Tesi di Dottorato
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Item Sintesi e caratterizzazione di materiali bioattivi e/o cromonici a base di complessi di metalli di transizione(2014-12-12) Sanz Mendiguchia, Barbara; Bartolino, Roberto; Crispini, AlessandraItem Theoretical investigation of the enzyme promiscuity within the carbonic anhydrase's family(2014-11-28) Piazzetta, Paolo; Bartolino, Roberto; Marino, PaoloItem Studio Teorico dei Dettagli Meccanicistici di Reazioni Organiche Catalizzate da Oro(2014-03-31) Mazzone, Gloria; Russo, Nino; Sicilia, EmiliaThe catalytic chemistry of gold has had a relatively belated development with respect to other late transition metals, and this has been attributed to the preconception that gold is expensive and unreactive. The interest in gold has grown over the last thirty years, because both of these conceptions have been proven false, and successful applications of gold catalysis have emerged in chemical processing, pollution control, fuel cells design, and many others fields. These evidences have sparked a veritable “gold rush” in the field of catalysis, both homogeneous and heterogeneous. We investigated the role of gold in both homogeneous and heterogeneous catalytic processes. In fact, the theoretical study of mechanistic details for reactions, that involves and underline the characteristics of gold, have been the subjects of this thesis. Density functional theory (DFT) is the method of choice in this kind of studies. Regarding heterogeneous catalysis the synthesis of vinylacetate is the reaction on which we have focused our attention. In particular, a bimetallic catalyst containing low Pd coverage on Au surface (100 and 111) has been selected to outline the reaction mechanism of VAM formation. We have studied in detail both mechanisms proposed in literature, in order to selected the more active surface and the more likely mechanism. The homogeneous catalytic process that has been selected to point out the catalytic activity of gold is the hydration of 1,2-diphenylacetylene to yield benzyl phenyl ketone, catalyzed by a complex of Au(I) with triphenylposphine. This cationic complex coordinates to the alkyne in the first step of the catalytic cycle, thus rendering it more susceptible for a nucleophilic attack. That reaction is a relatively new synthetic strategy that have recently studied experimentally. Our aim is to elucidate the mechanism of the whole reaction.Item Spettri elettronici di molecole di interesse farmacologico nella terapia fotodinamica(2014-03-28) Quartarolo, Angelo; Russo, NinoItem Investigazione teorica delle proprietà delle unità strutturali presenti negli acidi nucleici e delle interazioni di queste con ioni metallici e molecole di acqua(2014-03-28) Mazzuca, Donatella; Russo, Nino; Toscano, MarirosaItem Complessi Fotoattivi di Palladio e Platino. Processi di Ciclometallazione, Studio delle Caratteristiche Elettroniche e delle Proprietà di Interesse Applicativo(2014-03-28) Pugliese, Teresa; Russo, Nino; Pucci, DanielaItem Determinadi meccanismi di reazioni catalizzate da metallo-enzimi(2014-03-27) Amata, Orazio; Russo, Nino; Toscano, MarirosaItem Studio teorico dell'attivazione dei legami C-H e C-C mediante cationi di attinidi in fase gassosa(2014-03-27) Di Santo, Emanuela; Russo, Nino; Michelini, Maria del CarmenDensity functional theory calculations were performed to study the ability of thorium (Th+, Th2+) and uranium (U+, U2+ The potential energy surfaces were explored taking into consideration different spin states. A close description of the reaction pathways leading to different reaction products is presented, and the obtained results are compared with experimental data. ) cations to activate the C-H and C-C bonds of methane, ethane and propane in the gas-phase. Th+ activates the C-H bonds of methane and ethane, in contrast, U+ is inert in both reactions. Th2+ reacts with all three alkanes, whereas U2+ reacts with C2H6 and C3H8, with product distributions different than those of Th2+ The computed potential energy profiles, which all proceed by insertion, were used to evaluate the relationship between the energetics of the bare Th . + (2+) and U+ (2+) ions and the energies for C-H and C-C bond activation. It was found that the computed energetics for insertion are entirely consistent with the empirical model which relates insertion efficiency to the energy needed to promote the An+ (2+) ion from its ground state to a prepared divalent state with two non 5f valence electrons suitable for bond formation in {C-An+ (2+)-H} and {C-An+ (2+)-C} activated intermediates.Item Complessi eterolettici di Zn(II), Eu(III) e Tb(III)(2014-03-27) Liguori, Paola F.; Russo, Nino; Pucci, DanielaItem Sintesi e studio di nuovi complessi contenenti Zn(II) e Pd(II) con potenziali proprietà elettroottiche(2014-03-26) Spataro, Tania; Versace, Carlo; Aiello, Iolinda