Selective Oxidation of Glycerol via Acceptorless Dehydrogenation Driven by Ir(I)-NHC Catalysts

After pandemic, healthcare workers experienced a series of emotional and psychological disturbances that could impact their mental well-being. In this study, the feasibility of morphological characteristics of photoplethysmographic (PPG) waveform to quantify stress and depression level posed by COVID-19 in first-line healthcare workers is explored. Results show that higher stress and depression level are moderately correlated with large systolic amplitude and parameters that might indicate early wave reflection. These results suggest that an arterial stiffness, quantified with PPG morphological characteristics, could provide valuable information in assessing mental healt

Acceptorless dehydrogenation of alcohols to carboxylic acids by Ir-NHC catalysts

Resumen del póster presentado a la 24th Virtual Conference on Organometallic Chemistry (EuCOMC XXIV Virtual Conference), celebrada del 1 al 3 de septiembre de 2021.Peer reviewe

Design of Ir-NHC catalysts for acceptorless dehydrogenation of alcohols to carboxylic acids

Póster presentado al Symposium of the Spanish Royal Society of Chemistry, celebrado on-line del 27 al 30 de septiembre de 2021.Peer reviewe

Design of Ir-NHC catalysts for acceptorless dehydrogenation processes

Resumen del póster presentado a la XXXVIII Reunión Bienal de la Real Sociedad Española de Química, celebrada en el Palacio de Congresos de Granada, del 27 de junio al 30 de junio de 2022.The transition from traditional carbon-based energy systems into more sustainable and renewable ones is a crucial subject matter nowadays. In this regard, molecular hydrogen arises as one of the main and most efficient energy vectors as its reaction with oxygen provides energy and only generates water as a by-product. The difficulties in its storage and transport can be overcome with Liquid Organic Hydrogen Carriers (LOHC), organic substances that store hydrogen through catalytic hydrogenation and dehydrogenation processes over multiple cycles and may support a future hydrogen economy. In this sense formic acid is considered as one of the most promising LOHC. Dehydrogenation reactions play also a key role in the valorization of readily available and inexpensive bulk chemicals such as glycerol, or in the production of fine chemicals like carbonyl and carboxylic compounds from primary and secondary alcohols. Interestingly, under acceptorless conditions dehydrogenation reactions generate valuable molecular hydrogen as by-product, making the processes more competitive from an economic point of view. Within this context, Ir-NHC compounds have been stablished as leading catalysts in the dehydrogenation processes of a wide range of substrates. In the present work, we depict the synthesis of different Ir(I) and Ir(III) complexes bearing asymmetric NHC ligands with a pyridyl fragment and a rigid oxygen-donor moiety in its structure. These compounds have shown to be efficient catalysts for the dehydrogenation of several substrates such as glycerol, benzyl alcohol derivatives and formic acid [Scheme 1: acceptorless dehydrogenation reactions catalyzed by Ir-NHC complexes]. The coordination mode of the ligands plays an essential role in the dehydrogenation processes, resulting in marked differences in catalytic activity.Peer reviewe

Deshidrogenación de alcoholes primarios a ácidos carboxílicos en ausencia de aceptor de hidrógeno por catalizadores Ir-NHC

Resumen del póster presentado a la 9ª Jornada de Jóvenes Investigadores de Química y Física de Aragón, celebrada el 16 de diciembre de 2021 en la Universidad de Zaragoza.Peer reviewe

Selective Oxidation of Glycerol via Acceptorless Dehydrogenation Driven by Ir(I)-NHC Catalysts

Iridium(I) compounds featuring bridge-functionalized bis-NHC ligands (NHC = N-heterocyclic carbene), [Ir(cod)(bis-NHC)] and [Ir(CO)2(bis-NHC)], have been prepared from the appropriate carboxylate- or hydroxy-functionalized bis-imidazolium salts. The related complexes [Ir(cod)(NHC)2]+ and [IrCl(cod)(NHC)(cod)] have been synthesized from a 3-hydroxypropyl functionalized imidazolium salt. These complexes have been shown to be robust catalysts in the oxidative dehydrogenation of glycerol to lactate (LA) with dihydrogen release. High activity and selectivity to LA were achieved in an open system under low catalyst loadings using KOH as a base. The hydroxy-functionalized bis-NHC catalysts are much more active than both the carboxylate-functionalized ones and the unbridged bis-NHC iridium(I) catalyst with hydroxyalkyl-functionalized NHC ligands. In general, carbonyl complexes are more active than the related 1,5-cyclooctadiene ones. The catalyst [Ir(CO)2{(MeImCH2)2CHOH}]Br exhibits the highest productivity affording TONs to LA up to 15,000 at very low catalyst loadings

Un mar de aire

Contiene: Cuaderno del profesor y cuadernos del alumnoUnidad didáctica que propone al alumnado del primer ciclo de educación primaria propuestas de actividades sobre educación ambiental destinadas a dar ideas al alumnado, crearles problemas y conflictos, sugerirles preguntas y respuestas destinadas a que el alumnado trabaje el concepto de aire.ValenciaBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín, 5; 28014 Madrid; Tel. +34917748000; [email protected]

Estudio, gestión, conservación y restauración de ecosistemas ante el cambio global: 1° Jornadas FORECO en la Universidad de Alcalá

La conservación y la restauración del capital natural es una necesidad apremiante en el escenario de cambio global que estamos viviendo, en donde se están intensificando los impactos sobre los ecosistemas. En este contexto, el Grupo de Ecología Forestal y Restauración de la Universidad de Alcalá (>Forest Ecology and Restoration Group” FORECO (Fig.1)) ha surgido precisamente para generar el conocimiento científico necesario para afrontar los nuevos retos de gestión, conservación y restauración de los ecosistemas.Peer Reviewe