Carbon Dioxide → 7-Fluoro-1H-indole-5-carboxylic acid

Participants

Reaction Steps

To a solution of 5-bromo-7-fluoroindole 21a (1.71 mmol, 365 mg) in THF at −60° C. was added n-BuLi (1.6 M solution in hexanes, 5.2 mmol, 3.2 mL). The solution was kept at −60° C. for 4 h and was then poured onto an excess of freshly crushed dry ice. Water was added and the mixture was acidified to pH 4. The organic phase was concentrated and the residue was purified by flash column chromatography (silica gel, 35% EtOAc/hexanes) to give compound 21b.

Provenance & Evidence