Reacción #85599

Ecuación de reacción

2,2,6,6-Tetramethylpiperidine

N,N′,N″,N″-pentamethyldiethylene triamine

compound 1

4-methylcatechol

n-BuLi

THF

1,1,2-trichloro-1,2,2-trifluoroethane

→

title compound

Rendimiento 73.8%

4-chloro-5-fluoro-1H-indole-3-carboxylic acid

Rendimiento 73.8%

Disolventes

Water

—

hexanes

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturawas warmed to 25° C
2. 2
   LavadoThe organic phase was washed with brine
3. 3
   Secadodried with sodium sulfate
4. 4
   Filtraciónfiltered
5. 5
   Concentraciónconcentrated in vacuo
6. 6
   OtroThe residue was purified by SiO2 column chromatography (PE)

Procedimiento

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.

Fuente