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Speciation-Controlled C-F Bond Functionalization Enabled by Zwitterionic Pnictinidenes
Irene Sánchez-Sordo1, Sergio Fernandez1, Selwin Fernando1,2
1Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, London, UK.
Angewandte Chemie (International Ed. in English)
|July 21, 2026
Summary
Zwitterionic pnictinidenes enable diverse C-F bond functionalization via a novel redox-neutral pathway. This platform expands catalytic defluorination beyond traditional hydrodefluorination, offering new avenues for C-X bond formation.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Fluorine Chemistry
Background:
- Low-valent pnictogen compounds are emerging as redox catalysts for C-F bond activation.
- Current catalytic methods are often limited to hydrodefluorination pathways, relying on metallomimetic reductive elimination.
Purpose of the Study:
- To develop a novel defluorinative functionalization platform using zwitterionic pnictinidenes.
- To enable the formation of diverse C-X bonds (X = C, O, S, N, P, Se) from polyfluoro(hetero)arenes under mild conditions.
Main Methods:
- Utilized zwitterionic pnictinidenes as catalysts for C-F bond functionalization.
- Employed experimental studies and Density Functional Theory (DFT) calculations to elucidate the reaction mechanism.
- Investigated the formation of various C-X bonds from polyfluoro(hetero)arenes.
Main Results:
- Developed a platform for defluorinative functionalization mediated by zwitterionic pnictinidenes.
- Achieved the formation of diverse C-X bonds under mild reaction conditions.
- DFT studies revealed that catalysis proceeds through Sb(III)-F species via a redox-neutral manifold, distinct from a potential Sb(I)/Sb(III) redox cycle.
Conclusions:
- Catalyst speciation is a critical factor determining the mechanistic pathway (redox vs. redox-neutral) in pnictogen-mediated C-F activation.
- Strategies to control ligand scrambling can unlock alternative catalytic manifolds.
- This work expands the scope of C-F bond functionalization and provides insights into pnictogen-based catalysis.
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