From the Computer to the Lab: Rational Design and Synthesis of Light-Emitting Materials

Venecia

Congreso; Summer School for Sustainable Chemistry for Sustainable Development; 2023

In this report, we present a synthetic methodology of BiCz starting from diarylamines, in the presence of visible light and base at room temperature. We propose a novel iterative double cyclization intramolecular SRN1 as mechanism of the reaction. Through this technique, symmetric and unsymmetric BiCbz compounds were obtained in very good yields. The synthetic strategy employed was arylation of anilines, followed by an intramolecular SRN1 reaction, under mild conditions.Given the great variety of possible substituent combinations (R and R1), it is necessary to carry out a rational design to select the best candidates to synthesize. This step will be developed through molecular modeling. The selection of the R groups will be carried out from the energies of HOMO-LUMO molecular orbitals in the ground state using Density Functional Theory (DFT), and the energies of the excited states of S1 and T1 using time-dependent density functional theory (TD-DFT). The selection criterion will be based on the HOMO and LUMO being located in different areas of the molecule and the energies of the excited states of S1 and T1 being close to each other.Finally, the 3,3´-bicarbazoles obtained were characterized using spectroscopic techniques. The photophysical studies were developed mainly in solution using static and laser flash photolysis techniques, determining photophysical characteristics such as absorption and/or emission color and lifetimes of the excited states. Furthermore, fluorescence quantum yields were determined.