Person: Alonso Gómez, José Miguel
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First Name
José Miguel
Last Name
Alonso Gómez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Orgánica
Area
Química Orgánica
Identifiers
9 results
Search Results
Now showing 1 - 9 of 9
Item Gold-Catalyzed Cyclizations of Alkynol-Based Compounds: Synthesis of Natural Products and Derivatives(Molecules, 2011) Alcaide, Benito; Almendros, Pedro; Alonso Gómez, José MiguelThe last decade has witnessed dramatic growth in the number of reactions catalyzed by gold complexes because of their powerful soft Lewis acid nature. In particular, the gold-catalyzed activation of propargylic compounds has progressively emerged in recent years. Some of these gold-catalyzed reactions in alkynes have been optimized and show significant utility in organic synthesis. Thus, apart from significant methodology work, in the meantime gold-catalyzed cyclizations in alkynol derivatives have become an efficient tool in total synthesis. However, there is a lack of specific review articles covering the joined importance of both gold salts and alkynol-based compounds for the synthesis of natural products and derivatives. The aim of this Review is to survey the chemistry of alkynol derivatives under gold-catalyzed cyclization conditions and its utility in total synthesis, concentrating on the advances that have been made in the last decade, and in particular in the last quinquennium.Item Tuning magnetoconductivity in LaMnO3 NPs through cationic vacancy control(Nanomaterials, 2023) Hernando Grande, Antonio; Ruiz González, María Luisa; Díaz, Omar; Alonso Gómez, José Miguel; Martínez, José L.; Ayuela, Andrés; González Calbet, José María; Cortés Gil, RaquelThe inclusion of La-Mn vacancies in LaMnO3 nanoparticles leads to a noticeable change in conductivity behavior. The sample retains its overall insulator characteristic, with a typical thermal activation mechanism at high temperatures, but it presents high magnetoconductivity below 200 K. The activation energy decreases linearly with the square of the reduced magnetization and vanishes when the sample is magnetized at saturation. Therefore, it turns out that electron hopping between Mn3+ and Mn4+ largely contributes to the conductivity below the Curie temperature. The influence of the applied magnetic field on conductivity also supports the hypothesis of hopping contribution, and the electric behavior can be explained as being due to an increase in the hopping probability via spin alignment.Item 2,3‐Diodocarbazoles by a domino iodocyclization/iodo‐translocation of (3‐iodoindolyl)butynols(Advance Synthesis & Catalysis, 2022) Martín‐Mejías, Irene; Petcu, Sonia; Alonso Gómez, José Miguel; Aragoncillo Abanades, Cristina; Almendros Requena, PedroA controlled access to 1‐aryl 2,3‐diiodo‐carbazoles involving iodine transposition has been accomplished directly from acyclic precursors. The 2,3‐diiodo‐carbazole core was prone to further chemoselective decoration at C3−I or double difunctionalization.Item Straightforward Synthesis of Bis[(trifluoromethyl)sulfonyl]ethylated Isocoumarins from 2-Ethynylbenzoates(Journal of Organic Chemistry, 2023) Petcu, Sonia; Lázaro Milla, Carlos; Rodríguez, Javier; Iriepa, Isabel; Bautista-Aguilera, Óscar ; Aragoncillo Abanades, Cristina; Alonso Gómez, José Miguel; Almendros Requena, PedroHerein, we report a facile isocoumarin and isoquinolone preparation by taking advantage of an initial bis(triflyl)ethylation [triflyl = (trifluoromethyl)sulfonyl] reaction, followed by heterocyclization, which contrasts with our previous results on cyclobutene formation. The efficiency of the catalyst- and irradiation-free heterocyclization/bis(triflyl)ethylation sequence showed exquisite dependence on the electronic nature of the substituents at the 2-ethynylbenzoate(benzamide) precursors. Molecular docking of model bis(triflyl)ethylated isocoumarins on human acetylcholinesterase (hAChE) revealed promising biological activities through selective coordination on both the catalytic active site and peripheral active site.Item Platinum and Gold Catalysis: à la Carte Hydroamination of Terminal Activated Allenes with Azoles(Organic Letters, 2019) Alonso Gómez, José Miguel; Muñoz, María PazNucleophilic additions to allenes catalyzed by transition metals represent a powerful tool to obtain selective access to diverse structures with numerous applications. Reported here is a straightforward methodology to achieve selective addition of azoles to the proximal or distal carbon of activated allenes depending on the catalyst used, unravelling a gold–platinum bimetallic catalysis approach for the 1,3-double addition of azoles to activated allenes to give 1,3-bisazole derivatives, an important scaffold in medicinal and organometallic chemistry.Item Palladium-catalyzed cocyclotrimerization of arynes with a pyramidalized alkene(Chemical Communications, 2018) Alonso Gómez, José Miguel; Quiroga, Sabela; Codony, Sandra; Turcu, Andreea ; Barniol-Xicota, Marta; Pérez, Dolores; Guitián, Enrique; Vázquez, Santiago; Peña, DiegoA pyramidalized alkene and diverse arynes are generated in the presence of a Pd-catalyst to afford [2+2+2] cocycloaddition products. The metal-catalyzed 2+2+2] cocycloaddition of arynes with pyramidalized alkenes is presented. The generation of a highly reactive pyramidalized alkene in the presence of a large excess of in situ-produced arynes led to the corresponding cocyclotrimerization (1 : 2)-adducts in good yields, establishing the first example of a palladium-based reaction of a pyramidalized alkene.Item Synthesis and reactivity of a trigonal porous nanographene on a gold surface(Chemical Science, 2019) Zuzak, Rafal; Pozo, Iago; Engelund, Mads; Garcia-Lekue, Aran; Vilas-Varela, Manuel; Alonso Gómez, José Miguel; Szymonski,Marek; Guitián, Enrique; Pérez, Dolores; Godlewski,Szymon; Peña, DiegoThe synthesis of porous nanographenes is a challenging task for solution chemistry, and thus, on-surface synthesis provides an alternative approach. Here, we report the synthesis of a triporous nanographene with 102 sp2 carbon atoms by combining solution and surface chemistry. The carbon skeleton was obtained by Pd-catalyzed cyclotrimerization of arynes in solution, while planarization of the molecule was achieved through two hierarchically organized on-surface cyclodehydrogenation reactions, intra- and inter-blade. Remarkably, the three non-planar 14]annulene pores of this nanographene further evolved at higher temperatures showing interesting intra-porous on-surface reactivity.Item Synthesis of a Novel Type of 2,3’-BIMs via Platinum-Catalysed Reaction of Indolylallenes with Indoles(Chemistry A European Journal, 2018) Cooper, Lisa; Alonso Gómez, José Miguel; Eagling, Louise; Newson, Helen; Herath, Sachini; Thomson, Christopher; Lister, Andrew; Howsham, Catherine; Cox, Brian; Muñoz, María PazOptimisation, scope and mechanism of the platinum catalysed addition of indoles to indollylallenes is reported here to give 2,3-BIMs with a novel core structure very relevant for pharmaceutical industry. The reaction is modulated by electronic properties of the substituents on both indoles, with the 2,3-BIMs favoured when electron donating groups are present. Although simple at first, a complex mechanism has been uncovered that explains the different behaviour of these systems with platinum when compared with other metals (e.g. gold). Detailed labelling studies have shown Pt-catalysed 6-endo-trig cyclisation of the indollylallene as the first step of the reaction and the involvement of two cyclic vinyl-platinum intermediates in equilibrium through a platinum carbene, as the key intermediates of the catalytic cycle towards the second nucleophilic attack and formation of the BIMs.Item Heterobimetallic Catalysis: Platinum‐Gold‐Catalyzed Tandem Cyclization/C−X Coupling Reaction of (Hetero)Arylallenes with Nucleophiles(Angewandte Chemie International Edition, 2018) Alonso Gómez, José Miguel; Muñoz, Maria PazHeterobimetallic catalysis offers new opportunities for reactivity and selectivity but still presents challenges, and only a few metal combinations have been explored so far. Reported here is a Pt‐Au heterobimetallic catalyst system for the synthesis of a family of multi‐heteroaromatic structures through tandem cyclization/C−X coupling reaction. Au‐catalyzed 6‐cyclization takes place as the first fast step. Pt‐Au clusters are proposed to be responsible for the increased reactivity in the second step, that is, the intermolecular nucleophilic addition which occurs through an outer‐sphere mechanism by hybrid homogeneous‐heterogeneous catalysis.