Université de Strasbourg

Dual catalysis

Dual catalysis merging visible-light photocatalysis and C-H activation: new strategy towards all-carbon quaternary stereogenic centres

USIAS Fellow : Joanna Wencel-Delord

Developing conceptually novel, more eco-reliable transformations, building up molecular scaffolds inaccessible via standard methodologies and designing unprecedented catalytic systems are urgent challenges of the fundamental research in organic chemistry. In particular, alkylation reactions involving sterically hindered coupling partners, with, ideally, concomitant formation of stereogenic centers, remain particularly demanding. The objective of “Dual catalysis merging visible-light photocatalysis and C-H activation: new strategy towards all-carbon quaternary stereogenic centres” project is to respond to this important issue by devising an original dual catalysis benefiting from two expanding fields of organic chemistry: C-H activation and photoactivation.

The direct functionalization establishes itself as sustainable strategy to convert latent C-H bonds into desired C-C and C-X bonds. However, such transition metal-catalysis is less suited for the activation of aliphatic substrates, in particular if hindered C(sp3)-H bonds are considered. In contrast, visible light photoredox activation has recently emerged as an appealing strategy to access sterically congested, highly active aliphatic species. The ambition of our project is to merge such two complementary activation modes in a synergistic catalysis to reach challenging sp2-sp3 and sp3-sp3 couplings. In such transformations, one aromatic or aliphatic non-prefunctionalized substrate will be activated via direct insertion of the metal into a C-H bond, whereas a sterically congested aliphatic active moiety will be generated via single electron transfer (SET). After some initial efforts concerning proof-of-concept work, our efforts will rapidly focus on asymmetric transformations. Our supreme goal is to apply this approach to build-up difficult to access all-carbon quaternary stereogenic centers.

Investissements d'Avenir