Light-Mediated Organocatalysis with N-Heterocyclic Carbenes

• Applicant: Professorin Dr. Beate Koksch, since 10/2021
• Subject Area: Organic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2019 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 420535461

This project is focused on investigating the effect of light irradiation on organic reactions catalysed by N-heterocyclic carbenes (NHCs). NHC-Organocatalysis has emerged as a powerful tool that facilitates many synthetically important and often enantioselective transformations including umpolung reactions of aldehyde derivatives. Despite the great advances made in recent years, the range of accessible reaction pathways remains largely limited to classical aldol-type processes and new strategies involving different, non-classical pathways that enhance the scope of this chemistry are highly sought. Inspired by the previously-noted ability of NHCs to stabilise open-shell species, we intend to study the effect of light irradiation on NHC-catalyzed reactions of carbonyl compounds, focusing mostly on carboxylic acid and ester substrates. The project concerns a new catalysis concept involving light-mediated excitation of acyl azolium intermediates that allows classical photochemical reactions conventionally performed on ketones to be conducted using previously unsuitable carboxylic acid derivative substrates. New catalytic applications of this concept will be developed while stoichiometric studies including spectroscopic and experimental investigations will be used to provide mechanistic insight and guide reaction development.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr. Matthew Hopkinson, until 9/2021