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The functionalization of an imine-based layered covalent organic framework (COF), containing phenanthroline units as ligands, has allowed the obtention of a heterobimetallated material. Photoactive Ir and Ni fragments were immobilized within the porous structure of the COF, enabling heterogeneous light-mediated Csp 3 -Csp 2 cross-couplings. As radical precursors, potassium benzyl- and alkoxy-trifluoroborates, organic silicates, and proline derivatives were employed, which brings out the good versatility of Ir,Ni@Phen-COF. Moreover, in all the studied cases, an enhanced activity and stability have been observed in comparison with analogous homogenous systems.

Descripció del recurs: el 19-08-2008, Consultable des del TDX, Títol obtingut de la portada digitalitzada, El trabajo experimental ha desarrollado tres objetivos que se enmarcan dentro del campo de la química de coordinación del platino(II) con ligandos que contienen azufre y de sus posibles aplicaciones. Así, primero se ha profundizado en el estudio de la influencia de los ligandos terminales en la reactividad del anillo central {Pt2S2} en complejos de fórmula [Pt2L2(μ-S)2] frente a un amplio conjunto de especies electrófilas. Posteriormente, se ha explorado la reactividad del complejo [Pt2(dppp)2H3]ClO4 (dppp = Ph2P(CH2)3PPh2) en presencia de aniones sulfuro o hidrogenosulfuro bajo diferentes condiciones experimentales. Y, finalmente, se ha estudiado la reacción de dicho complejo binuclear de platino con tiofeno, reacción que se puede considerar adecuada para modelar el proceso industrial de hidrodesulfuración del petroleo, es decir, la liberación de azufre de los compuestos organosulfurados que contiene. Todos estos objetivos se han conseguido mediante la utilización de técnicas avanzadas de resolución estructural directa, RMN y espectrometría de masas, las cuales han permitido la caracterización de un elevado número de nuevos compuestos, así como el estudio de su reactividad. Además, medidas electroquímicas y cálculos computacionales (DFT) han enriquecido la caracterización de los complejos obtenidos y han permitido proponer el mecanismo que acompaña su formación. El primer objetivo se ha desarrollado mediante: a) la síntesis y caracterización estructural de [Pt2(Ph2X(CH2)2XPh2)2(µ-S)2] (X = As), b) determinación de sus propiedades redox, y c) estudio de la nucleofilicidad de los átomos de azufre respecto a diversos centros metálicos, ácidos próticos (HCl, HClO4) y electrófilos orgánicos (CH2Cl2). La comparación de estos resultados con los anteriormente obtenidos para X = P ha permitido concluir que el cambio de átomo donador X en los ligandos terminales del anillo central {Pt2S2} no implica cambios estructurales notables entre complejos análogos, pero en cambio X =, The experimental work has aimed at three objectives, all embodied in the field of the coordination chemistry of Pt(II) with sulfur-containing ligands and their possible applications. Thus, firstly, the influence of the terminal ligands in the reactivity of the central {Pt2S2} ring in complexes of formula [Pt2L2(μ-S)2] towards a wide collection of electrophilic species has been thoroughly studied. Subsequently, the reactivity of the complex [Pt2(dppp)2H3]ClO4 (dppp = Ph2P(CH2)3PPh2) in the presence of sulfide or hydrogensulfide anions has been explored under various experimental conditions. And finally, the reaction of the upper binuclear platinum complex with thiophene has been analyzed in detail. This reaction can be considered as a good model for the industrial process of hydrodesulfurization of petroleum, which involves the removal of sulfur from the included organosulfur compounds. All of these objectives have been achieved using advanced techniques of direct structural resolution, NMR and mass spectrometry, which have allowed the characterization of a high number of new complexes, as well as the study of its reactivity. In addition, electrochemistry measurements and in silico studies (DFT) have enriched the characterization of the complexes obtained and they have also allowed us to propose the reaction mechanism that accompanies their formation. The first objective has been developed through: a) the synthesis and structural characterization of [Pt2(Ph2X(CH2)2XPh2)2(µ-S)2] (X = As), b) the determination of its redox properties, and c) the study of the nucleophilicity of the sulfur atoms towards various metal centres, protic acids (HCl, HClO4) and organic electrophiles (CH2Cl2). Comparison of these results with those previously obtained for X = P have allowed us to conclude that the replacement of the donor atom X in the terminal ligands bound to the {Pt2S2} core does not involve significant structural changes in analogue complexes. However, when X = As the elect