Departament de Química: Envíos recientes
Mostrando ítems 61-80 de 158
Oxidation of unactivated C-H bonds catalyzed by manganese complexes: control over site-selectivity and enantioselectivity
The oxidation of aliphatic C-H bonds is a very powerful reaction because it allows the functionalization of inert C-H bonds, converting them into a suitable sites for further chemical elaboration. It also represents one ...
Gold complexes for homogeneous cross-coupling catalysis and migratory insertion reactions
Most of the different homogeneous reactions catalyzed by gold have been developed in the past fifteen years and stem from the ability of both Au(I) and Au(III) complexes to coordinate and activate multiple carbon-carbon ...
Reduced density matrices: development and chemical applications
In this thesis, we focused on the alternative methodologies that are based on the reconstruction of density matrices. While in DFT several benchmarks can be found in the literature, for the rest of alternative methodologies ...
Computational chemistry applied to hydrocarbon functionalization by iron catalysts, oxidation state characterization, and electrides design
In this thesis, the three constituent areas of chemistry (in agreement with Jensen's quotation in his "Introduction to Computational Chemistry" book), which are construction, transformation, and properties of molecules, ...
Computational study of nuclear magnetic shielding constants
Nuclear Magnetic Resonance (NMR) spectroscopy is an indispensable structural tool in the modern analytical arsenal of chemists and structural biologists. The present thesis is a computational study of the NMR shift constants ...
Electronic structure, chemical bonding, and electronic delocalization of organic and inorganic systems with three-dimensional or excited state aromaticity
Aromaticity is a key concept in chemistry, used by chemists to explain the structure, stability, and reactivity of many compounds. Aromatic compounds are present in industrial processes as well as in living systems. ...
Rhodium-catalysed [2+2+2] cycloaddition reactions for the preparation of highly functionalised cyclic compounds
Transition metal-catalysed [2+2+2] cycloaddition reactions involving unsaturated substrates represent one of the most elegant methods in organic chemistry to prepare functionalised cyclic compound. This doctoral thesis is ...
Cobalt-catalyzed C-H functionalization: from mechanistic studies to synthetic methodologies
This Ph.D. dissertation describes the synthesis and characterization of bench-top stable aryl-Co(III) organometallic species using commercially available cobalt(II) salts and a macrocyclic model substrate. Special attention ...
High-valent iron complexes supported with tetradentate and pentadentate ligands based on the triazacyclononane scaffold
In this work we have prepared octahedral non - heme iron species in high oxidation states. Iron (IV) - oxo and iron (IV) - imido complexes based on triazacyclononane scaffold had been synthesised and all of them had been ...
Nous formats en la comunicació de la química. Explorant el seu paper en el foment de la cultura i les vocacions científiques
Throughout this thesis I was involved in different science communication projects where research and innovation have been applied to improve existing proposals and exploring new formats without forget the evaluation of the ...
Assessment of wastewater phytotechnologies for the attenuation of emerging organic contaminants and development of innovative analytical methods for their determination
Emerging organic contaminants (EOCs), like pharmaceuticals and endocrine disrupting compounds, are continuously introduced into the environment. Some 2/2 have been found in water bodies, posing a risk on human health and ...
Reaction mechanisms involved in cross coupling processes catalysed by copper and nickel
Organometallic aryl-CuIII species have been proposed as key intermediates in Ullmann-type reactions. However, such species have long remained elusive and mechanistic investigations of a plausible catalytic cycle remained ...
New carbocyclisations of polyunsaturated hydrazones catalysed by rhodium(I)
Some of the most powerful methods for synthesizing complex organic molecules with high levels of chemo-, diastereo- and enantioselectivity rely on metal carbene chemistry. These compounds are versatile reaction intermediates ...
Understanding C-H oxidation and amination reactions performed by late first-row transition metals: trapping high-valent metal-O/N species
The transformation of C-H bonds into C-O/N bonds is a process of interest in organic synthesis, but controlling the reactivity and selectivity among the multiple C-H bonds existing in most molecules is a challenging task. ...
Analysis of chemotherapy drugs and related compounds in aquatic environment: removal, transformation and risk evaluation in eco-friendly and advanced technologies
In order to evaluate the increasing environmental and human risk of anticancer drugs in the environment, more information needs to be gathered about their presence, their toxicity, bioaccumulation and persistence. In ...
Reactivity of fullerenes, endohedral metallofullerenes, and nanotubes, and their possible application in solar energy conversion
The physical and chemical properties of fullerenes and nanotubes can be conveniently tuned by the attachment of different functional groups to them. Therefore, the systematic understanding of different problems such as ...
Bioinspired copper and nonheme iron models for oxygen activation: unprecedented reactivities
The oxidation of hydrocarbons is one of the most important processes in the chemical industry, and it is often related to highly toxic reagents that generate a big amount of undesired residues. In sharp contrast, oxygenase ...
Theoretical study of water oxidation and reduction mechanisms by aminopyridine first row transition metal catalysts
One of the major current scientific goals is the development of renewable energy sources. An effective alternative to fossil fuels consists in the conversion of the sunlight energy into chemical fuels. The molecular hydrogen ...
Solid-phase synthesis of cell-penetrating γ-peptide/antimicrobial peptide conjugates and of cyclic lipodepsipeptides derived from fengycins
This thesis is focused on the development of synthetic approaches to obtain new bioactive peptides. The first part deals with the design of new antimicrobial peptide/cell-penetrating peptide conjugates as anticancer agents. ...
Solid-phase synthesis of 5-arylhistidine-containing peptides: from linear antimicrobial peptides to cyclic peptides derived from arylomycins and aciculitins
The incorporation of unsymmetrical biaryl systems into peptide sequences is a strategy that can improve their biological activity. Due to the difficulty of arylating the 4(5}-position of the imidazole ring, this doctoral ...
