Swarts reaction
Alkyl fluorides are made by heating an alkyl chloride or bromide with a metallic fluoride such as AgF, Hg2F2, CoF2 or SbF3.
BromoethaneCH₃CH₂BrHaloalkane - Step 1
AgF (or Hg₂F₂, CoF₂, SbF₃)
FluoroethaneCH₃CH₂FHaloalkane
How it works
- The metallic fluoride supplies fluoride ions.
- Fluoride replaces the halogen by nucleophilic substitution.
- The insoluble silver or mercury halide is left behind.
What it makes
Alkyl fluorides.
Where it fails
Direct fluorination or HF addition is not used because fluorine is too reactive.
Class 12, Chapter 6 Haloalkanes and Haloarenes
Swarts reaction: quick answers
Which reagent is used in the Swarts reaction?
AgF, Hg2F2, CoF2 or SbF3.
Why is direct fluorination not used?
Fluorine is too reactive to control, so a metallic fluoride supplies the fluoride ion instead.
Is the Swarts reaction the same as Finkelstein?
No. Finkelstein gives iodides with NaI; Swarts gives fluorides with metallic fluorides.