Sulfuric Acid → 3-Bromo-4-chloro-5-fluoro-2-picoline

Reaktionsgleichung

[Cl:1][C:2]1[C:7]([F:8])=[CH:6][N:5]=[C:4]([CH3:9])[CH:3]=1.[Br:10]Br.S(=O)(=O)(O)O>>[Br:10][C:3]1[C:4]([CH3:9])=[N:5][CH:6]=[C:7]([F:8])[C:2]=1[Cl:1]

Komponenten

Edukt 3

HCID 1118Sulfuric Acid

HCID 24408Bromine

HCID 196914104-Chloro-5-fluoro-2-methylpyridine2×

Produkt 1

HCID 196914363-Bromo-4-chloro-5-fluoro-2-picoline

Versuchsvorschrift

4-Chloro-5-fluoro-2-picoline, the product of Example 66, is treated with bromine in fuming sulfuric acid containing 65% sulfur trioxide for 7 hours at 80° C. as described by L. van der Does and H. J. Hertog in Rec Trav Chim 81: 864 (1965) to afford the title compound.