Research in the Theunissen Group

   The main focus of our research is the development of new chemical processes in organic synthesis based on the use of transition-metal catalysis, photoredox catalysis and electrochemistry. In particular, we have recently started a new research program on the generation of radical intermediates by activation of carbon – nitrogen bonds, traditionally considered as unreactive. Such transformations open exciting perspectives for the design of innovative processes from more sustainable starting materials such as amine derivatives.

   In this context, we have worked on the reductive activation of quaternary ammonium salts using iridium photoredox catalysis. Benzylic and aryl radical could be readily generated under mild conditions and subsequently engaged in hydrodeamination reactions and in radical couplings for the formation of C-C, C-B and C-P bonds. This work illustrates that readily available and stable ammonium salts could be used as convenient radical precursors via C-N bond cleavage and constitute an attractive alternative to more classical radical precursors derived from amines. Very recently, we have also turned our attention to the use of electrochemistry, as an alternative to photoredox catalysis, to promote such C-N bond activation thanks to its ability to fine-tune the potential and therefore better control reactivity.

Relevant publications:

J. Annibaletto, C. Jacob, C. Theunissen, Org. Lett. 2022, 24, 4170; C. Theunissen, Chimie Nouvelle 2022, 140, 8; C. Jacob, J. Annibaletto, C. Theunissen, Synlett 2025, 36, 1729.