Cfc 113 → 4-chloro-5-fluoro-1H-indole-3-carboxylic acid

Temperature

-78 °C

2,2,6,6-Tetramethylpiperidine (1.06 g, 7.5 mmol), N,N′,N″,N″-pentamethyldiethylene triamine (3.46 g, 20 mmol) and compound 1 (1.45 g, 5.0 mmol) were added consecutively to a solution of n-BuLi (2.5 M in hexanes, 8 mL, 20 mmol) in THF (20 mL) and hexanes (6 mL) at −78° C. After stirring for 4 h at −78° C., the mixture was treated with 1,1,2-trichloro-1,2,2-trifluoroethane (1.18 g, 6.0 mmol) before it was warmed to 25° C. Water was added to the mixture. The organic phase was washed with brine, dried with sodium sulfate, filtered, and concentrated in vacuo. The residue was purified by SiO2 column chromatography (PE) to provide title compound (1.2 g, 73.8%) as a colorless liquid.

1. temperaturewas warmed to 25° C
2. washThe organic phase was washed with brine
3. dry with materialdried with sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was purified by SiO2 column chromatography (PE)

ORD record

ord-62f0612a44624501baa69ff92d0919ac

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09434724B2