Síntesi i caracterització de curcuminoïdes i sistemes polimerics derivats
- Autores: Laura Rodríguez Cid
- Directores de la Tesis: María Concepción Domingo Pascual (dir. tes.), Núria Aliaga-Alcalde (codir. tes.)
- Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2021
- Idioma: catalán
- Tribunal Calificador de la Tesis: María Rosa Aguilar de Armas (presid.), Mónica Giménez Marqués (secret.), Silvia Gómez-Coca (voc.)
- Programa de doctorado: Programa de Doctorado en Química por la Universidad Autónoma de Barcelona
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
Curcuminoids (CCMoids) are a group of molecules that display two aromatic rings joined by a seven-carbon conjugated chain (diarylheptanoids) and a β-diketone moiety in the central position of their structures. The straightforward synthesis of this type of molecules allows their thorough design depending on the final purpose, mainly by modifying the lateral substituents, but also the chain length and/or the β-diketone unit. Despite of the number of CCMoids that have been synthetized until now, and the presence in many of them of functional groups susceptible to react with other species, the use of CCMoids as building blocks for the creation of highly dimensional structures is scarce. This, together with the properties shown by this family of molecules (biomedical, electronic…) and their versatile chemistry, motivated the development of the ideas presented in this doctoral thesis.
In this sense, nine CCMoids, including four not previously described in the literature, are presented in this doctoral thesis. Moreover, their detailed characterization has been carried out, probing not only the achieving of the desired molecules in high purity but also how their structural differences may affect their physicochemical properties. Regarding the formation of extended structures, several coordination polymers (CPs) have been achieved from the reaction with transition metal ions and first steps in the synthesis of organic polymers (OPs) are also shown.
For the studies of CPs, two CCMoids were tested: a natural one, the bisdemethoxycurcumin (BDMC), with phenol groups at the sites of the molecule, and a synthetic CCMoid, 3pyCCMoid, with pyridines as aromatic substituents.
The reaction between BDMC and zinc acetate, performed under mild conditions in EtOH, provides a new 1D system. In addition, dimensionality and porosity of this network have been expanded by studying the reaction occurring between three species: BDMC, Zn(II) salts, and a ditopic co-linker (1,2-bis(4-pyridyl)ethylene, 1,3-bis(4-pyridyl)propane or 4,4′-bipyridine). In total, here seven new CPs are presented. The structures of five of them were elucidated by single-crystal X-ray diffraction. Moreover, we show that the combination of solid state 13C NMR and conventional techniques (elemental analysis, FTIR.) can provide useful information about the coordination modes of BDMC, in the cases of unresolved structures.
The coordination of 3pyCCMoid with Zn(II) centres results in three CPs with different architectures and dimensionalities (from 1D to 3D). Here it is examined how synthetic methods and some slightly changes, in the reaction conditions, affect the formation of the final materials. In addition, an effective method for the exfoliation of a 2D CP was optimized and the characterization of the few layer nanosheets performed. Using the same CCMoid but reacting with a Co(II) salt, an isostructural 2D CP was synthetized, being the first CCMoid-CP with a metal different than Zn(II).
For the synthesis of OPs, two approaches have been proposed: (i) the formation of extended structures by the use of a CCMoid with boronic acids (BOHCCMoidBF2) at the sites that reacts with commercial polyols and, (ii) the in-situ synthesis of CCMoid units that evolve together forming high dimensional materials. Regarding this part, preliminary results are presented in this Thesis, proving the formation of expanded structures, and encouraging future work to continue with this study.
Here, the variety of structures, different dimensionalities and conformations adopted by the studied CCMoids probe the potential of these molecules to form extended structures by themselves or with the assistance of metal coordination and/or co-linkers.
