Nature of the Hydrogen Bond Enhanced Halogen Bond

The factors responsible for the enhancement of the halogen bond by an adjacent hydrogen bond have been quantitatively explored by means of state-of-the-art computational methods. It is found that the strength of a halogen bond is enhanced by ca. 3 kcal/mol when the halogen donor simultaneously operates as a halogen bond donor and a hydrogen bond acceptor. This enhancement is the result of both stronger electrostatic and orbital interactions between the XB donor and the XB acceptor, which indicates a significant degree of covalency in these halogen bonds. In addition, the halogen bond strength can be easily tuned by modifying the electron density of the aryl group of the XB donor as well as the acidity of the hydrogen atoms responsible for the hydrogen bond.Depto. de Química OrgánicaFac. de Ciencias QuímicasTRUEMINECO and MICIINpu

Automatic learning framework for pharmaceutical record matching

Pharmaceutical manufacturers need to analyse a vast number of products in their daily activities. Many times, the same product can be registered several times by different systems using different attributes, and these companies require accurate and quality information regarding their products since these products are drugs. The central hypothesis of this research work is that machine learning can be applied to this domain to efficiently merge different data sources and match the records related to the same product. No human is able to do this in a reasonable way because the number of records to be matched is extremely high. This article presents a framework for pharmaceutical record matching based on machine learning techniques in a big data environment. The proposed framework aims to explode the well-known rules for the matching of records from different databases for training machine learning models. Then the trained models are evaluated by predicting matches with records that do not follow these known rules. Finally, the production environment is simulated by generating a huge amount of combinations of records and predicting the matches. The obtained results show that, despite the good results obtained with the training datasets, in the production environment, the average accuracy of the best model is around 85%. That shows that matches which do not follow the known rules can be predicted and, considering that there is not a human way to process this amount of data, the results are promising.This work was supported by the Research Program of the Ministry of Economy and competitiveness, Government of Spain, through the DeepEMR Project, under Grant TIN2017-87548-C2-1-

Magnetic Surfaces in Stationary Axisymmetric General Relativity

In this paper a new method is derived for constructing electromagnetic surface sources for stationary axisymmetric electrovac spacetimes endowed with non-smooth or even discontinuous Ernst potentials. This can be viewed as a generalization of some classical potential theory results, since lack of continuity of the potential is related to dipole density and lack of smoothness, to monopole density. In particular this approach is useful for constructing the dipole source for the magnetic field. This formalism involves solving a linear elliptic differential equation with boundary conditions at infinity. As an example, two different models of surface densities for the Kerr-Newman electrovac spacetime are derived.Comment: 15 page

La incorporación de la voz del alumnado en el desarrollo de una estructura curricular modular. La experiencia del grado de educación social en la UPV-EHU

Con el objetivo de acercar las prácticas universitarias al discurso de democratización educativa, este artículo recoge la experiencia de la incorporación de la voz del alumnado en el desarrollo de la estructura modular del Grado de Educación Social de la UPV-EHU. Centrándonos en un análisis del efecto de la incorporación de la voz del alumnado en las estructuras organizativas, en diferentes contextos, en su propio aprendizaje y en el cambio de las prácticas docentes, hemos intentado desvelar el sentido otorgado a la participación del alumnado en la vida formativa y universitaria, detectar los claroscuros que se visualizan a su acción como sujeto y analizar el efecto producido en su aprendizaje.With the aim of bringing university practices to address educational democratization, this article describes the experiences of incorporating student voice in the development of the modular structure of Social Education degree from the UPV-EHU. Focusing on an analysis of the effect of the incorporation of student voice in organizational structures, in different contexts, in their own learning and changing teaching practices, we tried to reveal the meaning given to student participation in the life training and university detect shades that are displayed to its action as a subject and analyze the effect on their learning

Bonding Situation of σ‐E−H Complexes in Transition Metal and Main Group Compounds

The ambiguous bonding situation of σ-E−H (E=Si, B) complexes in transition metal compounds has been rationalized by means of Density Functional Theory calculations. To this end, the combination of the Energy Decomposition Analysis (EDA) method and its Natural Orbital for Chemical Valance (NOCV) extension has been applied to representative complexes described in the literature where the possible η1 versus η2 coordination mode is not unambiguously defined. Our quantitative analyses, which complement previous data based on the application of the Quantum Theory of Atoms in Molecules (QTAIM) approach, indicate that there exists a continuum between genuine η1 and η2 modes depending mainly on the strength of the backdonation. Finally, we also applied this EDA-NOCV approach to related main-group species where the backdonation is minimal

Factors Controlling the Aluminum(I)‐ meta ‐Selective C−H Activation in Arenes

The so far poorly understood factors controlling the complete meta-selectivity observed in the C H activation reactions of alkylarenes promoted by aluminyl anions have been explored in detail by means of Density Functional Theory calculations. To this end, a combination of state-ofthe-art computational methods, namely the activation strain model of reactivity and energy decomposition analysis, has been applied to quantitatively unveil the origin of the selectivity of the transformation as well as the influence of the associated potassium cation. It is found that the selectivity takes place during the initial nucleophilic addition step where the key LP(Al)!π*(C=C) molecular orbital interaction is more stabilizing for the meta-pathway, which results in a stronger interaction between the reactants along the entire transformation

Highly Enantioselective Cobalt‐Catalyzed (3+2) Cycloadditions of Alkynylidenecyclopropanes

This is the peer reviewed version of the following article: E. Da Concepción, I. Fernández, J. L. Mascareñas, F. López, Angew. Chem. Int. Ed. 2021, 60, 8182, which has been published in final form at https://doi.org/10.1002/anie.202015202. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived VersionsLow‐valent cobalt complexes equipped with chiral ligands can efficiently promote highly enantioselective (3+2) cycloadditions of alkyne‐tethered alkylidenecyclopropanes. The annulation allows to assemble bicyclic systems containing five‐membered rings in good yields and with excellent enantiomeric ratios. We also present a mechanistic discussion based on experimental and computational data, which support the involvement of CoI/CoIII catalytic cyclesThis work received financial support from the Spanish MINECO (SAF2016‐76689‐R, CTQ2016‐78205‐P, CTQ2017‐84767‐P, PID2019‐106184GB‐I00 and PID2019‐108624RB‐I00), the Xunta de Galicia (ED431C 2017/19, 2015‐CP082, Centro Singular de Investigación de Galicia accreditation 2019–2022, ED431G 2019/03, and a predoctoral Fellowship to E. da C.) and the ERDF, ERC (Adv. Grant No. 340055)S

η 6 ‐Metalated Aryl Iodides in Diels‐Alder Cycloaddition Reactions: Mode of Activation and Catalysis

The potential application of η6-metalated aryl iodides as organocatalyst has been explored by means of computational methods. It is found that the enhanced halogen bonding donor ability of these species, in comparison with their demetalated counterparts, translates into a significant acceleration of the Diels-Alder cycloaddition reaction involving cyclohexadiene and methyl vinyl ketone. The factors behind this acceleration, the endo-exo selectivity of the process and the influence of the nature of the transition metal fragment in the activity of these species are quantitatively explored in detail by means of the combination of the Activation Strain Model of reaction and the Energy Decomposition Analysis methods

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Rhodium-Catalyzed Intramolecular [3+2+2] Cycloadditions between Alkylidenecyclopropanes, Alkynes, and Alkenes

A Rh-catalyzed intramolecular [3+2+2] cycloaddition is reported. The cycloaddition affords synthetically relevant 5,7,5-fused tricyclic systems of type 2 from readily available dienyne precursors. The transformation takes place with moderate or good yields, high diastereoselectivity, and total chemoselectivitySpanish MINECO. Grant Numbers: SAF2010-20822-C02-01/02, CTQ2010-20714-C02-01/BQU, CSD2007-00006 ERDF Xunta de Galicia. Grant Numbers: GRC2010/12, GR2013-041, INCITE09 209084PR, EM2013/036 European Research Council. Grant Number: 340055 CAM. Grant Number: S2009/PPQ-1634, AVANCATS