Anthraquinones as Greener Photocatalysts for Cross-Dehydrogenative Coupling Processes – ACDC

Photoredox catalysis has rapidly emerged as a game-changer in aromatic C-H activation, driving innovation in late-stage functionalization across a spectrum of industries, from pharmaceuticals to advanced electronic semiconductors. Among its most effective uses is cross-dehydrogenative coupling (CDC), known for its exceptional atom economy and efficiency. However, conventional photo-driven CDC processes face significant limitations: they often rely on harsh oxidants and suffer from low quantum efficiencies due to unwanted competitive back electron transfer, restricting their utility to a narrow range of substrates.
This project represents a paradigm shift by harnessing anthraquinones (AQs) as environmentally friendly photocatalysts for CDC reactions. AQs stand out for their ability to form stable triplet radical ion pairs with aromatic compounds, enabling highly selective Car-N or Car-S bond formation under mild conditions. This novel catalytic approach opens doors to unprecedented inter or intra-molecular synthetic routes, particularly suited for complex, late-stage functionalization.
Our research will expand the scope of CDC reactions by leveraging a diverse library of AQs and integrating cutting-edge spectroscopy and computational modeling to fine-tune reaction mechanisms. Crucially, this project prioritizes sustainability by developing heterogenized AQ-based photocatalysts, enabling greener solvent use and process intensification in continuous flow systems. This approach promises to redefine the efficiency and environmental impact of photocatalytic transformations in organic synthesis.