The Experts below are selected from a list of 573 Experts worldwide ranked by ideXlab platform
Ivana Fleischer - One of the best experts on this subject based on the ideXlab platform.
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novel ruthenium catalyst for Hydroesterification of olefins with formates
Organic and Biomolecular Chemistry, 2014Co-Authors: Irina Profir, Matthias Beller, Ivana FleischerAbstract:An alternative ruthenium-based catalyst for the Hydroesterification of olefins with formates is reported. The good activity of our system is ensured by the use of a bidentate P,N-ligand and ruthenium dodecacarbonyl. A range of formates can be used for selective alkoxycarbonylation of aromatic olefins. In addition, the synthesis of selected aliphatic esters is realized. The proposed active ruthenium complex has been isolated and characterized.
André Mortreux - One of the best experts on this subject based on the ideXlab platform.
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Palladium-catalyzed Hydroesterification of olefins with isosorbide in standard and Brønsted acidic ionic liquids
Catalysis Communications, 2015Co-Authors: Jérôme Boulanger, André Mortreux, Adeline Seingeot, Bastien Léger, Romain Pruvost, Mathias Ibert, Thomas Chenal, Mathieu Sauthier, Anne Ponchel, Eric MonflierAbstract:Abstract The palladium catalyzed Hydroesterification of 1-octene with isosorbide was studied in standard and Bronsted acidic ionic liquids as reaction media. High conversions and selectivities towards the targeted isosorbide diesters have been achieved by using a catalytic system composed of Pd(OAc) 2 and trisulfonated triphenylphosphine dissolved in 1-(4-sulfonic acid)-butyl-3-methylimidazolium tosylate. The catalytic phase can be reused several times without any significant decrease in activity and selectivity.
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Synthesis of 1,4:3,6-dianhydrohexitols diesters from the palladium-catalyzed Hydroesterification reaction.
ChemSusChem, 2014Co-Authors: Romain Pruvost, André Mortreux, Jérôme Boulanger, Bastien Léger, Mathias Ibert, Thomas Chenal, Anne Ponchel, Eric Monflier, Mathieu SauthierAbstract:The Hydroesterification of alpha olefins has been used to synthesize diesters from bio-based secondary diols: isosorbide, isomannide, and isoidide. The reaction was promoted by 0.2% palladium catalyst generated in situ from palladium acetate/triphenylphosphine/para-toluene sulfonic acid. Optimized reaction conditions allowed the selective synthesis of the diesters with high yields and the reaction conditions could be scaled up to the synthesis of hundred grams of diesters from isosorbide and 1-octene with solvent-free conditions.
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Palladium-catalyzed Hydroesterification of propene into methyl 2-methylpropanoate at room temperature and atmospheric pressure. Influence of various parameters on the activity and selectivity of the reaction
Catalysis Letters, 1998Co-Authors: Franck Bertoux, Yves Castanet, Eric Monflier, Eric Civade, André MortreuxAbstract:The Hydroesterification of propene into methyl 2-methylpropanoate by homogeneous catalytic systems consisting of palladium, copper, oxygen and acid is investigated under very mild conditions (room temperature, atmospheric pressure). From experimental results it appears that: (i) very high selectivities (up to 95%) into the branched ester can be obtained; (ii) the presence of CuCl_2 and O_2 as final reoxidant of palladium is required; (iii) the activity increases with partial pressure of O_2 in the gas phase.
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Direct Hydroesterification of ethylene with methyl formate with the new system RuCl3–NR4I–NR3: an example of catalytic activation of the CH bond of methyl formate?
J. Chem. Soc. Chem. Commun., 1994Co-Authors: Christophe Legrand, Yves Castanet, André Mortreux, Francis PetitAbstract:Upon using the simple RuCl3–NR4I–NR3 catalytic combination and dimethylformamide as solvent, an exceptionally reactive system is obtained for direct Hydroesterification of ethylene with methyl formate (turnover frequency up to 2000 h–1) in the absence of carbon monoxide.
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direct Hydroesterification of ethylene with methyl formate with the new system rucl3 nr4i nr3 an example of catalytic activation of the ch bond of methyl formate
Journal of The Chemical Society Chemical Communications, 1994Co-Authors: Christophe Legrand, Yves Castanet, André Mortreux, Francis PetitAbstract:Upon using the simple RuCl3–NR4I–NR3 catalytic combination and dimethylformamide as solvent, an exceptionally reactive system is obtained for direct Hydroesterification of ethylene with methyl formate (turnover frequency up to 2000 h–1) in the absence of carbon monoxide.
Paul E. Floreancig - One of the best experts on this subject based on the ideXlab platform.
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investigations of the scope and mechanism of the tandem Hydroesterification lactonization reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:Heating allylic and homoallylic alcohols and 2-pyridylmethyl formate in the presence of Ru3(CO)12 initiates a tandem sequence of Hydroesterification and lactonization. Mechanistic studies suggest that regioselectivity and overall reaction efficiency are governed by the relative rates of reductive elimination and β-hydride elimination for the alkylruthenium intermediates.
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synthesis of the c16 c35 fragment of integramycin using olefin Hydroesterification as a linchpin reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:The spiroketal unit of the HIV-integrase inhibitor integramycin has been prepared in an efficient and convergent manner. Key steps in this sequence include the use of ruthenium-mediated Hydroesterification reactions of homoallylic alcohols and silyl ethers, and a C,O-dianionic addition into a lactone provides the spiroketal while minimizing protecting group manipulations.
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Investigations of the Scope and Mechanism of the Tandem Hydroesterification/Lactonization Reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:Heating allylic and homoallylic alcohols and 2-pyridylmethyl formate in the presence of Ru3(CO)12 initiates a tandem sequence of Hydroesterification and lactonization. Mechanistic studies suggest that regioselectivity and overall reaction efficiency are governed by the relative rates of reductive elimination and β-hydride elimination for the alkylruthenium intermediates.
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Synthesis of the C16−C35 Fragment of Integramycin Using Olefin Hydroesterification as a Linchpin Reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:The spiroketal unit of the HIV-integrase inhibitor integramycin has been prepared in an efficient and convergent manner. Key steps in this sequence include the use of ruthenium-mediated Hydroesterification reactions of homoallylic alcohols and silyl ethers, and a C,O-dianionic addition into a lactone provides the spiroketal while minimizing protecting group manipulations.
Kei Manabe - One of the best experts on this subject based on the ideXlab platform.
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imidazole derivatives as accelerators for ruthenium catalyzed Hydroesterification and hydrocarbamoylation of alkenes extensive ligand screening and mechanistic study
Chemcatchem, 2015Co-Authors: Hideyuki Konishi, Tsuyoshi Ueda, Takashi Muto, Yayoi Yamada, Miyuki Yamaguchi, Kei ManabeAbstract:Imidazole derivatives are effective ligands for promoting the [Ru3(CO)12]-catalyzed Hydroesterification of alkenes using formates. Extensive ligand screening was performed to identify 2-hydroxymethylated imidazole as the optimal ligand. Neither carbon monoxide gas nor a directing group was required, and the reaction also showed a wide substrate generality. The Ru–imidazole catalyst system also promoted intramolecular hydrocarbamoylation to afford lactams. A Ru–imidazole complex was unambiguously analyzed by X-ray crystallography, and it had a trinuclear structure derived from one [Ru3(CO)12] and two ligands. This complex was also successfully used for Hydroesterification. The mechanism was examined in detail by using D- and 13C-labeled formates, indicating that the Hydroesterification reaction proceeds by a decarbonylation–recarbonylation pathway.
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Imidazole Derivatives as Accelerators for Ruthenium‐Catalyzed Hydroesterification and Hydrocarbamoylation of Alkenes: Extensive Ligand Screening and Mechanistic Study
ChemCatChem, 2015Co-Authors: Hideyuki Konishi, Tsuyoshi Ueda, Takashi Muto, Yayoi Yamada, Miyuki Yamaguchi, Kei ManabeAbstract:Imidazole derivatives are effective ligands for promoting the [Ru3(CO)12]-catalyzed Hydroesterification of alkenes using formates. Extensive ligand screening was performed to identify 2-hydroxymethylated imidazole as the optimal ligand. Neither carbon monoxide gas nor a directing group was required, and the reaction also showed a wide substrate generality. The Ru–imidazole catalyst system also promoted intramolecular hydrocarbamoylation to afford lactams. A Ru–imidazole complex was unambiguously analyzed by X-ray crystallography, and it had a trinuclear structure derived from one [Ru3(CO)12] and two ligands. This complex was also successfully used for Hydroesterification. The mechanism was examined in detail by using D- and 13C-labeled formates, indicating that the Hydroesterification reaction proceeds by a decarbonylation–recarbonylation pathway.
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remarkable improvement achieved by imidazole derivatives in ruthenium catalyzed Hydroesterification of alkenes using formates
Organic Letters, 2012Co-Authors: Hideyuki Konishi, Tsuyoshi Ueda, Takashi Muto, Kei ManabeAbstract:Imidazole derivatives are revealed to be effective ligands in the Ru-catalyzed Hydroesterification of alkenes using formates, affording one-carbon-elongated esters in high yields. Further, intramolecular Hydroesterification was successfully performed to give lactones for the first time. Imidazole derivatives can contribute to promote the reaction as well as to suppress the undesired decarbonylation of formate. Toxic CO gas, a directing group, and large excess alkenes are not required.
Lijun Wang - One of the best experts on this subject based on the ideXlab platform.
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CARBON-CARBON BOND CONSTRUCTION USING ELECTRON TRANSFER INITIATED CYCLIZATION REACTIONS. RUTHENIUM-CATALYZED Hydroesterification AND ITS APPLICATION TOWARDS THE SYNTHESIS OF INTEGRAMYCIN
2005Co-Authors: Lijun WangAbstract:Electron transfer initiated cyclization reactions were successfully applied to the construction of carbon-carbon bonds after tuning the chemoselectivity and reactivity of the substrates. Olefins and allenes with several different electron-donating groups served as good nucleophiles in cyclization reactions to generate various carbocycles. Cascade cyclizations involving C-C bond formation also proved to be successful. In most cases, cyclizations gave good to excellent yields with short reaction times. A general protocol has been developed for synthesizing lactones from allylic and homoallylic alcohols using ruthenium-catalyzed Hydroesterifications. The lactone synthesis only requires 1-2 steps and can be conducted in one pot. The experimental procedure is simple and the efficiency is considerably improved compared to that of multi-step sequences. Mechanistic studies with deuterium labeling showed that the competition between hydrometalation, β-hydride elimination, and reductive elimination determines the efficiency and regioselectivity of the Hydroesterification reactions. Two major fragments of integramycin have been synthesized. The synthesis of the C16-C35 spiroketal unit of integramycin was accomplished in a convergent and stereoselective manner. The sequence includes the usage of a highly efficient ruthenium-mediated Hydroesterification reaction. This sequence also demonstrates the efficiency of C,O-dianioic additions into lactones as a method for producing spiroketals in a single operation without recourse to extensive protecting group manipulations. The synthesis of the cis-decalin unit of integramycin was achieved using a cycloaddition and an allylic rearrangement as key steps. The dienyne substrate of the cycloaddition was synthesized enantioselectively in 36% yield over 9 steps. The conditions of the cycloaddition using [(naph)Rh(cod)]SbF6 were optimized and the diastereoselectivity of the cycloaddition was found to be temperature and solvent dependant.
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investigations of the scope and mechanism of the tandem Hydroesterification lactonization reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:Heating allylic and homoallylic alcohols and 2-pyridylmethyl formate in the presence of Ru3(CO)12 initiates a tandem sequence of Hydroesterification and lactonization. Mechanistic studies suggest that regioselectivity and overall reaction efficiency are governed by the relative rates of reductive elimination and β-hydride elimination for the alkylruthenium intermediates.
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synthesis of the c16 c35 fragment of integramycin using olefin Hydroesterification as a linchpin reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:The spiroketal unit of the HIV-integrase inhibitor integramycin has been prepared in an efficient and convergent manner. Key steps in this sequence include the use of ruthenium-mediated Hydroesterification reactions of homoallylic alcohols and silyl ethers, and a C,O-dianionic addition into a lactone provides the spiroketal while minimizing protecting group manipulations.
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Investigations of the Scope and Mechanism of the Tandem Hydroesterification/Lactonization Reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:Heating allylic and homoallylic alcohols and 2-pyridylmethyl formate in the presence of Ru3(CO)12 initiates a tandem sequence of Hydroesterification and lactonization. Mechanistic studies suggest that regioselectivity and overall reaction efficiency are governed by the relative rates of reductive elimination and β-hydride elimination for the alkylruthenium intermediates.
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Synthesis of the C16−C35 Fragment of Integramycin Using Olefin Hydroesterification as a Linchpin Reaction
Organic Letters, 2004Co-Authors: Lijun Wang, Paul E. FloreancigAbstract:The spiroketal unit of the HIV-integrase inhibitor integramycin has been prepared in an efficient and convergent manner. Key steps in this sequence include the use of ruthenium-mediated Hydroesterification reactions of homoallylic alcohols and silyl ethers, and a C,O-dianionic addition into a lactone provides the spiroketal while minimizing protecting group manipulations.
