The use of thermally activated delayed fluorescence (TADF) emitters in light-mediated strain-release processes

In my thesis, I have investigated the development of new purely organic photocatalysts designed to catalyze a synthetic organic transformation. In particular I focused on a new strain-release driven process mediated by visible-light. Here, a new class of thermally activated delayed fluorescence (TADF) emitters, commonly used in organic light-emitted diodes (OLEDs) manufacturing, were employed. To the best of our knowledge, these molecules were used as photosensitizers in an energy-transfer manifold for the very first time. The transformation under study proceeds through the sensitization of sulfonylimines, that subsequently react with a strained heterocycle, leading to a family of di-functionalizaed azetidines, relevant scaffolds in drug discovery platforms. The research was divided in two main phases, an initial optimisation phase that required the identification and optimization of key reaction parameters such as light source, catalyst nature and loading, and reaction conditions to achieve the highest yield and selectivity, followed by an applicative phase, which consisted on the full characterization of the resulting new compounds and the mechanistic investigations of the process.