Artículos (Química Inorgánica)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10919

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Homochiral imidazolium-based dicarboxylate compounds: Structure and solution behaviour
(Elsevier, 2020-12) Caballero, Pedro; Colodrero, Rosario M.P.; Conejo Argandoña, María del Mar; Pastor Navarro, Antonio; Álvarez, Eleuterio; Montilla Ramos, Francisco Javier; Carrasco Carrasco, Carlos Jesús; Nicasio, Antonio I.; Galindo del Pozo, Agustín; Química Inorgánica; Universidad de Sevilla; Junta de Andalucía; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
Treatment of (S,S)- and (R,R)-1-(1-carboxy-2-methylpropyl)-3-(1-carboxylate-2-methylpropyl)imidazolium compounds, (S,S)-HLiPr and (R,R)-HLiPr, with the appropriate base yielded sodium, ammonium and lithium salts of the corresponding chiral anion in good yields. Compounds {Na[(S,S)-LiPr]}n (1s), {Na[(R,R)-LiPr]}n (1r), {NH4[(S,S)-LiPr]}n (2s), {NH4[(R,R)-LiPr]}n (2r), {Li[(S,S)-LiPr]}n (3s) and {Li[(R,R)-LiPr]}n (3r) were characterised by analytical and spectroscopic (IR, 1H and 13C NMR and polarimetry) methods. Specifically, 1r-3r are the first examples of homochiral compounds containing imidazolium-dicarboxylate ligands that were prepared from non-proteinogenic amino acids. In solution, NMR showed dissociation and this fact was confirmed by the good agreement found between the experimental and calculated NMR chemical shifts of the [LiPr]− anion. Interestingly, a transient carbene intermediate was proposed by DFT calculations in order to explain the solution H-D exchange observed by NMR at the C2-H atom of imidazolium ring. These compounds were also characterised by single-crystal (1s,r and 2s,r) or powder diffraction methods (3s). At the solid state, they are novel one-dimensional coordination polymers in which cations are connected via chiral 2,2′-(imidazolium-1,3-diyl)bis(3-methylbutanoate) anion. For this anion, unprecedented μ4-κ2O1, κ2O3, κ1O4 coordination mode was observed in 1s.
Synthesis of α,β-Dicarbonylhydrazones by Aerobic Manganese-Catalysed Oxidation
(Wiley, 2018-07) Carrasco Carrasco, Carlos Jesús; Montilla Ramos, Francisco Javier; Álvarez, Eleuterio; Galindo del Pozo, Agustín; Química Inorgánica; Junta de Andalucía; Universidad de Sevilla
A practical, simple, and efficient manganese-catalysed oxidation of C(sp2)−H bond in readily available β-carbonylenehydrazine under aerobic conditions has been developed. This protocol exhibits a wide range of functional group tolerance in β-carbonylenehydrazines to afford α,β-dicarbonylhydrazones. Experimental and theoretical results suggest that the reaction very likely proceeds through a radical pathway via a hydrogen-atom-transfer process promoted by a MnIII species.
Molybdenum-catalyzed asymmetric sulfoxidation with hydrogen peroxide and subsequent kinetic resolution, using an imidazolium-based dicarboxylate compound as chiral inductor
(Elsevier, 2016-09-05) Carrasco Carrasco, Carlos Jesús; Montilla Ramos, Francisco Javier; Galindo del Pozo, Agustín; Química Inorgánica; Junta de Andalucía
A catalytic system based on simple and economic molybdenum compounds and a straightforwardly prepared imidazolium-based dicarboxylate compound, as chirality inductor, was developed for the catalytic asymmetric oxidation of sulfides with hydrogen peroxide. High yields of chiral methyl phenyl sulfoxide and good enantioselectivities (up to 40% ee) were achieved utilizing one equivalent of oxidant in 1 h. By combination of the enantioselective sulfoxidation and the concomitant kinetic resolution an 83% ee was obtained, an excellent enantioselectivity value for a molybdenum catalyst.
Oxodiperoxomolybdenum complex immobilized onto ionic liquid modified SBA-15 as an effective catalysis for sulfide oxidation to sulfoxides using hydrogen peroxide
(Elsevier, 2015-10) Carrasco Carrasco, Carlos Jesús; Montilla Ramos, Francisco Javier; Bobadilla Baladrón, Luis Francisco; Ivanova, Svetlana; Odriozola Gordón, José Antonio; Galindo del Pozo, Agustín; Química Inorgánica; Ministerio de Ciencia e Innovación; Ministerio de Economía y Competitividad (MINECO). España; Junta de Andalucía
A supported ionic-liquid-phase (SILP) was prepared by the reaction of 1-methyl-3-(3-(triethoxysilyl)propyl)-1H-imidazol-3-ium chloride with a mesoporous SBA-15 silica and then an oxodiperoxomolybdenum complex was immobilized onto the obtained SILP. The resulting material, identified as SBA-15 + ImCl + MoO5, was characterized by solid state NMR (1H, 13C and 29Si), and their textural and thermogravimetric properties were determined. The SBA-15 + ImCl + MoO5 material was investigated as catalyst for the oxidation of methylphenylsulfide, as model reaction, with aqueous hydrogen peroxide as oxidant at room temperature. The presence of the molybdenum species was crucial for achieving good conversions and methanol was selected as the best solvent (conversion of 95% and selectivity toward sulfoxide 98%). The optimized reaction conditions were applied for the oxidation of several selected sulfides. In general, good catalytic activity and selectivity to sulfoxide were obtained and, remarkably, the selectivity toward sulfoxide is higher than those observed in the study of the same process carried out in [C4min][PF6] (C4mim = 1–butyl-3-methylimidazolium) and catalyzed by a molecular molybdenum complex, under the same reaction conditions. The importance of the IL-functionalization in the SBA-15 material was evidenced by recycling experiments. The SBA-15 + ImCl + MoO5 catalyst was used for the sulfoxidation of the methylphenylsulfide substrate for ten reaction cycles without a significant change in conversion, selectivity to sulfoxide and molybdenum content.
Experimental and theoretical insights into the oxodiperoxomolybdenum-catalysed sulphide oxidation using hydrogen peroxide in ionic liquids
(Royal Society of Chemistry, 2014-07) Carrasco Carrasco, Carlos Jesús; Montilla Ramos, Francisco Javier; Álvarez, Eleuterio; Mealli, Carlo; Manca, Gabriele; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
The oxidation of organic sulphides with aqueous hydrogen peroxide in ionic liquids (ILs) catalysed by oxodiperoxomolybdenum complexes was investigated. The selective formation of several sulfones was achieved using the 1 : 3 ratio of sulphide : H2O2 in [C4mim][PF6] (C4mim = 1-butyl-3-methylimidazolium) in a reaction catalysed by the [Mo(O)(O2)2(H2O)n] complex. Conversely, sulfoxides were produced with good selectivities using a 1 : 1 ratio in the same solvent in a 1 h reaction with [Mo(O)(O2)2(Mepz)2] (Mepz = methylpyrazol). The use of [C4mim][PF6] as the solvent was advantageous for two reasons: (i) the improved performance of the H2O2–IL combination; (ii) recycling of the catalyst/IL mixture without a significant diminution of conversion or selectivity. A DFT analysis using the [Mo(O)(O2)2(L)] catalysts (L = Mepz, a; 3,5-dimethylpyrazole, dmpz, b; and H2O, c) indicated that a Sharpless-type outer-sphere mechanism is more probable than a Thiel-type one. The highest barrier of the catalytic profile was the oxo-transfer step, in which the nucleophilic attack of sulphide onto the peroxide ligand occurred with formation of dioxoperoxo species. In order to yield the sulfoxide and the starting catalyst, the oxidation of the resulting dioxoperoxo species with H2O2 was found to be the most favourable pathway. Subsequently, the sulfoxide to sulfone oxidation was performed through a similar mechanism involving the [Mo(O)(O2)2(L)] catalyst. The comparable energies found for the successive two oxo-transfer steps were in agreement with the experimental formation of sulfone in both the reaction with an excess of the oxidant and the stoichiometric reaction in the absence of the oxidant. In the latter case, diphenylsulfone was isolated as the major product in the 1 : 1 combination of diphenylsulphide and [Mo(O)(O2)2(Mepz)2] in the ionic liquid [C4mim][PF6]. Also, the compounds [HMepz]4[Mo8O26(Mepz)2]·2H2O, 1, [Hdmpz]4[Mo8O26(dmpz)2]·2dmpz, 2, and [Hpz]4[Mo8O22(O2)4(pz)2]·3H2O, 3, were obtained by treating in water, stoichiometrically, dimethylsulfoxide and the corresponding [Mo(O)(O2)2(L)2] complex (L = Mepz; 3,5-dimethylpyrazole, dmpz; pyrazol, pz). The crystal structures of octanuclear compounds 1–3 were indirect proof of the formation of the theoretically proposed intermediates.
Molybdenum-catalysed oxidation of cyclohexene with hydrogen peroxide in the presence of alcohols and X-ray structures of octamolybdate [C(4)mim](4)[Mo8O26] and tetraperoxodimolybdate [Htmpy](2)[{MoO(O-2)(2)}(2)(mu-O)] complexes
(Elsevier, 2013-04) Carrasco Carrasco, Carlos Jesús; Montilla Ramos, Francisco Javier; Álvarez, Eleuterio; Herbert, Matthew; Galindo del Pozo, Agustín; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
The direct formation of a β-alcoxyalcohol from the corresponding olefin was investigated through the study of the oxidation of cyclohexene with hydrogen peroxide, as test reaction, catalysed by commercially available MoO3 in the presence of alcohols. The formation of the corresponding β-alcoxycyclohexanol was favourable in the order Me > Et > iPr > tBu, reaching approximately no yield for tBuOH. In this reaction, the lack of selectivity was due to the simultaneous formation of cyclohexane-1,2-diol by epoxide hydrolysis, a reaction that it is competitive with respect to the epoxide ring-opening reaction by the alcohol. In order to decrease the cyclohexane-1,2-diol yield, by preventing the hydrolysis reaction, several strategies were analysed and discussed. In particular, 2-methoxycyclohexanol was obtained with high yields and 99% selectivity by using as catalyst the [C4mim]4[Mo8O26] complex (C4mim = 1-butyl-3-methylimidazolium). The structure of the latter octamolybdate and also that of the tetraperoxodimolybdate [Htmpy]2[{MoO(O2)2}2(μ-O)] (tmpy = 2,4,6-trimethylpyridine) complex were determined by X-ray crystallography. The latter complex shows a μ2-oxygen bridging atom and two μ2-κ2–κ1-peroxo bridging ligands. This overall coordination assembly is unprecedented for binuclear molybdenum complexes.
Theoretical Prediction of the Electronic Properties of Bidentate Ligands (HEP2) and Synthesis of Bis(N-heterocyclic carbene) Silver and Palladium Complexes
(American Chemical Society (ACS), 2025-07) Carrasco Carrasco, Carlos Jesús; Montilla Ramos, Francisco Javier; Álvarez, Eleuterio; Galindo del Pozo, Agustín; Química Inorgánica; Universidad de Sevilla
A theoretical approach based on density functional theory (DFT) was developed to determine the electronic Huynh parameter for bidentate ligands (HEP2). The 13C chemical shift of the carbene carbon atom in the 1,3-diisopropylbenzimidazolin-2-ylidene ligand (iPr2-bimy) was calculated within the model complexes [PdBr(L2)(iPr2-bimy)]+, where L2 represents a bidentate ligand. Strong correlations were observed between the calculated and experimental chemical shifts for both N-donor and C-donor L2 ligands, with R2 values of 0.9699 and 0.9926, respectively. This DFT approach demonstrates the potential for estimating the HEP2 parameter of bidentate ligands of these types. This method was applied to estimate the HEP2 values for three bis(N-heterocyclic carbene) ligands containing carboxylate groups, (diNHCR)2–, which are explored as ligands in this study. These NHC ligands were derived from three precursor compounds: 1-(carboxymethyl)-3-((3-(carboxymethyl)-1H-imidazol-3-ium-1-yl)methyl)-1H-imidazol-3-ium bromide (1a), 1-(1-carboxyethyl)-3-((3-(1-carboxyethyl)-1H-imidazol-3-ium-1-yl) methyl)-1H-imidazol-3-ium bromide (1b), and 2-(1-(2-(1-(carboxymethyl)-1H-imidazol-3-ium-3-yl)ethyl)-1H-imidazol-3-ium-3-yl)acetate bromide (1c). They were synthesized and characterized using IR, NMR, and single-crystal X-ray crystallography (for 1a and 1c). The interaction of 1a and 1c with Ag2O in the presence of aqueous sodium hydroxide produced the complexes [Na2(H2O)8][Ag2(diCH2NHCH)2] (2a) and [Na2(H2O)8][Ag2(diC2H4NHCH)2] (2c), respectively. Complex 2a was structurally characterized, revealing a binuclear structure in which the bis-carbene ligand adopts a bridging μ-κ1(C),κ1(C′) coordination. Furthermore, 2a exhibited reactivity in transmetalation, allowing the synthesis of complex [Na2(H2O)10][Pd(diCH2NHCH)2] (3a) through a reaction with palladium acetate. Complex 3a, which was also structurally characterized, consists of a mononuclear tetracarbene species where each bis-carbene ligand coordinates in a bidentate κ2(C,C′) fashion.
Turning the Tables: Ligand-Centered Hydride Shuttling in Organometallic BIP–Al Systems
(ACS, 2025-07-24) Delgado Collado, Juan Manuel; Fernández de Córdova, Francisco José; Palma, Pilar; Cámpora Pérez, Juan; Rodríguez Delgado, Antonio; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; European Union (UE); Junta de Andalucía
The reversible storage and release of hydride equivalents remains a central challenge in the design of biomimetic redox systems. Cationic 2,6-bis(imino)pyridine organoaluminum complexes [(4-R-BIP)AlR2]+ (where R = H; R′ = Me, 1a; R′ = Et, 1b; R = Bn; R′ = Me, 1c) and their neutral 2,6-bis(imino)-4-R-dihydropyridinate counterparts [(4-R-HBIP)AlR2] 2a-c are presented as chemically reversible hydride exchangers. Interconversion between these systems is achieved through strong reducing agents such as M+[HBEt3]− (where M = Li; Na) or LiAlH4, while powerful electrophiles like B(C6F5)3 or cationic trityl salts Ph3C+ enable the reverse transformation, with the latter providing complete selectivity. Overall, this reversible hydride exchange mirrors natural NAD(P)H/NADP+ cofactor system. These findings establish a new platform for ligand-centered hydride shuttling, where the metal fragment acts as a passive modulator─inverting the traditional roles assigned to metal and ligand.
Boosting Hydrogen Release: Optimized C3N4-Supported Palladium Catalysts for Formic Acid Dehydrogenation
(John Wiley and Sons Inc, 2025-08-05) Moreno, A.; Lobo, L.; Martínez Tejada, Leidy Marcela; Bobadilla Baladrón, Luis Francisco; Ivanova, Svetlana; Domínguez Leal, María Isabel; Centeno Gallego, Miguel Ángel; Química Inorgánica; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
Carbon nitride, C3N4, was synthesized through thermal polycondensation of melamine with varying temperature and time conditions. This approach represents a cost-effective, straightforward, and environmentally friendly synthetic method with lower energy consumption to obtain hierarchically structured carbon nitride. The resulting materials were subjected to comprehensive characterization to analyze their crystalline structure, textural properties, composition, and light absorption characteristics. To evaluate their catalytic potential, the supports were impregnated with different loadings of palladium (1, 5, and 10 wt%) as the active phase and tested in the decomposition of formic acid for hydrogen production in liquid phase at mild conditions. This study revealed that the structure and composition of the C3N4 were highly dependent on the degree of polycondensation, which in turn was influenced by the temperature and the thermal synthesis process. The most promising catalytic performance was achieved with a support prepared by decomposing melamine at 650 °C for 4 h, followed by impregnation with 10 wt% Pd. Furthermore, a mechanistic study was conducted using operando DRIFTS-MS to explore the plausible catalytic pathways for synthesizing formic acid via CO2 hydrogenation using the aforementioned catalyst. This investigation highlights the potential of C3N4 as a support, further demonstrating its versatility in the circular economy of formic acid.
Understanding the Role of the Cosolvent in the Zeolite Template Function of Imidazolium-Based Ionic Liquid
(American Chemical Society, 2014-03-10) Ayala Espinar, Regla; Ivanova, Svetlana; Martínez Blanes, José María; Romero Sarria, Francisca; Odriozola Gordón, José Antonio; Química Inorgánica; Junta de Andalucía; Ministerio de Ciencia e Innovación (MICIN). España; European Union (UE)
In this work, a study for understanding the role played by [ClBmim], [BF4Bmim], [PF6Bmim], and [CH3SO3Bmim] ionic liquids (ILs) in the synthesis of zeolites is presented. The use of [ClBmim] and [CH3SO3Bmim] ILs, as reported earlier [ Chem. Eur. J. 2013, 19, 2122] led to the formation of MFI or BEA type zeolites. Contrary, [BF4Bmim] and [PF6Bmim] ILs did not succeed in organizing the Si–Al network into a zeolite structure. To try to explain these results, a series of quantum mechanical calculations considering monomers ([XBmim]) and dimers ([XBmim]2) by themselves and plus cosolvent (water or ethanol) were carried out, where X ≡ Cl–, BF4–, PF6–, or CH3SO3–. Our attention was focused on the similarities and differences among the two types of cosolvents and the relation between the structure and the multiple factors defining the interactions among the ILs and the cosolvent. Although a specific pattern based on local structures explaining the different behavior of these ILs as a zeolite structuring template was not found, the calculated interaction energies involving the Cl– and CH3SO3– anions were very close and larger than those for BF4– and PF6– species. These differences in energy can be used as an argument to describe their different behavior as structure directing agents. Moreover, the topology of the cosolvent is also an ingredient to take into account for a proper understanding of the results.
Microstructural control by freeze-casting of CaO architectures for improved and stable thermochemical energy storage performance
(Elsevier, 2025-07-30) Amghar, Nabil; Ivorra-Martinez, Juan; Perejón Pazo, Antonio; Hanaor, Dorian; Gurlo, Aleksander; Ramírez Rico, Joaquín; Pérez Maqueda, Luis Allan; Sánchez Jiménez, Pedro Enrique; Química Inorgánica; Física de la Materia Condensada; Ministerio de Ciencia e Innovación (MICIN). España
This study investigates the development of porous calcium-based monoliths via freeze-casting (FC) as a novel approach for thermochemical energy storage, particularly within the Calcium Looping (CaL) process. The freeze-casting technique enabled the fabrication of scaffolds with controlled porosity using polyvinyl alcohol (PVA) as a binder. Experimental results demonstrated that freeze-cast monoliths exhibited superior multicycle performance under various carbonation and calcination conditions. The FC-CaCO3 monolith achieved the highest residual conversion of 68.1 % under mild vacuum calcination conditions (780 °C, 0.1 bar CO2), significantly surpassing other configurations. Tests conducted in an inert atmosphere also yielded favorable results, with a conversion of 56.1 %, outperforming equivalent raw powder samples. The enhanced performance is attributed to improved CO2 interaction with the porous structure, mitigating sintering effects and preserving active surface area. Morphological observations by X-ray tomography and SEM confirmed limited particle sintering after multiple cycles, maintaining a reactive surface that supported consistent conversion rates. The pore size distribution of the material evolves upon cycling resulting in an increased microporosity, while the pore network maintains a low tortuosity (τ ~ 1.5–2.0). The addition of dopants such as ZrO2 and SiO2 did not enhance performance, as the monoliths' inherent structure provided sufficient stability. These findings highlight freeze-casting as a promising method for creating advanced porous materials suitable for energy storage applications.
Catalytic performance of NiCo-CePr oxide on FeCrAlloy micromonoliths in hydrogen production by oxidative steam reforming of ethanol
(Elsevier, 2025-10-01) Rodríguez, César; Martínez Tejada, Leidy Marcela; Centeno Gallego, Miguel Ángel; Moreno, Sonia; Molina, Rafael; Química Inorgánica; Universidad Nacional de Colombia
The conformation of a NiCo catalyst promoted by CePr on FeCrAlloy thermally pretreated micromonoliths was investigated via washcoating using a colloidal suspension of the catalytic precursor (hydrotalcite, HT) without the use of additives. A high affinity was established between the nature of the reconstructed HT and the layer of the formed alumina microstructures obtained after thermal treatment, which exhibited high material adhesion. The effect of the amount of catalyst incorporated into the sinusoidal microchannels of monoliths was also investigated. The catalytic performance was evaluated for the production of H2 from oxidative steam reforming of ethanol (OSRE) and compared with that of a powder catalyst (slurry) and an uncoated micromonolith. The results indicated notable benefits from the micromonoliths, especially when incorporating low amounts of catalyst with low layer thicknesses-LT (8 g·L-1, layer thickness ∼ 0.3 µm), achieved a hydrogen yield of 2.86 molH2·molEtOH-1, comparable to that of the powder catalyst benchmark (2.91 molH2·molEtOH-1), but with enhanced stability at 65 h and improved heat and mass transport characteristics. Overall, this study opens the way for the promising feasibility of scaling up the OSRE reaction to produce H2.
Impact of Tb4+ and morphology on the Thermal Evolution of Tb-doped TiO2 Nanostructured Hollow Spheres and Nanoparticles
(Elsevier, 2021-02-05) Colomer, M. T.; Rodríguez, E.; Morán Pedroso, María; Vattier Lagarrigue, María Florencia; Andrés, A. de; Física de la Materia Condensada; Química Inorgánica; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; European Union (UE)
Tb-doped TiO2 hollow spheres (HSs) in the range 0.0-2.0 at.% have been,synthesized by the first time to the best of our knowledge. The HSs are compared with,nanoparticles (NPs) to evaluate the impact of morphology on their physicochemical and,photoluminescence (PL) behavior upon increasing calcination temperature. After,calcination at 550ºC, the particles are anatase with a primary average size of 10.0 ± 0.2,nm for the NPs and 12.0 ± 0.2 nm for those that form the micron sized hollow spheres of,1.8 µm diameter and ca. 64 nm shell thickness. The temperature of the anatase–rutile,transition is found to be strongly dependent on the presence of Tb as well as on,morphology. Contrarily to the usual stabilization of anatase when doping with trivalent,rare-earth ions, the transition temperature is reduced when doping with Tb. The rutile,phase is further favored for the HSs compared to the NPs probably related to the low,density of the HSs and/or a more efficient packing of the nanoparticles that form those,spheres with respect to the packing of the NPs. A slight unit-cell volume decrease for the,anatase structure is observed upon Tb doping, in both the NPs and in the HSs, contrary to,the expected increment due to the larger ionic radius of Tb3+ compared to Ti4+,. In addition,,2,the intensity of the characteristic f-f Tb3+ emission bands is extremely weak both in the,anatase and rutile phases. The transition is accompanied with the emergence of an infrared,emission band centered at 810 nm related to the formation of defects during the structural,transformation providing deep levels in the gap that partly quench the f-f emissions in the,rutile phase. The results are consistent with the presence of Tb in both +3 and +4 valence,states. XPS measurements confirmed the presence of Tb3+ as well as of Tb4+ in both HSs,and NPs with a Tb4+ fraction that increases with increasing Tb doping. The large fraction,of Tb4+ present in the samples originates the weak f-f emission intensity, the slight,decrease of the cell parameters and the destabilization of the anatase phase
Selective H/D Exchange in E–H (E = Si, Ge, Sn) Bonds Catalyzed by 1,2,3-Triazolylidene-Stabilized Nickel Nanoparticles
(American Chemical Society, 2025) Molinillo, Pablo; Gálvez Del Postigo, Ana; Puyo, Maxime; Vattier Lagarrigue, María Florencia; Beltrán, Ana M.; Rendón Márquez, Nuria; Lara Muñoz, Patricia; Suárez, Andrés; Química Inorgánica; Ingeniería y Ciencia de los Materiales y del Transporte; Ministerio de Ciencia e Innovación (MICIN). España; European Union (UE)
Nickel nanoparticles (Ni·MIC) stabilized with mesoionic 1,2,3-triazolylidene (MIC) ligands were prepared via decomposition of the [Ni(COD)2] (COD = 1,5-cyclooctadiene) complex with H2 (3 bar) in the presence of 0.2 or 0.5 equiv of ligand. The obtained monodisperse and small-sized (3.2–3.8 nm) nanoparticles were characterized by high-resolution transmission electron microscopy (TEM, HRTEM) and inductively coupled plasma (ICP) analysis. Further analysis of the nickel nanoparticles by X-ray photoelectron spectroscopy (XPS) demonstrated the coordination of the MIC ligands to the metal surface. Finally, the Ni·MIC nanoparticles were applied in the isotopic H/D exchange in hydrides of group 14 elements (Si, Ge, Sn) using D2 gas under relatively mild conditions (1.0–1.8 mol % Ni, 1 bar D2, 55 °C). High and chemoselective deuterium incorporation at the E–H (E = Si, Ge, Sn) bond in these derivatives was observed.
Formation of the complete range of Ti5Si3-xGe x solid solutions via mechanically induced self-sustained reactions
(Elsevier, 2011-11) Córdoba Gallego, José Manuel; Chicardi Augusto, Ernesto; Avilés Escaño, Miguel Ángel; Gotor Martínez, Francisco José; Química Inorgánica; Ingeniería y Ciencia de los Materiales y del Transporte; Agencia Estatal de Investigación. España
The complete range of Ti5Si3-Ti5Ge 3 solid solutions was synthesised from elemental mixtures of Ti, Si, and Ge under an inert atmosphere via mechanically induced self-sustaining reactions (MSR). The stoichiometry of Ti5Si3-xGe x solid solutions was controlled by adjusting the Si/Ge ratio of the initial mixture. The chemical composition and lattice parameters of the materials confirmed that Ti5Si3-Ti5Ge 3 solid solutions with good chemical homogeneity could be produced via MSR.
V2O5/TiO2 Catalyst for Catalytic Glucose Oxidation to Formic Acid in Batch Reactor: Vanadium Species Nature and Reaction Conditions Optimization
(Springer, 2024-07-04) Álvarez Hernández, Débora; Ivanova, Svetlana; Domínguez Leal, María Isabel; Martínez Blanes, José María; Centeno Gallego, Miguel Ángel; Química Inorgánica; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE)
This study focused on the development of vanadium-based catalysts for formic acid production from glucose. The influence of different vanadium precursors on the catalytic activity of titania supported catalysts was contemplated and compared to the performance of commercial and synthesized unsupported V2O5. The obtained results reveal a successful deposition of multiple vanadium species on TiO2 as confirmed by XRD, Raman, and UV-Vis measurements. Catalyst screening identifies V5+ species as main player indicating its important oxidizing potential. Afterwards, the key reaction conditions, as temperature, time, pressure and catalyst loading, were optimized as well as the state of the catalyst after the reaction characterized.
Stepwise alkyne insertion in Au(i) acetylides: influence of the nuclearity
(Royal Society of Chemistry, 2025-02-13) Cayuela-Castillo, Juan; Fernández de Córdova, Francisco José; See, Matthew S.; Fernández, Israel; Ríos Moreno, Pablo; Química Inorgánica; Junta de Andalucía; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
The reaction between NHC-supported (NHC = N-heterocyclic carbene) gold(I) trimethylsilylacetylide complexes with NHC gold(I) hydroxide species renders different symmetrical homobimetallic Au complexes. These compounds readily undergo migratory insertion of DMAD (dimethyl acetylenedicarboxylate) at 25 °C to give the corresponding bimetallic enyne products. On the contrary, monometallic analogues require much more forcing conditions (excess of DMAD and temperature $110 °C) to give the same transformation. Experimental and computational studies reveal that the second metal fragment is responsible for the enhanced nucleophilicity of the reactive carbon atom of the acetylide C^C bond, which initially leads to a more favorable interaction with DMAD in the ratedetermining step of an unprecedented, stepwise mechanism where the lability of the Au–C bonds plays an instrumental role. The enhanced reactivity displayed by the bimetallic species was leveraged in the insertion of other substrates such as heterocumulenes.
Taking dual function materials (DFM) from the laboratory to industrial applications: a review of DFM operation under realistic integrated CO2 capture and utilization conditions
(Oxbridge Publishing House Ltd, 2024-11-19) Bahrami Gharamaleki, Soudabeh; Ramírez Reina, Tomás; Duyar, MeIis S.; Química Inorgánica
Integrated CO2 Capture and Utilization (ICCU) is gathering momentum as a promising strategy to curb harmful CO2 emissions. This approach enables the use of dilute emissions as a source of carbon for chemical synthesis through processes like methanation, reverse water gas shift, or dry reforming of methane. One ICCU approach is performed using dual function materials (DFMs), which contain adsorbent and catalytic components. While utilizing DFMs for CO2 capture and conversion can potentially enhance reaction yields and lower costs by intensifying CO2 utilization processes, the practical use of these materials under relevant industrial settings is limited. Bringing this technology to real applications demands a deep scientific exploration, particularly regarding their behavior in the presence of impurities and high levels of oxygen. Herein we critically analyze the performance of different adsorbents and catalysts under realistic conditions for CO2 capture and conversion into methane or syngas. Additionally, we discuss the stability of DFMs when exposed to various contaminants that typically poison heterogeneous catalysts and identify several research gaps in this area.
Spark plasma sintering influence on microstructure and mechanical properties of Ti:Ta/carbonitride ceramic matrix composites
(Elsevier, 2025-04) Córdoba Gallego, José Manuel; Química Inorgánica
A mechanically induced self-sustaining reaction was carried out to synthesize a Ti0.9Ta0.1C0.5N0.5/Co powdered cermets, and then they were sintered by spark plasma sintering. Microstructural parameters effects studied by image analysis, and chemical composition (studied by Rietveld analysis) on the microhardness, hardening rate, fracture toughness, transverse rupture strength, and Young’s modulus were related to the sintering conditions. The optimization of the sintering conditions (1150 ◦C, 30 MPa, and 8 min’ dwell time) drove to a homogeneous microstructure and outstanding mechanical properties. Also, the tantalum was suggested to influence the interfacial energies of the system, yielding a stronger hard phase skeleton.
Solid-state spectroscopic, thermokinetics and thermal analysis of aceclofenac coordination complexes with lanthanum and gadolinium
(Soc Brasileira Quimica, 2024-05-24) Melo, Laís D. S. M. K; Carvalho, Cláudio T.; Sánchez Jiménez, Pedro Enrique ; Sequinel, Thiago; Perejón Pazo, Antonio; Pérez Maqueda, Luis Allan ; Colman, Tiago A. D.; Química Inorgánica; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Brasil; Finaciadora de Estudos e Projetos (FINEP). Brasil
In recent years, the field of coordination chemistry has experienced a surge in interest regarding the synthesis and characterization of coordination complexes for diverse applications. This study is dedicated to investigating coordination compounds resulting from the interaction of nonsteroidal anti-inflammatory drugs (NSAIDs) with metal ions. The study research places significant emphasis on understanding the stability and thermal behavior of these coordination compounds. The utilization of thermoanalytical techniques is crucial in achieving this goal. Thermal analysis and thermokinetics provide valuable insights into the underlying mechanisms, kinetics, and energetics of these reactions, thereby facilitating the optimization of synthesis procedures. The research employs concurrent techniques, namely thermogravimetric analysis (TG) and differential scanning calorimetry (DSC), to explore the thermal stability and decomposition pathways of these coordination compounds. Thermokinetic models and optimization methodologies are subsequently applied to identify key reaction parameters. The primary aim of this research is to unveil the thermal behavior, stability, and reaction kinetics of aceclofenac coordination compounds, thus contributing significantly to the understanding of thermokinetics and thermal analysis in the domain of coordination chemistry. Specifically, this study is focused on aceclofenac coordination complexes involving lanthanum and gadolinium, with the ultimate goal of advancing the field of coordination chemistry

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