ethyl 7-fluoro-1H-indole-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of sodium hydride (73.2% dispersion in oil; 962 mg) in dry THF (50 ml) under nitrogen at 0° was added ethyl 7-fluoro-1H-indole-2-carboxylate (5.5 g) in dry THF (50 ml), and the mixture was stirred for 1 h. Methyl iodide (2.16 ml) was added, and the mixture was stirred for 2 h, then at 50° for 3 h. The mixture was quenched with 10% aqueous THF (5 ml), diluted with ether (500 ml), washed with saturated brine solution (2×500 ml), dried and evaporated in vacuo to leave an oil. This was purified by FCC eluting with hexane:ether (20:1) to give the title compound (4.53 g) as a liquid, t.l.c. (hexane:ether, 20:1) Rf 0.37. the mixture was stirred for 2 h at 50° for 3 h The mixture was quenched with 10% aqueous THF (5 ml) diluted with ether (500 ml) washed with saturated brine solution (2×500 ml) dried evaporated in vacuo to leave an oil This was purified by FCC eluting with hexane:ether (20:1)