Titre: ‘‘ Electron Catalysis’’

Endroit : Pavillon Roger-Gaudry, salle S-142 

Heure : 11:00 AM

Hôte : Professeur André Charette

Résumé : 

In the lecture the concept of using the electron as a catalyst will be discussed.[1,2] It will be shown that the electron is an efficient catalyst for conducting various types of radical cascade reactions that proceed via radical and radical ion intermediates.[3] It will be emphasized how a negative charge can significantly weaken the neighbouring C-H bond and activate this bond towards H-atom transfer.[3e,j] Moreover, the activation of a C-H bond next to a C-radical towards deprotonation is a key point in the field of electron-catalysis. Extending that concept, the use of a negative charge to activate a C-C sigma-bond towards homolysis is also discussed.[3i,k] For example, electron catalyzed transition metal-free b-alkenylation-a-perfluoroalkylation of unactivated alkenes via radical 1,4 or 1,5-alkenyl migration will be presented.

It will be further shown, that readily generated vinyl boron ate complexes, generally used as substrates in the Suzuki-Miyaura coupling, are efficient radical acceptors to conduct electron-catalyzed modular synthesis comprising a radical polar cross over step.[3h] This approach has recently been successfully applied to the development of a novel method for the preparation of highly enantioenriched a-chiral ketones[3l] and a new method for radical borylation is introduced.[3n]

Informations supplémentaires

Annonce PDF de la conférence