Multi-state chiroptical switches based on neutral homoaromatics

• Applicant: Professor Dr. Johannes F. Teichert
• Subject Area: Organic Molecular Chemistry - Synthesis and Characterisation
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 558033016

Chiroptical switches are molecules that upon irradiation can undergo a reversible structural change that alters at least one stereochemical element. These compounds are of fundamental interest for data storage on the molecular level. This research project aims at the synthesis of structurally new chiroptical switches and strategies to control the stereoselectivity of a photochemical sigmatropic rearrangement within one π system. The class of molecules that can address these research questions are homoaromatic homoannulenes. By controlling the directionality of the photochemical rearrangement, the homoannulenes become a structurally and conceptually new chiroptical switch, based on symmetry-breaking as a hitherto unexplored concept for stereoselective photochemical switching. This bears relevance for potential data storage on molecular level. The appropriate homoannulene photoswitches will be synthesized and three approaches to chiroptical switches to give diastereomeric and enantiomeric photoswitches are proposed.

• DFG Programme: Research Grants