Flow Photoelectrocatalysis via Hydrogen-Atom Transfer: net-oxidative C-H to C-C bond conversion

Currently, direct C-H to C-C bond conversion achieved via photocatalyzed Hydrogen Atom Transfer is mainly limited to redox neutral transformations, where the electrons in the reagents are preserved in the product of interest.

The few non-redox neutral approaches reported are oxidative processes that require aggressive oxidants or fragile dual-catalytic systems to remove the extra electrons.HAT-TRICK combines photocatalyzed Hydrogen Atom Transfer (p-HAT), electrochemistry (e-chem) and flow chemistry (flow-chem) to deliver a game-changing and easy-to-use technology to drive these net-oxidative transformations sustainably.On one side, p-HAT will be used as the substrate activation manifold because it consists in the direct activation of a C-H bond in the substrate by the excited state of a photocatalyst to deliver an organoradical to be exploited for synthetic purposes.

This methodology shows unrivalled atom-efficiency, step-economy and sustainability and waives chemists from installing activating groups in the molecule.

On the other side, e-chem stands as a unique way to remove extra electrons from the reaction mixture, since an anode works as a recyclable, bottomless sink of electrons.

This strategy outperforms those based on chemical oxidants as it allows to have absolute control on the applied potential, which is vital in the presence of the fleeting reactive intermediates that will be generated via p-HAT.

Finally, flow-chem consistutes a godsend for this project: in a flow electrochemical cell the interelectrode distance can be reduced to micrometers, ensuring that radical intermediates are generated next to the anode to encourage the needed oxidation.

On top of that, flow-chem innate modularity enables the possibility of performing tandem reactions.Given the above, HAT-TRICK will open new avenues in organic synthesis and will allow to run cross-dehydrogenative couplings (RO1), functionalization of alkenes (RO2) and the dehydrogenation of alkanes (RO3).