Aproximaciones a una Química más Sostenible: Inmovilización de Catalizadores en Polímeros y Catálisis Asimétrica en Sistemas Bifásicos Fluorados

Identificador:  TDX:2555

Handle: https://hdl.handle.net/20.500.11797/TDX2555

Autors:  Llanes Fernández, Patricia

Resum:
The project of the present doctoral thesis focuses in the development of new immobilized catalytic systems that allow to carry out different types of enantioselective reactions through processes with an improved sustainability profile. Consequently, organocatalysts immobilized on various solid supports as well as perfluorinated derivatives of homogeneous organocatalysts have been designed and prepared. In the first part of this thesis, the study and synthesis of a new family of ligands based on tris(triazolil)methanol (TTM) structures has been carried out. These ligands have been coordinated with CuCl, being optimal to catalyze cycloaddition reactions between alkynes and azides. In the case of the fluorinated systems, asymmetric catalysis has been carried with a homogeneous catalyst bearing a fluorinated chain. The recovery of these catalysts has been performed by a liquid–liquid extraction in a biphasic fluorous system (BFS). Concerning the solid phase, different types of organic supports based on polystyrene (commercial or home-made), emphasizing the understanding and control of the physical and chemical phenomena that determine and limit the useful life of the supported catalytic species. In particular, the effects on the catalytic properties of the matrix nature, the degree of cross–linker, the level of functionalization, and the nature of the functional unit required to anchor the catalyst onto the polymer. Regarding the preparation of the polymeric matrix, different strategies have been considered: a) polymeric support prepared by suspension copolymerization, b) tubular polymeric support structures known as monoliths. The ultimate objective of this thesis has been to develop continuous flow versions of various synthetic processes of interest using catalytic systems immobilized on new polymeric materials.