Browsing by Author "Villegas, Nery Andrés"

Now showing 1 - 11 of 11
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    A DFT study of hydrogen and methane activation by B(C6F5)3/P(t-Bu)3 and Al(C6F5)3/P(t-Bu)3 frustrated Lewis pairs
    (2017) Villegas, Nery Andrés; Toro Labbé, Alejandro; Becerra, Marcos; Real Henríquez, Misael; Mora, José R.; Rincón, Luis
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    Adsorption/Desorption process of Formaldehyde onto Iron Doped Graphene : a Theoretical Exploration from Density Functional Theory Calculations.
    (2017) Cortés Arriagada, Diego; Villegas, Nery Andrés; Toro Labbé, Alejandro; Miranda Rojas, Sebastián
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    Application of low valent main group elements in small molecule activation reactions.
    (2020) Villegas, Nery Andrés; Toro Labbé, Alejandro; Schaefer, Henry F.; Pontificia Universidad Católica de Chile. Facultad de Química
    Exceptional synthetic transformations have been achieved through the years by the use of transition metal catalysts. On the contrary, only a few industrialized processes use main group based catalysts due to its low reactivity and poor recovery from the reaction media. In this thesis, a detailed computational study of the application of main group elements acting as transition metals for the activation of small molecules is presented. The hydroboration of CO2 by group 14 NacNac derived systems and the activation of H2 by low valent aluminum species are studied. Low valent main group 14 elements (Si, Ge, Sn, and Pb) bearing charge 2+ and a N-Arylisopropyl--diketiiminate ligand were used for the transformation of CO2, aimed to yield in subsequent steps formic acid derivatives. It has been found that when going down in group 14, the reaction becomes more favored. This study suggests that Pb(II) is a preponderate candidate for hydroboration of CO2. We hope this study motivates future experimental work on main group catalysis, especially using low valent lead compounds.On the other hand, for the activation of H2 by aluminyl anions, it was found that the potassium atoms that help stabilize the dimeric form of the catalysts do not play a catalytic role in the activation of the gas. To explore substituent effect in geometry, electronic structure, and reactivity, simple AlR1R – 2 species were used as a model. High-level coupled-cluster geometry and energetics were obtained for each structure. In conclusion, donation and back-donation effects were found in these structures, resembling a TM behavior. Moreover, monosubstituted aluminyl anions reported lower activation energies concerning the disubstituted systems.Exceptional synthetic transformations have been achieved through the years by the use of transition metal catalysts. On the contrary, only a few industrialized processes use main group based catalysts due to its low reactivity and poor recovery from the reaction media. In this thesis, a detailed computational study of the application of main group elements acting as transition metals for the activation of small molecules is presented. The hydroboration of CO2 by group 14 NacNac derived systems and the activation of H2 by low valent aluminum species are studied. Low valent main group 14 elements (Si, Ge, Sn, and Pb) bearing charge 2+ and a N-Arylisopropyl--diketiiminate ligand were used for the transformation of CO2, aimed to yield in subsequent steps formic acid derivatives. It has been found that when going down in group 14, the reaction becomes more favored. This study suggests that Pb(II) is a preponderate candidate for hydroboration of CO2. We hope this study motivates future experimental work on main group catalysis, especially using low valent lead compounds.On the other hand, for the activation of H2 by aluminyl anions, it was found that the potassium atoms that help stabilize the dimeric form of the catalysts do not play a catalytic role in the activation of the gas. To explore substituent effect in geometry, electronic structure, and reactivity, simple AlR1R – 2 species were used as a model. High-level coupled-cluster geometry and energetics were obtained for each structure. In conclusion, donation and back-donation effects were found in these structures, resembling a TM behavior. Moreover, monosubstituted aluminyl anions reported lower activation energies concerning the disubstituted systems.
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    Decomposition of the electronic activity in competing [5,6] and [6,6] cycloaddition reactions between C-60 and cyclopentadiene
    (2019) Villegas, Nery Andrés; Poater, Albert; Sola, Miquel.; Schaefer III, Henry F.; Toro Labbé, Alejandro
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    Double Gold Activation of 1-Ethynyl-2-(Phenylethynyl)benzene Toward 5-exo-dig and 6-endo-dig Cyclization Reactions
    (2017) Villegas, Nery Andrés; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro; Larsen, Mie Højer; Hashmi, A. Stephen
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    Reaction Electronic Flux Perspective on the Mechanism of the Zimmerman Di-π-methane Rearrangement
    (2018) Matute, Ricardo A.; Villegas, Nery Andrés; Herrera Pisani, Bárbara Andrea; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro; Pérez, Patricia; Chamorro, Eduardo; Cortés Arriagada, Diego
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    Substituent effects on the photophysical properties of amino-aurone-derivatives
    (2018) Muñoz Becerra, Karina; Villegas, Nery Andrés; Zúñiga Loyola, César Antonio; Cortés Arriagada, Diego; Toro Labbé, Alejandro
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    Symmetry-adapted reaction electronic flux in cycloaddition reactions
    (2016) Villegas, Nery Andrés; Vogt Geisse, Stefan Alexander; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro
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    Theoretical study of glycine amino acid adsorption on graphene oxide
    (2020) Rossi-Fernández, A. C.; Villegas, Nery Andrés; Guzmán Ángel, Daniela; Gutiérrez Oliva, Soledad; Ferullo, R. M.; Castellani, N. J.; Toro Labbé, Alejandro
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    Toward a Neutral Single-Component Amidinate Iodide Aluminum Catalyst for the CO2 Fixation into Cyclic Carbonates
    (2021) Saltarini, Sebastián; Villegas, Nery Andrés; Martínez, Javier; Daniliuc, Constantin G.; Matute, Ricardo A.; Gade, Lutz H.; Rojas Guerrero, René
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    Why Low Valent Lead(II) Hydride Complex Would be a Better Catalyst for CO2 Activation Than Its 14 Group Analogues?
    (2017) Villegas, Nery Andrés; Ortega Ulloa, Daniela Elena; Cortés Arriagada, Diego; Durán Guajardo, Rocío Belén; Toro Labbé, Alejandro; Yepes, Diana; Gutiérrez Oliva, Soledad