Visible-light photoredox-catalyzed selective carboxylation of C(sp3)?F bonds with CO2

•Selective carboxylation of C(sp3)–F bonds with CO2•Mild visible-light photoredox catalytic systems•Broad substrate scope for various carboxylation•The dual role CO2 demonstrated by mechanistic studies and DFT calculations In the past decades, carbon dioxide (CO2) has been widely used as a C1 building block in organic synthesis because its high abundance, easy availability, renewability. Notably, reductive carboxylations electrophiles offer straightforward access to carboxylic acids step economy, preventing handling moisture-sensitive organometallic reagents. However, both C–F are inert, under transition-metal-free conditions never investigated. Herein, we report novel selective via catalysis. demonstrate that unreactive fluorinated substrates would undergo single-electron transfer reduction situ generated radical anions, which is reductive. We anticipate our findings could provide guidance general research on utilization other inert substrates, including biomass. 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