Diseño de una secuencia didáctica para la comprensión lectora en textos narrativos (cuentos policíacos) en estudiantes de grado sexto de educación básica secundaria EBS

El propósito de esta investigación es diseñar una secuencia didáctica para fortalecer los procesos de comprensión lectora en estudiantes de grado sexto de educación básica secundaria; implementando como estrategia de enseñanza y aprendizaje el modelo interactivo desde la perspectiva teórica de Isabel Solé. La secuencia didáctica permitirá desarrollar y fortalecer las habilidades de lectura en los estudiantes, por medio de la narrativa del cuento policíaco de Edgar Allan Poe. Para desarrollar esta propuesta investigativa se tomaron los aportes desde las teorías de Camps en lo referido a la secuencia didáctica, Lerner y su preocupación por la enseñanza de la lectura y la escritura en la escuela, Cortés y Bautista del texto narrativo y en especial el texto de Edgar Allan Poe de género policiaco, el cual inspiró la realización de la secuencia e iincitarán al estudiante a descubrir el amor por la literatura

Titanocene-promoted stereoselective eliminations on epoxy alcohols derived from R-(−)-carvone

[EN]The reaction of several stereoisomeric epoxy alcohols, obtained from R-(−)-carvone, and their corresponding formates, acetates, and benzoates, promoted by Cp2TiCl has been studied. The different outcomes of the reaction of epoxy derivatives are rationalized in terms of mechanistically biased processes. The radicals emerging from oxirane cleavage provide two types of reaction: dehydroxylation (deoxycarbonylation) and dehydrogenation. The results offer considerable support for the radical elimination theory of hydroxyl, formyloxyl, and acetoxyl groups. The inability of tertiary radicals to be reduced by the Ti(III) complex is demonstrated unequivocally

Radical reactions on pinene-oxide derivatives induced by Ti(III)

[EN]A practical, brief and selective synthesis of several pinene oxide derived terpenoids can be achieved from readily available starting materials. The key step is a radical reaction promoted by titanocene chloride

Implantació d'un EMAS a la UPC

La present ponència s’emmarca dins de les iniciatives “motor de canvi” que està portant a terme la Universitat Politècnica de Catalunya (UPC), dins del seu compromís amb la Sostenibilitat. Aquest projecte s’inclou dins del Pla UPC Sostenible 2015, i s’està realitzant actualment en el Campus del Baix Llobregat i en el Campus de Manresa, com a prova pilot. S’està desenvolupant un model de Sistema de Gestió Ambiental (SGA), en aquest cas basat en EMAS, adaptat a les organitzacions del coneixement (OdC). La innovació del projecte es basa en la inclusió de la part de recerca i docència d’una universitat dins un SGA-EMAS. El projecte vol demostrar-ne l’adaptabilitat i sobretot la replicabilitat a la resta d’OdC. L’objectiu és dissenyar un model teòric i assajar-lo en els campus amb diferents participants, per a mostrar l’abast de la seva efectivitat.Peer Reviewe

Radical reactions of epoxy esters induced by titanocene chloride

[EN]The reductive radical cyclizations of several epoxy esters have been achieved using titanocene chloride. The tether length from the initial radical to the carbonyl acceptor is the key of the reactions. We obtained products from radical cyclization onto carbonyl formate and products from formate and hydrogen elimination. The stereochemical outcome of the 5-exo radical cyclization of two diastereomers is reported. A radical cascade cyclization of an unsaturated epoxy formate is also described

Titanocene-Promoted Intermolecular Couplings of Epoxides with Nitriles. An Easy Access to β-Hydroxyketones

[EN]Radical couplings of epoxides and nitriles mediated by Cp2TiCl provide a diastereoselective route to the synthesis of β-hydroxyketones. The conditions of this “aldol-like” reaction are mild enough to avoid the dehydration of the β-hydroxyketone. The scope of the coupling reaction with functionalized and tetrasubstituted epoxides has been studied. The radical character of the coupling reactions is demonstrated

Radical Titanocene Promoted Coupling of Epoxides and Vinyl Sulfones

[EN]A radical coupling reaction of diverse vinyl sulfones and epoxides was mediated by Cp2TiCl (Cp = cyclopentadienyl) to provide a straightforward synthetic pathway to hydroxy sulfones. The reaction was successfully achieved by using either an excess or a catalytic amount of the TiIII reagent. The scope of the reaction was studied for several different functionalized and substituted epoxides and vinyl sulfones

Radical Cyclization of Epoxy Vinyl- and Allylsulfones Promoted by Titanocene Chloride

[EN]A titanocene-mediated intramolecular radical addition of different epoxy vinyl- and allylsulfones has been achieved. Five- and six-membered ring products were obtained in good to excellent yields in the presence of both 2.2 and 0.2 equiv of Cp2TiCl. A novel double-activation strategy allowed us to achieve small-size rings such as cyclobutanes and cyclopropanes

Titanocene‐Promoted Eliminations on Epoxy Alcohols and Epoxy Esters

[EN]The reaction of a series of 2,3-epoxy alcohols and the corresponding formates, acetates, and benzoates promoted by Cp2TiCl has been studied. The different outcome of the reaction of epoxy derivatives has been rationalized in terms of mechanistically biased processes. After homolytic oxirane cleavage, four main types of reaction were found: dehydroxylation, decarboxylation, dehydrogenation, and deoxygenation. The reaction products varied according to the substitution pattern. The radical nature of these eliminations is demonstrated

Synthesis of limonoid CDE fragments related to limonin and nimbinim

[EN]A practical, brief and selective synthesis of limonoid CDE fragments from a readily available starting diketone is described. The key step is a cationic electrocyclization promoted by strong acids. In general the methodology has been demonstrated for compounds with sensitive furane and thiophene substituents to obtain diverse substituted indenones. Several of the compounds obtained show significant antifeedant activity against Spodoptera littoralis