Methyl iodide → 5-fluoro-1-methyl-1H-indole-3-carbaldehyde

Temperature

0 °C

In DMF (60 ml) was dissolved 5-fluoroindole-3-carbaldehyde (5.00 g, 30.6 mmol). Under stirring at 0° C., sodium hydride (60% in oil, 1.35 g, 33.7 mmol) was added in portions. After the reaction mixture was stirred at the same temperature for 1 hour, methyl iodide (5.72 ml, 91.9 mmol) was added thereto. The resulting mixture was stirred further at 0° C. for 2 hours. A saturated aqueous solution of ammonium chloride was added to the reaction mixture to neutralize the same, followed by extraction with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to remove the solvent. The residue was purified by chromatography on a silica gel column, whereby from ethyl acetate eluate fractions, 5-fluoro-1-methylindole-3-carbaldehyde (5.42 g, 100%) was obtained as a colorless solid.

1. stirringAfter the reaction mixture was stirred at the same temperature for 1 hour
2. stirringThe resulting mixture was stirred further at 0° C. for 2 hours
3. extractionfollowed by extraction with ethyl acetate
4. washThe extract was washed with saturated brine
5. dry with materialdried over anhydrous magnesium sulfate
6. distillationdistilled under reduced pressure
7. customto remove the solvent
8. customThe residue was purified by chromatography on a silica gel column, whereby from ethyl acetate eluate fractions

ORD record

ord-a54f4f7360934074a8763051d73eeb87

Source dataset

uspto-grants-2007_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07157487B2