Catalytic systems adapted to glycerol medium. Applications in selective processes

Resumen

con otros disolventes (incluyendo próticos), probablemente por su habilidad para formar enlaces de hidrógeno, lo que favorece la interacción con la radiación de microondas acelerando el proceso. Con el objetivo de estudiar procesos estereoselectivos en este medio, hemos sintetizado por primera vez nuevos derivados de PTA (1,3,5-triaza-7- fosfaadamantano) enantiopuros y hemos estudiado su actividad en diferentes reacciones catalíticas asimétricas de interés. Solvents are needed in large scale for different industrial applications. The search for less harmful, biodegradable, non-toxic green alternatives able to replace conventional organic solvents is an active area of research, especially when these solvents can be reused without the need of reconditioning treatments. In this sense, solvents derived from biomass are emerging as very promising solutions. Glycerol, produced in high amounts as a side product in biodiesel production, represents a good candidate. Due to its low cost, low toxicity, high boiling point and selective solubility and miscibility with organic compounds, glycerol represents a good choice to be applied in chemical transformations, including catalytic ones. This Thesis deals with the development of new catalytic systems in glycerol medium. In particular, in this work we show how glycerol can facilitate the stabilization of copper(I) nanoparticles that are able to catalyze the 1,3-dipolar Huisgen cycloaddition between terminal alkynes and organic azides (known as click reaction). Moreover, this reaction can be carried out in the absence of copper using internal alkynes, working under microwave irradiation. Glycerol favours the process in comparison with other solvents (including protic ones), probably due to its ability to form hydrogen bonds, which favors the interaction with microwave irradiation (accelerating the process).