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Godino Ojer, Marina

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Marina

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Godino Ojer

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Ciencias Experimentales

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Opportunities from Metal Organic Frameworks to Develop Porous Carbons Catalysts Involved in Fine Chemical Synthesis.
(Catalysts, 2023) Pérez Mayoral, Elena; Godino Ojer, Marina; Matos, Inés; Bernardo, María
In the last decade, MOFs have been proposed as precursors of functional porous carbons with enhanced catalytic performances by comparison with other traditional carbonaceous catalysts. This area is rapidly growing mainly because of the great structural diversity of MOFs offering almost infinite possibilities. MOFs can be considered as ideal platforms to prepare porous carbons with highly dispersed metallic species or even single-metal atoms under strictly controlled thermal conditions. This review briefly summarizes synthetic strategies to prepare MOFs and MOF-derived porous carbons. The main focus relies on the application of the MOF-derived porous carbons to fine chemical synthesis. Among the most explored reactions, the oxidation and reduction reactions are highlighted, although some examples of coupling and multicomponent reactions are also presented. However, the application of this type of catalyst in the green synthesis of biologically active heterocyclic compounds through cascade reactions is still a challenge.
Teaching chemical engineering to biotechnology students in the time of COVID-19: Assessment of the adaptation to digitalization.
(Education for Chemical Engineers, 2021) Ripoll Morales, Vanessa; Godino Ojer, Marina; Calzada Funes, Javier
With the global outbreak of COVID-19 in March 2020, there was an immediate shutdown of face-to-face classes and a sudden shift to on-line learning. Confinement required finding innovative approaches to teaching and student assessment. This paper aims to share the experience of adapting the course in Biochemical Engineering, part of the Biotechnology program at Francisco de Vitoria University (Madrid, Spain), to remote learning. A sequence of collaborative learning activities, with active student participation, was designed to replace the traditional mid-term exam. Activities were carefully implemented, considering the range of learning styles. Engineering skills, transversal competences and higher-order thinking skills were fostered through these activities. The analysis of the teaching/learning experience was based on teacher observations, academic performance and student surveys. All indicators showed that the adopted methodology had a positive impact of student performance. Student participation, especially among those repeating the course, also improved. Furthermore, students gained a more accurate and positive perception of the link between Chemical Engineering and Biotechnology, which may have a favourable impact on the teaching of Bioreactors in the coming academic year.
Porous carbons-derived from vegetal biomass in the synthesis of quinoxalines. Mechanistic insights.
(Catalysis Today, 2019) Godino Ojer, Marina; Blazquez García, R.; Matos, I.; Bernardo, M.; Fonseca, M.; Pérez Mayoral, E.
We report herein for the first-time acid biomass-derived carbons from vegetal biomass, with high developed porosity, prepared through the integrating method comprising pyrolysis and surface phosphonation, able to efficiently catalyze the synthesis of quinoxalines from 1,2-diamines and -hydroxi ketones, under aerobic conditions. The obtained results indicate that the type and number of acid sites drive the reaction in terms of conversion and selectivity. Furthermore, our experimental and theoretical observations suggest that the preferred reaction pathway for this transformation, in the presence of the investigated acid carbon catalysts, involves cascade reactions including imination reaction between reactants, successive imine-enamine and ceto-enol tautomerisms, heterocyclization followed by dehydration, and aromatization. While the acid sites seem to be a relevant role in each reaction step, the system formed by activated carbon and molecular oxygen could be behind the last oxidative reaction to give quinoxalines.
Towards selective synthesis of quinoxalines by using transition metals-doped carbon aerogels.
(Catalysis Today, 2023) Godino Ojer, Marina; Morales Torres, Sergio; Maldonado-H´odar; Pérez-Mayoral, E.
metal (TM)-carbon aerogels, where TM = Mo, Fe, Co or Cu, were found to be active and selective catalysts for the synthesis of quinoxalines 1, from o-phenylenediamine 2 and α-hydroxy ketones 3, becoming an efficient and sustainable alternative to other carbon-based catalysts or even MOF. Doping metal phase consisting of the corresponding metal oxides but also as zero-valent metals depending on the metal and carbonization temperature, and metal loading at the surface of carbon aerogel are key factors conditioning both reactivity and selectivity. Although metal oxides are probably the predominant active catalytic species, zero-valent metals nanoparticles (Cu0 or Co0) could be implied in the last dehydrogenation step of the reaction. Moreover, the additional functionalization with oxygenated surface groups (Co-1000PO catalyst) resulted on an enhanced reactivity probably due to the cooperation between both functions. Remarkably, Mo- 500 catalyst was the most efficient sample selectively leading to the quinoxaline 1a in high conversion. Finally, our results strongly suggest different operative pathways when using TM-doped carbon aerogels depending on the metallic phase at the carbon surface. While TM-doped carbon aerogels (where TM = Fe, Co, or Cu) probably act catalyzing a sequential acid-base steps and subsequent aromatization leading to the corresponding quinoxaline 1a, Mo-doped catalyst would work via the initial oxidation of α-hydroxy ketones followed by condensation-dehydration reactions.
Eco-sustainable Synthesis of N-containing Heterocyclic Systems Using Porous Carbon Catalysts.
(ChemCatChem, 2023) Pérez Mayoral, Elena; Godino Ojer, Marina; Pastrana-Martínez, Luisa M.; Morales-Torres, Sergio; Maldonado-Hódar, Francisco J.
From the most classic carbon materials (CMs) to the advanced ones, all of them integrate a promising catalyst set in terms of sustainability and energy efficiency for a greener future. Different synthetic strategies concerning to the catalytic synthesis of relevant N-containing heterocycles are herein described to address the great potential of the referred catalysts flying over what has been done and all that remains to be done. Current trends in this field involve structure-activity relationships establishment also considering the reaction mechanisms understanding and the identification of active catalytic sites, as function of both experimental datasets, emphasizing on operando characterization techniques, and theoretical studies which will significantly contribute to the design of custom-made catalysts as a new horizon.
Cobalt oxide-Carbon nanocatalysts with highly enhanced catalytic performance for the green synthesis of nitrogen heterocycles through Friedländer condensation.
(Dalton Transactions, 2019) Godino Ojer, Marina; López Peinado, Antonio J.; Maldonado Hódar, Francisco J.; Bailón García, Esther; Pérez Mayoral, Elena
A novel series of eco-sustainable catalysts developed by supporting CoO nanoparticles on different carbon supports, highly efficient in the synthesis of quinolines and naphthyridines, through the Friedländer condensation, are reported for the first time. Textural properties, dispersion and location of the Co-phase are influenced by the nature of the carbon support, Co-precursor salt and metal loading, having a significant impact on the catalytic performance. Thus, the presence of the mesopores and macropores in carbon aerogels together with the homogeneous distribution of the active phase favours the formation of product 3a as a function of the metal loading. However, an increase in the metal content when using CNTs indicates the formation of CoO aggregates and an optimal concentration of 3 wt% CoO was observed, providing the highest conversion values. The carbon-based catalysts herein reported can be considered to be a sustainable alternative having advantages such as easy preparation, superior stability and notably enhanced catalytic performance, operating at lower temperature and under solvent-free conditions.
Amino-grafted basic mesoporous silicas: a type of highly performant catalysts for the green synthesis of 2-amino-4H-chromenes.
(Catalysis Today, 2024) González Rodal, Daniel; Godino Ojer, Marina; Palomino-Cabello, Carlos; Turnes-Palomino, Gemma; López-Peinado, Antonio J.; Pérez-Mayoral, Elena
Novel series of amino-grafted mesoporous silica materials applied to the green and efficient synthesis of 2-amino-4H-chromenes, from salicylaldehydes and ethyl cyanoacetate, under mild and free-solvent conditions, is herein reported for the first time. These catalysts are easily prepared by using the post-synthetic method, by functionalizing the SBA-15 silica with the corresponding amino silanes. The observed catalytic performance is mainly controlled by the type and concentration of basic sites. The methodology herein reported could be considered as an environmentally friendly alternative for the selective chromene synthesis, which allows to achieve high yields in short reaction times using notably small amounts of the catalysts. The experimental results are also supported with theoretical calculations, which suggest that the amine groups at the silica surface are behind the observed catalytic performance with the assistance of the silica matrix.
Basolites: a type of Metal Organic Frameworks highly efficient in the one-pot synthesis of quinoxalines from a-hydroxy ketones under aerobic conditions.
(Catalysis Today, 2019) Godino Ojer, Marina; Shamzhy, Mariya; Čejka, Jiři; Pérez-Mayoral, Elena
We report here efficient synthesis of quinoxalines from ophenylendiamine and -hydroxy ketones over commercial Basolites. The concentration and type of acid centres, as CUS sites, together with the porosity of the samples strongly influence the resulting conversion and selectivity. Our results indicate a new reaction route in which tautomerization reactions are also involved.
New Insights into N-Doped Porous Carbons as Both Heterogeneous Catalysts and Catalyst Supports: Opportunities for the Catalytic Synthesis of Valuable Compounds.
(Nanomaterials, 2023) Pérez Mayoral, Elena; Godino Ojer, Marina; Ventura, Marcia; Matos, Inés
Among the vast class of porous carbon materials, N-doped porous carbons have emerged as promising materials in catalysis due to their unique properties. The introduction of nitrogen into the carbonaceous matrix can lead to the creation of new sites on the carbon surface, often associated with pyridinic or pyrrolic nitrogen functionalities, which can facilitate various catalytic reactions with increased selectivity. Furthermore, the presence of N dopants exerts a significant influence on the properties of the supported metal or metal oxide nanoparticles, including the metal dispersion, interactions between the metal and support, and stability of the metal nanoparticles. These effects play a crucial role in enhancing the catalytic performance of the N-doped carbon-supported catalysts. Thus, N-doped carbons and metals supported on N-doped carbons have been revealed to be interesting heterogeneous catalysts for relevant synthesis processes of valuable compounds. This review presents a concise overview of various methods employed to produce N-doped porous carbons with distinct structures, starting from diverse precursors, and showcases their potential in various catalytic processes, particularly in fine chemical synthesis.
Highly efficient carbon catalysts for the green synthesis of 1,5-benzodiazepines: Experimental and theoretical study.
(Catalysis Today, 2024) Godino Ojer, Marina; Ripoll Morales, Vanessa; Pastrana-Martínez, Luisa M.; Morales-Torres, Sergio; Maldonado-Hódar, Francisco J.; Pérez-Mayoral, Elena
A family of sustainable carbon catalysts with different chemical surface, active and selective for the synthesis of benzodiazepine 1 (BDZ), from o-phenylendiamine (OPD) 2 and acetone 3, under mild conditions, is reported. Catalysts were prepared by acids treatments with H2SO4 or H3PO4 of an activated carbon doped with ZnO at 3% wt (N3Zn) and, subsequently, submitted to additional thermal treatment in air. Simultaneously to the ZnO leaching, surface C-SO3 groups were generated by treatment of N3Zn with H2SO4 (N3Zn-S) whereas treatment with H3PO4 led to C-PO3 functions (N3Zn-P sample). The thermal treatment partially removes the C-SO3 groups (N3Zn-S-C sample) while C-PO3 functions were partially oxidized to C-OPO3 groups (N3Zn-P-C). Our results suggest that these chemical surface modifications of the catalysts are key on catalytic performance, pointed out the importance of the nature and distribution of acid sites at the surface. Remarkably, investigated carbon catalysts (N3Zn-S samples) were more active than the NS catalyst obtained by direct treatment of AC with H2SO4, this last mainly functionalized with C-OSO3 groups. Although the catalysts resulting of the H3PO4 treatment showed both a similar activity, some differences on selectivity to BDZ 1 were observed, attributed to certain specificity of P-functions at the surface depending on the acid strength of active sites and the reaction conditions. These results were supported by DFT calculations.