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This work explores chelating capabilities of 1-butyl-2-diphenylphosphino-3-methylimidazolium hexafluorophosphate (BDPPIMPF6) as a task-specific ionic liquid (TSIL) for metal extraction/preconcentration procedures. To this end, metal extraction by BDPPIMPF6 for 21 elements (Ag, Al, As, Au, Co, Cr, Cu, Fe, Ir, Mn, Ni, Pb, Pd, Pt, Re, Rh, Ru, Sc, Ti, V, and Zn) were evaluated. This TSIL specifically forms chelating complexes with several elements of Group 10 (Pd and Pt) and Group 11 (Ag and Cu) of the Periodic Table. Chelating capabilities of BDPPIMPF6 has been exploited for developing a novel methodology for the simultaneous determination of Ag, Cu, Pd, and Pt by means of dispersive liquid-liquid microextraction and inductively coupled plasma optical emission spectrometry detection (DLLME-ICP-OES). This methodology afforded enrichment factors of 14 to 70 and limits of detection (LoD) of 0.2–2 μg L−1 for Ag, Cu, Pd and Pt. These LoD values were between 110 and 35-fold lower than those obtained by direct analyses with ICP-OES (i.e., no DLLME treatment). Finally, the proposed method has been applied to the analysis of Ag, Cu, Pd, and Pt in water and pharmaceutical products. Irrespective of matrix characteristics, quantitative recoveries were found for all the elements investigated thus highlighting methodology robustness. Financial support was provided by the Spanish Ministerio de Ciencia, Innovación y Universidades (project RED2018-102387-T) the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P, CTQ2016-80375-P, CTQ2017-82935-P and PID2019-107268GB-I00), the Generalitat Valenciana (IDIFEDER/2021/013), Medalchemy S. L. (Medalchemy-18T) and the University of Alicante (VIGROB-050; UADIF17-42 UAUSTI16-02, VIGROB-068 and UAUSTI21-05). David Lledó thanks the Spanish Ministerio de Ciencia, Innovación y Universidades for the fellowship (FPU15/00097).

A novel base-metal multifunctional nanomagnetic catalyst is prepared by the immobilization of tungstate anions onto γ-Fe2O3 supported with imidazolium moieties. The (γ-Fe2O3-Im-Py)2WO4 was fully characterized using FT-IR, XPS, TEM, FESEM, ICP, TGA, VSM and XRD and used as a multifunctional heterogeneous catalyst for the synthesis of 2-amino-3-cyano-4H-chromenes via a multicomponent tandem oxidation process starting from alcohols under solvent-free conditions. During this process, tungstate catalyzes the oxidation of a wide range of alcohols in the presence of TBHP as a clean source. The in-situ formed aldehydes are condensed with malononitrile and β-dicarbonyl compounds/naphthols/4-hydroxycumarin through promotion by pyridine and imidazolium moieties of the catalyst. By this method, a variety of 2-amino-3-cyano-4H-chromenes are generated in good to high yields from alcohols as inexpensive and easily available starting materials. The catalyst is recovered easily by the aid of an external magnetic field and reused in five successive runs with insignificant decreasing activity.

In this study, ZnCo2O4/g-C3N4/Cu is synthesized as a new and highly effectual solar light-driven heterogeneous photocatalyst. The prepared photocatalyst is characterized using FT-IR, XRD, XPS, DRS, FESEM, TEM, EDS, and elemental mapping techniques. The performance of ZnCo2O4/g-C3N4/Cu is studied towards the metronidazole (MNZ) degradation under solar light irradiation. The kinetics of MNZ degradation and efficacy of the operational parameters comprising the initial MNZ amount (10–30 mg L−1), photocatalyst dosage (0.005–0.05 g L−1), pH (3–11), and contact time (5–30 min) on the MNZ degradation process are investigated. Surprisingly, the ZnCo2O4/g-C3N4/Cu nanocomposite presents a privileged photocatalytic performance towards the MNZ degradation under solar light irradiation. The enhanced photocatalytic activity of this photocatalyst can be ascribed to the synergistic optical effects of ZnCo2O4, g-C3N4, and Cu. The value of band gap energy for ZnCo2O4/g-C3N4/Cu is estimated to be 2.3 eV based on the Tauc plot of (αhν)2 vs. hν. The radical quenching experiments confirm that the superoxide radicals and holes are the principal active species in the photocatalytic degradation of MNZ, whereas the hydroxyl radicals have no major role in such degradation. The as-prepared photocatalyst is simply isolated and recycled for at least eight runs without noticeable loss of the efficiency. Using the natural sunlight source, applying a very low amount of the photocatalyst, neutrality of the reaction medium, short reaction time, high efficiency of the degradation procedure, utilizing air as the oxidant, low operational costs, and easy to recover and reuse of the photocatalyst are the significant highlights of the present method. It is supposed that the current investigation can be a step forward in the representation of an efficacious photocatalytic system in the treatment of a wide range of contaminated aquatic environments. Financial support of this project by University of Birjand Research Council is appreciated. The authors also thank the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (project PID2019-107268GB-I00) and the University of Alicante.

In this review, new synthetic methods for the preparation of 2H-isoindoles based on ring closure reactions, isoindoline aromatization and ring transformations are discussed. The resulting 2H-isoindoles can be isolated or in situ trapped with dienophiles to give the corresponding Diels-Alder adducts. We gratefully acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades (projects CTQ2016-81893REDT, and RED2018-102387-T) the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P, CTQ2016-80375-P, CTQ2017-82935-P and PID2019-107268GB-I00), Generalitat Valenciana (CIDEGENT/2020/058) and the University of Alicante.

The synthesis of 3,3'‐bioxindoles employing deacylative alkylations (DaA) in one‐pot process, where the 3‐bromooxindoles are generated in situ, is described. Good yields and moderate diastereoselections are obtained. By the modification of this procedure the synthesis of pure 3‐bromooxindoles through a deacylative bromination (DaB) is achieved. These bromides are efficiently employed in a photoredox dimerization process to get the desired 3,3'‐bioxindoles in good yields and low diastereoselections. In this single‐electron‐transfer (SET) mechanism the presence of a high quantum‐yield iridium(III) complex ensures high conversions in short reaction times., We gratefully acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades (projects CTQ2016‐81893REDT, and RED2018‐102387‐T) the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016‐76782‐P, CTQ2016‐80375‐P and CTQ2017‐82935‐P), the Generalitat Valenciana (PROMETEOII/2014/017), the University of Alicante, and Gobierno de Aragón (Group E06_17R and project LMP148_18). A. O.‐M. thanks MINECO for a predoctoral fellowship.

A bimetallic PdCu supported on amine functionalized ZIF-67 is shown to be efficient catalyst in Sonogashira-Hagihara coupling reaction of aryl iodides at room temperature and aryl bromides at 40 ºC. In addition, the catalyst is used in the reduction of 4-nitrophenol (4-NP) at room temperature. The analyses of several experiments are developed in order to demonstrate the existence of synergetic affects between Pd, Cu and Co particles in the named reactions. The stability and reusability of this catalyst are also assessed and its efficiency is compared with other reported catalysts in the same transformations. The authors are grateful to Institute for Advanced Studies in Basic Sciences (IASBS) Research Council and Iran National Science Foundation (INSF-Grant number of 4003055) for support of this work. We are also thankful for financial support to the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013–43446-P and CTQ2014–51912-REDC), the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016–76782-P, CTQ2016–80375-P, CTQ2017–82935-P and PID2019–107268GB-I00), the Generalitat Valenciana (IDIFEDER/2021/013) and the University of Alicante.

The multicomponent 1,3-dipolar cycloaddition of different 1,2-diaza-1,3-dienes with in-situ-generated azomethine ylides produces 1,2,4-triazepines or pyrrolidines by [3+4] or [3+2] cycloadditions, respectively. The regioselectivity is controlled by the electron-withdrawing group bound to the azo moiety of the 1,2-diaza-1,3-diene, which promotes exclusively the [3+4] cycloaddition. When the electron-withdrawing group is replaced with a phenyl group, only a [3+2] cycloaddition occurs. The Spanish authors thank the Spanish Ministerio de Ciencia e Innovación (MICINN) (projects CTQ2010-20387, and Consolider Ingenio 2010, CSD2007-00006), the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P, and CTQ2014-51912-REDC), Fondos Europeos para el Desarrollo Regional (FEDER), the Generalitat Valenciana (PROMETEO 2009/039 and PROMETEOII 2014/017), and the University of Alicante, for financial support. The Italian authors gratefully acknowledge financial support from the University of Urbino “Carlo Bo”, and the PhD Programs of the Italian Ministero dell'Università, dell'Istruzione e della Ricerca.

Azomethine ylides, generated from imine-derived O-cinnamyl or O-crotonyl salicylaldeyde and α-amino acids, undergo intramolecular 1,3-dipolar cycloaddition, leading to chromene[4,3-b]pyrrolidines. Two reaction conditions are used: (a) microwave-assisted heating (200 W, 185 °C) of a neat mixture of reagents, and (b) conventional heating (170 °C) in PEG-400 as solvent. In both cases, a mixture of two epimers at the α-position of the nitrogen atom in the pyrrolidine nucleus was formed through the less energetic endo-approach (B/C ring fusion). In many cases, the formation of the stereoisomer bearing a trans-arrangement into the B/C ring fusion was observed in high proportions. Comprehensive computational and kinetic simulation studies are detailed. An analysis of the stability of transient 1,3-dipoles, followed by an assessment of the intramolecular pathways and kinetics are also reported. Financial support was provided by the Brasilian Universiade Federal do Rio de Janeiro (UFRJ), the Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), by the Spanish Ministerio de Ciencia e Innovación (MICINN) (projects CTQ2010-20387, Consolider Ingenio 2010, CSD2007-00006), the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P, CTQ2014-51912-REDC, and CTQ2013-45415-P), the Fondos Europeos para el Desarrollo Regional (FEDER), the Generalitat Valenciana (PROMETEO 2009/039 and PROMETEOII/2014/017), the Basque Government (GV/EJ, grant IT-324-07), and the Universities of Alicante and of the Basque Country (UPV/EHU) (UFI11/22 QOSYC).

The organocatalytic activities of highly substituted proline esters obtained through asymmetric [3+2] cycloadditions of azomethine ylides derived from glycine iminoesters have been analyzed by 19F NMR and through kinetic isotope effects. Kinetic rate constants have been determined for unnatural proline esters incorporating different substituents. It has been found that exo-L and endo-L unnatural proline methyl esters yield opposite enantiomers in aldol reactions between cyclic ketones and aromatic aldehydes. The combined results reported in this study show subtle and remote effects that determine the organocatalytic behavior of these synthetic but readily available amino acid derivatives. These data can be used as design criteria for the development of new pyrrolidine-based organocatalysts. Financial support was provided by the Spanish Ministerio de Economía y Competitividad (MINECO) and the Fondo Europeo de Desarrollo Regional (FEDER) (projects CTQ2010-16959/BQU, CTQ2012-35535, CTQ2013-40855-R, CTQ2007-62771/BQU, CTQ2010-20387, CTQ2010-17436, and Consolider-Ingenio CSD2007-00006), the University of the Basque Country (UPV/EHU, UFI11/22 QOSYC), the Basque Government (GV/EJ, grant IT-324-07), the Generalitat Valenciana-FEDER (PROMETEO/2009/039), the Gobierno de Aragón-FSE (research group E40), and the University of Alicante. M. d. G. R. thanks the Donostia International Physics Center (DIPC) for a postdoctoral contract. M. S. and L. C. gratefully thank MINECO for a contract funding their PhD projects.

The more advantageous hepatitis C virus (HCV) inhibitors (most of them incorporating polysubstituted prolines or pyrrolidines) are detailed in this paper. The improvement of current treatments by combination of antiviral drugs is the driving force of this race to reduce the fast proliferation of this virus. The enhancement of efficiency in short periods of treatment is crucial in the economical point of view and for the hope of all infected people. New protease or polymerase inhibitors have been recently developed in order to substitute the traditional highly toxic PEG-interferon α-2b/ribavirin tandem. The contribution of our group in this field concerns the elaboration of the first and second generation GSK polymerase inhibitors through enantioselective processes based on silver(I)- and gold(I)-catalyzed 1,3-dipolar cycloadditions of azomethine ylides. Cet article décrit les inhibiteurs du virus de l’hépatite C (VHC) les plus efficaces (la plupart incorporant des prolines et pyrrolidines polysubstituées). L’amélioration des traitements actuels par une combinaison de médicaments antiviraux est le moteur de cette course pour réduire la prolifération rapide du virus. L’augmentation de l’efficacité sur de courtes périodes de traitement est cruciale du point de vue économique et pour l’espoir des personnes infectées. De nouveaux inhibiteurs de la protéase ou de la polymérase ont été récemment mis au point dans le but de remplacer le tandem traditionnel PEG-interféron α-2b/ribavirin hautement toxique. La contribution de notre groupe dans ce domaine concerne l’élaboration des première et seconde générations des inhibiteurs de polymérase GSK, grâce à des procédés énantiosélectifs basés sur des cycloadditions 1,3-dipolaires d’ylures d’azométhine catalysés par de l’argent(I) et de l’or(I). This work has been supported by the DGES of the Spanish Ministerio de Ciencia e Innovación (MICINN) (Consolider INGENIO 2010 CSD2007-00006, CTQ2007-62771/BQU, CTQ2007/67528, CTQ2010-20387), FEDER, the Hispano-Brazilian project PHB2008-0037-PC, the Generalitat Valenciana (PROMETEO/2009/039), the Basque government (Grant IT-324-07), and the University of Alicante.

WOS: 000449934300013, A series of prolinate and N-amidocarbothiolprolinate derivatives based on a fused pyrrole-3,4-dione core, bearing indole ring systems, are prepared from the corresponding amino acid and an aldehyde via thermal 1,3-dipolar cycloaddition of azomethine ylides and condensation with benzoylisothiocyanate. Products are fully characterized by NMR, FT-IR, MS, and an X-ray crystal structure. The prepared compounds are screened for their antibacterial activity against a range of Gram-positive and Gram-negative bacteria and their antimycobacterial activity against M. tuberculosis H37Rv strain. In addition, two selected target compounds are evaluated for cytotoxicity, apoptosis, and anti-inflammatory effects on MCF-7 (breast carcinoma) cell lines. The incorporation of indole ring and -C(O)NHC(S)- moiety resulted to be beneficial since the biological point of view. [GRAPHICS], Mersin University, Research Foundation [BAP 2015-AP2-1342], We would like to thank Mersin University, Research Foundation (Project No: BAP 2015-AP2-1342) for financial support.

Fundamentos: en la actualidad existen numerosas afecciones, sobre todo oculares, causadas por la exposición continuada de luz perteneciente al rango ultravioleta, la cual se encuentra fuera del espectro visible. Este estudio se centra en revisar la bibliografía existente relacionada con la posibilidad de protección frente a dicha radiación mediante el uso de lentes de contacto con bloqueadores UV. Por ello, Óptica y Optometría debe tomar conciencia sobre la peligrosidad que ello conlleva con el fin de aconsejar bajo argumentos evidenciados científicamente. Objetivo: identificar la utilidad de la incorporación de bloqueadores UV en lentes de contacto blandas. Métodos: revisión bibliográfica de artículos científicos encontrados en las bases de datos Pubmed, Scielo y Scopus, publicados entre 2014 y 2021, en español y en inglés. Tras establecer una estrategia de búsqueda y evaluar la calidad de las investigaciones obtenidas, se incluyeron un total de diecisiete estudios. Resultados: los resultados se categorizan en varios dominios: clasificación de lentes de contacto con protección UV según la FDA, bloqueadores UV, mejores LC del mercado, alternativas de protección y otras aplicaciones paralelas. Todos los estudios señalan alguna conexión entre las lentes de contacto con bloqueadores UV y la protección que estas ofrecen. Conclusiones: este trabajo muestra diferentes beneficios obtenidos mediante la inclusión de bloqueadores UV en las lentes de contacto. Su sencillez y posibilidad de uso constante las postulan como las mejores alternativas en cuanto a protección de la salud ocular.

In this thesis, different cycloaddition reactions, such as the enantioselective 1,3-dipolar-cycloaddition, which takes place between in situ generated stabilized azomethine ylides, and electrophilic alkenes, and the diastereoselective multicomponent reactions Amine-Aldehyde-Dienophile (AAD) or Phosphoramidate-Aldehyde-Dienophile (PAD) are described. In Chapter 1, an asymmetric 1,3-dipolar cycloaddition reaction involving an imino ester with tert-butyl acrylate was carried out using a silver(I) complex with double chirality, formed from a chiral phosphoramidite and chiral silver binolphosphate(I). The goal of this reaction is to synthesize key enantiomerically enriched structures to access the GSK-third generation of HCV inhibitors. In Chapter 2, the synthesis of polysubstituted cyclohex-2-enylamines using the multicomponent Amine-Aldehyde-Dienophile reaction involving benzyl or 4-methoxybenzylamine, is described. The study the diastereoselective version, employing commercially available chiral benzylic amines, or even a maleimide with the chiral information at the nitrogen atom, are also reported. In Chapter 3, the synthesis of polysubstituted cyclohex-2-enylamines derivatives using the multicomponent Phosphoramidate-Aldehyde-Dienophile (PAD), is described. Several series of N-substituted phosphoramidates reacted with α,β-unsaturated aldehydes, bearing hydrogen atoms at the γ-position, in good yields.

Esta memoria consta de una introducción general y tres capítulos. En la introducción general, se muestra la importancia del anillo de oxindol, describiendo productos naturales o con actividad biológica que lo contienen en su estructura y comentando algunas de sus aplicaciones biológicas más relevantes. Además, se detallan diferentes técnicas para la síntesis de derivados de oxindol, destacando las metodologías que emplean la alquilación desacilativa. En el capítulo I se muestra una alquilación desacetilativa de derivados de 3-acetil-3-alquil-2-oxindoles con alquenos electrofílicos. En el capítulo II se describe la síntesis de derivados de 2-oxindoles 3,3-disustituidos a través de la alquilación desacetilativa usando haluros de alquilo y alquenos electrofílicos y mediante la alilación desacetilativa catalizada por paladio usando alcoholes alílicos. Finalmente, en el capítulo III, se estudia la reacción aldólica desacetilativa entre 3-fluorooxindoles y aldehídos.

En esta tesis doctoral se ha estudiado la reacción 1,3-dipolar con iluros de azometino y diferentes dipolarófilos para la síntesis de compuestos ópticamente activos, usando diferentes complejos metálicos compuestos por sales de plata y cobre y diversos ligandos quirales. También se ha estudiado la reacción 1,3-dipolar térmicamente para la funcionalización de grafeno, y posterior uso de dicha funcionalización como soporte de un complejo metálico, el cual fue empleado en catálisis heterogénea.

La tesis doctoral está dividida en una introducción general y cuatro capítulos. En la introducción general, se describen diferentes productos naturales y derivados sintéticos que contienen un núcleo de oxindol en su estructura junto a comentarios sobre sus actividades biológicas. Además, también están incluidas diversas metodologías de síntesis para la síntesis de estos derivados de oxindol junto a una explicación general sobre el proceso de alquilación desacetilativa. Los capítulos se han desarrollado con una breve introducción, una propuesta de objetivos, comentarios y discusión de los resultados obtenidos en las investigaciones finalizando con las conclusiones obtenidas. El Capítulo 1 trata sobre la síntesis de 2-oxindoles 3,3-disustitutidos a través de un proceso de alquilación desacetilativa utilizando halogenuros de alquilo. El Capítulo 2 describe la alilación y la alilación desacetilativa catalizada por paladio de los derivados de 2-oxindol utilizando alcoholes alílicos no activados. En el Capítulo 3 está incluida la síntesis de 3-fluoro-2-oxindoles combinando las metodologías descritas en los dos anteriores capítulos. Finalmente, en el Capítulo 4, se desarrolla la alquilación fotocatalizada de olefinas electrofílicas a través de sulfinatos de zinc bencílicos y alquílicos.

En esta tesis doctoral se ha estudiado los iluros de azometino generados in situ en reacciones de cicloadición 1,3-dipolar y diferentes dipolarófilos para la síntesis multicomponente (libre de metales) de derivados de indolizidina a partir de pipecolinatos, aldehídos y dipolarofilos de forma térmica, y también a partir de ácido pipecólico de forma descarboxilada. También se ha estudiado la reacción de cicloadición 1,3-dipolar térmica multicomponente entre iluros de azometino no activados generados in situ a partir de aminas, aldehídos aromáticos y alquenos electrofílicos para generar derivados de pirrolidina.Además, se describe la síntesis de pirrolizidinas diastereoméricamente enriquecidas a partir de nitroprolinatos enantioméricamente puros a través de una cicloadición 1,3- dipolar multicomponente catalizada por una sal de plata y, por otro lado, una reacción de Amina-Aldehído-Dienófilo (AAD) para sintetizar estructuras ciclohex-2-en-1-ilprolinato como diastereoisómero enantiopuro único de forma multicomponente y libre de metales.