Ruthenium-Catalyzed Strategies for the Synthesis of Functional Molecules and Organic Receptors

Doctoral thesis, 2025

This thesis explores the development of ruthenium-catalyzed methodologies for the synthesis of functional molecules with potential applications in green chemistry, catalysis, and molecular recognition. The work presented aims at establishing new strategies for the construction of bio-based materials and 1,2,3-triazole-derived functional scaffolds, using ruthenium-catalyzed hydrogen transfer and azide-alkyne cycloaddition reactions (RuAAC).

The first part of this work demonstrates the potential of ruthenium catalysis in biomass valorization through the dimerization of vanillin derivatives into an epoxy divanillin ester (EDVE), a renewable precursor for polymer synthesis that may serve as a sustainable alternative to the reprotoxic bisphenol A molecule. Then, a sequential ruthenium-catalyzed azide–alkyne cycloaddition and hydrogen-borrowing strategy was developed, providing access to novel tricyclic 1,2,3-triazole-fused piperazines, architecturally complex heterocycles with potential catalytic or biological applications. The pyrrolidine-appended triazoles obtained as intermediates in this route were further investigated as organocatalysts in asymmetric aldol reactions employing green reaction conditions, illustrating how structural modifications within the triazole scaffold can influence reactivity and selectivity. Finally, 1,4,5-trisubstituted 1,2,3-triazole-based oligomers were constructed by combining ruthenium-catalyzed azide–alkyne cycloaddition for the modular synthesis of the triazole monomers with subsequent amide coupling to assemble linear and cyclic peptidotriazolamers. These structures were then evaluated for their ion recognition properties.

Altogether, the work presented in this thesis shows how the combination of Ru catalysis and molecular design can deliver new synthetic tools for renewable materials, asymmetric catalysis, and molecular sensing.