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2. Sodium Acrylate Synthesis Through CO2 and Ethylene Coupling Catalyzed by Pd: Solvent Effects and PdBr2 as a Surprisingly Suitable Precursor.

Author

Kunihiro, Kana Y., Marty, Audrey, Chahen, Ludovic, Magna, Lionel, and Asensio, Juan M.

Subjects
HOMOGENEOUS catalysis, SINGLE molecules, SODIUM, CARBON dioxide, ETHYLENE, CARBOXYLATION
Abstract

Pd‐catalyzed carboxylation of ethylene into sodium acrylate is an industrially relevant reaction that has gained increasing attention in the last years. By this process, CO2 can be transformed into a value‐added molecule in a single, high atom economy step. However, there is still some room for improvement since the productivity of the reference catalyst is rather low. A key aspect to achieve this goal concerns the good understanding of reaction mechanism. Herein, we combine experimental and DFT studies to gain some knowledge on the reactivity and catalytic performance of the Pd/dicyclohexylphosphinoethane (dcpe) system. First, we were able to understand the influence of the solvent on the reaction, and we demonstrated that DMF was the best candidate due to the more efficient formation of the Pd‐metallalactone. Moreover, we have demonstrated that highly available and less costly PdBr2 can be a suitable precursor, as PdII is reduced in situ in DMF in the presence of an excess of NaOtBu. Finally, the role of different monophosphine additives has been elucidated, which permitted us to rationally improve the catalytic performance. [ABSTRACT FROM AUTHOR]

Published
2024
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3. Long-term Event Reduction After Left Atrial Appendage Closure. Results of the Iberian Registry II

Author

López-Mínguez, José R., Nogales-Asensio, Juan M., Infante De Oliveira, Eduardo, De Gama Ribeiro, Vasco, Ruiz-Salmerón, Rafael, Arzamendi-Aizpurua, Dabit, Costa, Marco, Gutiérrez-García, Hipólito, Fernández-Díaz, José Antonio, Martín-Yuste, Victoria, Rama-Merchán, Juan Carlos, Moreno-Gómez, Raúl, Benedicto-Buendía, Amparo, and Íñiguez-Romo, Andrés

Published
2019
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4. Reducción de eventos a largo plazo tras el cierre de la orejuela izquierda. Resultados del Registro Ibérico II

Author

López-Mínguez, José R., Nogales-Asensio, Juan M., Infante De Oliveira, Eduardo, De Gama Ribeiro, Vasco, Ruiz-Salmerón, Rafael, Arzamendi-Aizpurua, Dabit, Costa, Marco, Gutiérrez-García, Hipólito, Fernández-Díaz, José Antonio, Martín-Yuste, Victoria, Rama-Merchán, Juan Carlos, Moreno-Gómez, Raúl, Benedicto-Buendía, Amparo, and Íñiguez-Romo, Andrés

Published
2019
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9. Resultados inmediatos y a más de un año en 35 pacientes consecutivos a los que se realiza cierre de orejuela izquierda con el dispositivo Amplatzer Cardiac Plug

Author

López-Mínguez, José R., Eldoayen-Gragera, Javier, González-Fernández, Reyes, Fernández-Vegas, Concepción, Fuentes-Cañamero, María E., Millán-Nuñez, Victoria, Nogales-Asensio, Juan M., Martínez-Naharro, Ana, Sánchez-Giralt, Sara, Doblado-Calatrava, Manuel, and Merchán-Herrera, Antonio

Published
2013
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15. Internal Temperature Measurements by X-Ray Diffraction on Magnetic Nanoparticles Heated by a High-Frequency Magnetic Field

Author

Faure, Stephane, primary, Mille, Nicolas, additional, Kale, Sumeet S., additional, Asensio, Juan M., additional, Marbaix, Julien, additional, Farger, Pierre, additional, Stoian, Dragos, additional, van Beek, Wouter, additional, Fazzini, Pier-Francesco, additional, Soulantica, Katerina, additional, Chaudret, Bruno, additional, and Carrey, Julian, additional

Published
2020
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21. Ultrastable Magnetic Nanoparticles Encapsulated in Carbon for Magnetically Induced Catalysis

Author

Universitat Politècnica de València. Departamento de Química - Departament de Química, European Commission, Universitat Politècnica de València, Ministerio de Economía, Industria y Competitividad, Martínez-Prieto, Luis Miguel, Marbaix, Julien, Asensio, Juan M., Cerezo-Navarrete, Christian, Fazzini, Pier-Francesco, Soulantica, Katerina, Chaudret, Bruno, Corma Canós, Avelino, Universitat Politècnica de València. Departamento de Química - Departament de Química, European Commission, Universitat Politècnica de València, Ministerio de Economía, Industria y Competitividad, Martínez-Prieto, Luis Miguel, Marbaix, Julien, Asensio, Juan M., Cerezo-Navarrete, Christian, Fazzini, Pier-Francesco, Soulantica, Katerina, Chaudret, Bruno, and Corma Canós, Avelino

Abstract

[EN] Magnetically induced catalysis using magnetic nanoparticles (MagNPs) as heating agents is a new efficient method to perform reactions at high temperatures. However, the main limitation is the lack of stability of the catalysts operating in such harsh conditions. Normally, above 500 degrees C, significant sintering of MagNPs takes place. Here we present encapsulated magnetic FeCo and Co NPs in carbon (Co@C and FeCo@C) as an ultrastable heating material suitable for high-temperature magnetic catalysis. Indeed, FeCo@C or a mixture of FeCo@C:Co@C (2:1) decorated with Ni or Pt-Sn showed good stability in terms of temperature and catalytic performances. In addition, consistent conversions and selectivities regarding conventional heating were observed for CO2 methanation (Sabatier reaction), propane dehydrogenation (PDH), and propane dry reforming (PDR). Thus, the encapsulation of MagNPs in carbon constitutes a major advance in the development of stable catalysts for high-temperature magnetically induced catalysis.

Published
2020

22. Novel nickel nanoparticles stabilized by imidazolium-amidinate ligands for selective hydrogenation of alkynes

Author

Universitat Politècnica de València. Departamento de Química - Departament de Química, European Commission, European Regional Development Fund, Universitat Politècnica de València, Université Toulouse III Paul Sabatier, Instituto de Tecnología Química UPV-CSIC, Instituto de Investigaciones Químicas US-CSIC, Ministerio de Ciencia, Innovación y Universidades, Ministerio de Economía, Industria y Competitividad, Centre National de la Recherche Scientifique, Francia, López-Vinasco, Angela M., Martínez-Prieto, Luis Miguel, Asensio, Juan M., Lecante, Pierre, Chaudret, Bruno, Cámpora, Juan, van Leeuwen, Piet W. N. M., Universitat Politècnica de València. Departamento de Química - Departament de Química, European Commission, European Regional Development Fund, Universitat Politècnica de València, Université Toulouse III Paul Sabatier, Instituto de Tecnología Química UPV-CSIC, Instituto de Investigaciones Químicas US-CSIC, Ministerio de Ciencia, Innovación y Universidades, Ministerio de Economía, Industria y Competitividad, Centre National de la Recherche Scientifique, Francia, López-Vinasco, Angela M., Martínez-Prieto, Luis Miguel, Asensio, Juan M., Lecante, Pierre, Chaudret, Bruno, Cámpora, Juan, and van Leeuwen, Piet W. N. M.

Abstract

[EN] The main challenge in the hydrogenation of alkynes into (E)- or (Z)-alkenes is to control the selective formation of the alkene, avoiding the over-reduction to the corresponding alkane. In addition, the preparation of recoverable and reusable catalysts is of high interest. In this work, we report novel nickel nanoparticles (Ni NPs) stabilized by three different imidazolium-amidinate ligands (ICy center dot(NCN)-N-(Ar); L1: Ar = p-tol, L2: Ar = p-anisyl and L3: Ar = p-ClC6H4). The as-prepared Ni NPs were fully characterized by (HR)-TEM, XRD, WASX, XPS and VSM. The nanocatalysts are active in the hydrogenation of various substrates. They present a remarkable selectivity in the hydrogenation of alkynes towards (Z)-alkenes, particularly in the hydrogenation of 3-hexyne into (Z)-3-hexene under mild reaction conditions (room temperature, 3% mol Ni and 1 bar H-2). The catalytic behaviour of Ni NPs was influenced by the electron donor/acceptor groups (-Me, -OMe, -Cl) in the N-aryl substituents of the amidinate moiety of the ligands. Due to the magnetic character of the Ni NPs, recycling experiments were successfully performed after decantation in the presence of an external magnet, which allowed us to recover and reuse these catalysts at least 3 times preserving both activity and chemoselectivity.

Published
2020

23. Ultrastable Magnetic Nanoparticles Encapsulated in Carbon for Magnetically Induced Catalysis

Author

European Research Council, Ministerio de Economía y Competitividad (España), Martínez-Prieto, Luis Miguel, Marbaix, Julien, Asensio, Juan M., Cerezo-Navarrete, Christian, Fazzini, Pier-Francesco, Soulantica, Katerina, Chaudret, Bruno, Corma, Avelino, European Research Council, Ministerio de Economía y Competitividad (España), Martínez-Prieto, Luis Miguel, Marbaix, Julien, Asensio, Juan M., Cerezo-Navarrete, Christian, Fazzini, Pier-Francesco, Soulantica, Katerina, Chaudret, Bruno, and Corma, Avelino

Abstract

Magnetically induced catalysis using magnetic nanoparticles (MagNPs) as heating agents is a new efficient method to perform reactions at high temperatures. However, the main limitation is the lack of stability of the catalysts operating in such harsh conditions. Normally, above 500 °C, significant sintering of MagNPs takes place. Here we present encapsulated magnetic FeCo and Co NPs in carbon (Co@C and FeCo@C) as an ultrastable heating material suitable for high-temperature magnetic catalysis. Indeed, FeCo@C or a mixture of FeCo@C:Co@C (2:1) decorated with Ni or Pt-Sn showed good stability in terms of temperature and catalytic performances. In addition, consistent conversions and selectivities regarding conventional heating were observed for CO2 methanation (Sabatier reaction), propane dehydrogenation (PDH), and propane dry reforming (PDR). Thus, the encapsulation of MagNPs in carbon constitutes a major advance in the development of stable catalysts for high-temperature magnetically induced catalysis.

Published
2020

29. Novel nickel nanoparticles stabilized by imidazolium-amidinate ligands for selective hydrogenation of alkynes

Author

Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Consejo Superior de Investigaciones Científicas (España), Agencia Estatal de Investigación (España), Centre National de la Recherche Scientifique (France), Université Toulouse III Paul Sabatier, López-Vinasco, Ángela M., Martínez-Prieto, Luis Miguel, Asensio, Juan M., Lecante, Pierre, Chaudret, Bruno, Cámpora, Juan, Leeuwen, P.W.N.M. van, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Consejo Superior de Investigaciones Científicas (España), Agencia Estatal de Investigación (España), Centre National de la Recherche Scientifique (France), Université Toulouse III Paul Sabatier, López-Vinasco, Ángela M., Martínez-Prieto, Luis Miguel, Asensio, Juan M., Lecante, Pierre, Chaudret, Bruno, Cámpora, Juan, and Leeuwen, P.W.N.M. van

Abstract

The main challenge in the hydrogenation of alkynes into (E)- or (Z)-alkenes is to control the selective formation of the alkene, avoiding the over-reduction to the corresponding alkane. In addition, the preparation of recoverable and reusable catalysts is of high interest. In this work, we report novel nickel nanoparticles (Ni NPs) stabilized by three different imidazolium-amidinate ligands (ICy·(Ar)NCN; L1: Ar = p-tol, L2: Ar = p-anisyl and L3: Ar = p-ClC6H4). The as-prepared Ni NPs were fully characterized by (HR)-TEM, XRD, WASX, XPS and VSM. The nanocatalysts are active in the hydrogenation of various substrates. They present a remarkable selectivity in the hydrogenation of alkynes towards (Z)-alkenes, particularly in the hydrogenation of 3-hexyne into (Z)-3-hexene under mild reaction conditions (room temperature, 3% mol Ni and 1 bar H2). The catalytic behaviour of Ni NPs was influenced by the electron donor/acceptor groups (¿Me, ¿OMe, ¿Cl) in the N-aryl substituents of the amidinate moiety of the ligands. Due to the magnetic character of the Ni NPs, recycling experiments were successfully performed after decantation in the presence of an external magnet, which allowed us to recover and reuse these catalysts at least 3 times preserving both activity and chemoselectivity.

Published
2019

32. Magnetically Induced CO2 Methanation Using Exchange‐Coupled Spinel Ferrites in Cuboctahedron‐Shaped Nanocrystals.

Author

Rivas‐Murias, Beatriz, Asensio, Juan M., Mille, Nicolas, Rodríguez‐González, Benito, Fazzini, Pier‐Francesco, Carrey, Julian, Chaudret, Bruno, and Salgueiriño, Verónica

Subjects
*METHANATION, *NANOCRYSTALS, *MAGNETIC nanoparticles, *SPINEL, *FERRITES, *CHEMICAL stability, *NICKEL ferrite
Abstract

Magnetically induced catalysis can be promoted taking advantage of optimal heating properties from the magnetic nanoparticles to be employed. However, when unprotected, these heating agents that are usually air‐sensitive, get sintered under the harsh catalytic conditions. In this context, we present, to the best of our knowledge, the first example of air‐stable magnetic nanoparticles that: 1) show excellent performance as heating agents in the CO2 methanation catalyzed by Ni/SiRAlOx, with CH4 yields above 95 %, and 2) do not sinter under reaction conditions. To attain both characteristics we demonstrate, first the exchange‐coupled magnetic approach as an alternative and effective way to tune the magnetic response and heating efficiency, and second, the chemical stability of cuboctahedron‐shaped core–shell hard CoFe2O4–soft Fe3O4 nanoparticles. [ABSTRACT FROM AUTHOR]

Published
2020
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33. Engineering Iron–Nickel Nanoparticles for Magnetically Induced CO2 Methanation in Continuous Flow.

Author

De Masi, Déborah, Asensio, Juan M., Fazzini, Pier‐Francesco, Lacroix, Lise‐Marie, and Chaudret, Bruno

Subjects
*ELECTROMAGNETIC induction, *MAGNETIC fields, *METHANATION, *CATALYTIC activity, *NANOPARTICLES, *MAGNETIC nanoparticles, *HYDROGENATION
Abstract

Induction heating of magnetic nanoparticles (NPs) is a method to activate heterogeneous catalytic reactions. It requires nano‐objects displaying high heating power and excellent catalytic activity. Here, using a surface engineering approach, bimetallic NPs are used for magnetically induced CO2 methanation, acting both as heating agent and catalyst. The organometallic synthesis of Fe30Ni70 NPs displaying high heating powers at low magnetic field amplitudes is described. The NPs are active but only slightly selective for CH4 after deposition on SiRAlOx owing to an iron‐rich shell (25 mL min−1, 25 mT, 300 kHz, conversion 71 %, methane selectivity 65 %). Proper surface engineering consisting of depositing a thin Ni layer leads to Fe30Ni70@Ni NPs displaying a very high activity for CO2 hydrogenation and a full selectivity. A quantitative yield in methane is obtained at low magnetic field and mild conditions (25 mL min−1, 19 mT, 300 kHz, conversion 100 %, methane selectivity 100 %). [ABSTRACT FROM AUTHOR]

Published
2020
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35. TIOMAX: A Spanish Multicenter Registry of the real-world use of the TItanium OptiMAX® biostent: TIOMAX: Registro Español Multicéntrico Del Biostent De Titanio OptiMAX® En La Vida Real

Author

López-Mínguez, José R., primary, Nogales-Asensio, Juan M., additional, Romani, Sebastián, additional, Rivero-Crespo, Fernando, additional, Aragón-Extremera, Victor M., additional, Jiménez-Mazuecos, Jesús M., additional, Carrasco, Fernando, additional, Oteo-Domínguez, Juan Francisco, additional, Bosa-Ojeda, Francisco, additional, and Gómez-Hospital, Joan A., additional

Published
2017
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41. TIOMAX: A Spanish Multicenter Registry of the real–world use of the TItanium OptiMAX® biostent: TIOMAX: Registro Español Multicéntrico Del Biostent De Titanio OptiMAX® En La Vida Real.

Author

López‐Mínguez, José R., Nogales‐Asensio, Juan M., Romani, Sebastián, Rivero‐Crespo, Fernando, Aragón‐Extremera, Victor M., Jiménez‐Mazuecos, Jesús M., Carrasco, Fernando, Oteo‐Domínguez, Juan Francisco, Bosa‐Ojeda, Francisco, and Gómez‐Hospital, Joan A.

Published
2018
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42. Aqueous-Phase Chemistry of η3-Allylpalladium(II) Complexes with Sulfonated N-Heterocyclic Carbene Ligands: Solvent Effects in the Protolysis of Pd–C Bonds and Suzuki–Miyaura Reactions

Author

Asensio, Juan M., Andrés, Román, Gómez-Sal, Pilar, and de Jesús, Ernesto

Abstract

The synthesis of water-soluble η3-allyl Pd(II) complexes containing sulfonated N-heterocyclic carbene (NHC) ligands of general formula [Pd(NHC)n(η3-allyl)Cl2–n] is reported (n= 1 (1) or 2 (8)). Monocarbene complexes were obtained with the most sterically hindered NHC ligands, and biscarbenes with the less sterically hindered NHCs. The behavior of the isolated complexes in water under acidic, neutral, or alkaline conditions has been studied. The complexes are rather stable in water under neutral or alkaline conditions, although displacement of the chlorido ligand by water or hydroxide occurs under these conditions. In acidic media, Pd–NHC bonds are protolysed, and it is especially noteworthy that this protolysis occurs preferentially to that of the Pd–allyl bonds in the case of the complexes with the less-sterically hindered NHC ligands. This behavior contrasts with that observed in dimethyl sulfoxide (dmso), where the Pd–allyl bonds are selectively broken upon treatment with Brönsted acids. In addition, Pd–NHC bond breaking was promoted by the addition of a strong σ-donor ligand such as cyanide. Complex 1ais an active catalyst for the Suzuki–Miyaura cross-coupling of water-soluble aryl chlorides in neat water under moderate conditions (typically, 0.5 mol % Pd and 60 °C).

Published
2024
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43. Aqueous-Phase Chemistry of η3-Allylpalladium(II) Complexes with Sulfonated N-Heterocyclic Carbene Ligands: Solvent Effects in the Protolysis of Pd-C Bonds and Suzuki-Miyaura Reactions.

Author

Asensio, Juan M., Andrés, Román, Gómez-Sal, Pilar, and de Jesús, Ernesto

Subjects
*AQUEOUS solutions, *PALLADIUM, *HETEROCYCLIC compounds, *CARBENES, *CYANIDES
Abstract

The synthesis of water-soluble η3-allyl Pd(II) complexes containing sulfonated N-heterocyclic carbene (NHC) ligands of general formula [Pd(NHC)n(η3-allyl)Cl2-n] is reported (n = 1 (1) or 2 (8)). Monocarbene complexes were obtained with the most sterically hindered NHC ligands, and biscarbenes with the less sterically hindered NHCs. The behavior of the isolated complexes in water under acidic, neutral, or alkaline conditions has been studied. The complexes are rather stable in water under neutral or alkaline conditions, although displacement of the chlorido ligand by water or hydroxide occurs under these conditions. In acidic media, Pd-NHC bonds are protolysed, and it is especially noteworthy that this protolysis occurs preferentially to that of the Pd-allyl bonds in the case of the complexes with the less-sterically hindered NHC ligands. This behavior contrasts with that observed in dimethyl sulfoxide (dmso), where the Pd-allyl bonds are selectively broken upon treatment with Brönsted acids. In addition, Pd-NHC bond breaking was promoted by the addition of a strong σ-donor ligand such as cyanide. Complex 1a is an active catalyst for the Suzuki-Miyaura cross-coupling of water-soluble aryl chlorides in neat water under moderate conditions (typically, 0.5 mol % Pd and 60 °C). [ABSTRACT FROM AUTHOR]

Published
2017
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45. Iron carbide or iron carbide/cobalt nanoparticles for magnetically-induced CO2hydrogenation over Ni/SiRAlOx catalystsElectronic supplementary information (ESI) available. See DOI: 10.1039/c9cy00437h

Author

Kale, Sumeet S., Asensio, Juan M., Estrader, Marta, Werner, Mayke, Bordet, Alexis, Yi, Deliang, Marbaix, Julien, Fazzini, Pier-Francesco, Soulantica, Katerina, and Chaudret, Bruno

Abstract

Magnetic nanoparticles have recently been used as heating agents in heterogeneously catalyzed reactions such as CO2hydrogenation into methane. In the present work, we explore the potential of heating agents presenting different heating properties in the activation of a supported catalyst based on nickel nanoparticles (NPs) (Ni/SiRAlOx) for the CO2methanation under continuous flow. Two types of Fe2.2C NPs presenting distinct heating properties have been tested. For Fe2.2C NPs displaying lower heating powers of ca.1 kW g−1, an activation of the catalyst at a magnetic field amplitude of 80 mT is necessary to achieve high conversion and selectivity, this activation step being attributed to a partial sintering of the Ni NPs. When using Fe2.2C NPs displaying much higher heating powers of 2 kW g−1as heating agents, the magnetic field amplitude required to activate the catalyst can be reduced to 48 mT. Finally, we demonstrate that hardmagnetic materials displaying very low heating power but high Curie temperatures, such as Co nanorods (NRs), can be used as relay heating agents when mixed with small amounts of softermaterials with high heating power. Thus, by mixing Co NRs with Fe2.2C NPs, excellent catalytic performances (90% of CO2and 100% CH4selectivity) have been obtained after applying only 32 mT to trigger the reaction. Once the reaction initiated, these performances are maintained even after lowering the magnetic field to 16 mT, which is advantageous in terms of energy consumption.

Published
2019
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46. Knight Shift in 13C NMR Resonances Confirms the Coordination of N-Heterocyclic Carbene Ligands to Water-Soluble Palladium Nanoparticles.

Author

Asensio, Juan M., Tricard, Simon, Coppel, Yannick, Andrés, Román, Chaudret, Bruno, and de Jesús, Ernesto

Subjects
*KNIGHT shift, *PALLADIUM, *METAL nanoparticles, *LIGAND binding (Biochemistry), *RESONANCE
Abstract

The coordination of N-heterocyclic carbene (NHC) ligands to the surface of 3.7 nm palladium nanoparticles (PdNPs) can be unambiguously established by observation of Knight shift (KS) in the 13C resonance of the carbenic carbon. In order to validate this coordination, PdNPs with sizes ranging from 1.3 to 4.8 nm were prepared by thermal decomposition or reduction with CO of a dimethyl NHC PdII complex. NMR studies after 13CO adsorption established that the KS shifts the 13C resonances of the chemisorbed molecules several hundreds of ppm to high frequencies only when the particle exceeds a critical size of around 2 nm. Finally, the resonance of a carbenic carbon is reported to be Knight-shifted to 600 ppm for 13C-labelled NHCs bound to PdNPs of 3.7 nm. The observation of these very broad KS resonances was facilitated by using Car-Purcell-Meiboom-Gill (CPMG) echo train acquisition NMR experiments. [ABSTRACT FROM AUTHOR]

Published
2017
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