioselective Hydroformylation of Terminal OlefinsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2007Yongjun Yan Abstract A new tetraphosphine ligand has been developed and applied in the highly regioselective hydroformylation of terminal olefins. The ligand retains high performance at high temperature when compared with its bisphosphine analogue. [source] Synthesis of 3-Substituted Furans by HydroformylationADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4-5 2006Perli Nanayakkara Abstract A simple and novel method for the synthesis of 3-substituted furans by the hydroformylation of substituted propargylic alcohols is described using rhodium acetate and triphenylphosphine in dichloromethane. The hydroformylation reaction proceeds in a regioselective manner under mild reaction conditions. This novel methodology is versatile and can be applied to the synthesis of a variety of 3-aryl-substituted furans. [source] Cover Picture: Bidentate Ligands by Self-Assembly through Hydrogen Bonding: A General Room Temperature/Ambient Pressure Regioselective Hydroformylation of Terminal Alkenes (Adv. Synth.ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-13 2005Catal. Abstract The cover picture shows a typical industrial reaction, hydroformylation of terminal alkenes, made possible in a test tube with ambient pressure and room temperature with high regioselectivities. For more details, see the Communication by Wolfgang Seiche, Alexander Schuschkowski, and Bernhard Breit on pages 1488,1494. [source] Rhodium Complexed C2 -PAMAM Dendrimers Supported on Large Pore Davisil Silica as Catalysts for the Hydroformylation of OlefinsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2005Abstract Polyamidoamine (PAMAM) dendrimers up to the third generation were grown for the first time on the surface of a large-pore (18,nm) Davisil silica support. The supported dendrimers of generations 0, 1, 2 and 3 were phosphinomethylated and complexed with rhodium. All the generations were found to be very active for the hydroformylation of olefins. The hydroformylation of 1-octene was accomplished with a turnover frequency of 1700,h,1 at 70,°C. The G(1) material was found to be the most active when the different generations were compared at 50% conversion at 70,°C [source] Rhodium-Catalyzed Asymmetric Hydroformylation of N -Allylamides: Highly Enantioselective Approach to ,2 -Amino Aldehydes,ANGEWANDTE CHEMIE, Issue 24 2010Xiaowei Zhang N -Allylamide undN -Allylsulfonamide wurden mithilfe eines Rhodium-Yanphos-Katalysators asymmetrisch hydroformyliert. Dabei wurden ,2 -Aminoaldehyde, -säuren und -alkohole mit ausgezeichneten Enantioselektivitäten erhalten (siehe Schema; TON=Umsatzzahl, acac=Acetylacetonat). [source] Supramolecular Catalyst for Aldehyde Hydrogenation and Tandem Hydroformylation,Hydrogenation,ANGEWANDTE CHEMIE, Issue 43 2009Lisa Diab Dr. Ein neuartiger Mechanismus wirkt bei der chemoselektiven Reduktion von Aldehyden und der Tandem-Hydroformylierung-Hydrierung endständiger Alkene mit dem gezeigten supramolekularen Katalysator. Dabei wird das Substrat durch Waaserstoffbrückenbindung aktiviert, und eine difunktionelle Metall-Ligand-Einheit sorgt für die Hydrierung. [source] Hydroformylation , amidocarbonylation of androstene and pregnene derivatives ,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2002Emese Nagy Abstract Androstene and pregnene derivatives were functionalized by amides with rhodium or binary rhodium,cobalt catalysts. Whereas the Rh,PPh3 catalyzed reaction results in the unsaturated amido-methylidene derivatives, the rapid hydrogenation of these compounds takes place in the presence of a basic PR3 ligand. Using a binary rhodium,cobalt system, amidocarbonylation of the steroids occurs with high chemo- and regio-selectivity. Our experiments did not support literature reports claiming the essential role of a bimetallic cluster as the active catalyst. Copyright © 2002 John Wiley & Sons, Ltd. [source] ChemInform Abstract: Supramolecular Catalyst for Aldehyde Hydrogenation and Tandem Hydroformylation,Hydrogenation.CHEMINFORM, Issue 6 2010Lisa Diab Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Rhodium-Catalyzed Hydroformylation of Cyclopropenes.CHEMINFORM, Issue 7 2009William M. Sherrill Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: A Supramolecular Catalyst for the Decarboxylative Hydroformylation of ,,,-Unsaturated Carboxylic Acids.CHEMINFORM, Issue 34 2008Tomas Smejkal Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Highly Regioselective Hydroformylation of Enamides with Phosphite Ligands.CHEMINFORM, Issue 34 2008Ourida Saidi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Biphasic Hydroformylation in Ionic Liquids: Interaction Between Phosphane Ligands and Imidazolium Triflate, Toward an Asymmetric Process.CHEMINFORM, Issue 20 2008Loic Leclercq Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Chiral N-Allylpyrroles as Versatile Substrates under Rhodium-Catalyzed Hydroformylation: Good Regio- and Diastereoselectivity at Room Temperature and High Pressure.CHEMINFORM, Issue 9 2008Roberta Settambolo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Tandem Metal- and Organocatalysis in Sequential Hydroformylation and Enantioselective Aldol Reactions.CHEMINFORM, Issue 51 2007Serghei Chercheja Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Microwaves Make Hydroformylation a Rapid Easy Process.CHEMINFORM, Issue 51 2006Elena Petricci Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis of 3-Substituted Furans by Hydroformylation.CHEMINFORM, Issue 27 2006Perli Nanayakkara Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A Highly Selective Synthesis of 3-Hydroxy-2-methylpropionamide Involving a One-Pot Tandem Hydroformylation,Hydrogenation Sequence.CHEMINFORM, Issue 17 2006Luis Garcia Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Rhodium,Tris(3,5-bis(trifluoromethyl)phenyl)phosphine Catalyzed Hydroformylation of Dienes to Dialdehydes in Supercritical Carbon Dioxide with High Activity.CHEMINFORM, Issue 19 2004Shin-ichiro Fujita Abstract For Abstract see ChemInform Abstract in Full Text. [source] Directed Regio- and Stereoselective Hydroformylation of Mono- and 1,3-Disubstituted Allylic Alcohols: A Catalytic Approach to the anti-Aldol-Retron.CHEMINFORM, Issue 18 2004Bernhard Breit Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis of Hydroquinone-, Biphenol-, and Binaphthol-Containing Aza Macroheterocycles via Regioselective Hydroformylation and Reductive Amination.CHEMINFORM, Issue 5 2004Goran Angelovski Abstract For Abstract see ChemInform Abstract in Full Text. [source] |