Reacción #5463

Ecuación de reacción

sodium hydride

indole-3-carboxylic acid

sodium hydroxide

Dimethylsulfate

→

colorless crystals

Rendimiento 75.3%

1-Methyl-1H-indole-3-carboxylic acid

Rendimiento 75.3%

Disolventes

N,N-dimethylformamide

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaA cooled
2. 2
   Temperaturacooled
3. 3
   FiltraciónThe suspension was filtered
4. 4
   Lavadothe wet solid was washed with water
5. 5
   Temperaturarefluxed for 30 minutes
6. 6
   Otrothe methanol was removed in vacuo
7. 7
   ExtracciónThe aqueous solution was extracted with ether (50 mL)
8. 8
   FiltraciónThe suspension was filtered
9. 9
   Lavadothe solid was washed with water
10. 10
    Secadodried exhaustively m vacuo in the presence of Drierite
11. 11
    OtroRecrystallization from acetonitrile

Procedimiento

A cooled (0° C.) suspension of 60% sodium hydride-oil dispersion (0.96 g, 24 mmol) in anhydrous N,N-dimethylformamide (15 mL) under nitrogen was treated in portions with indole-3-carboxylic acid (1.62 g, 10 mmol), and the mixture was stirred at 45°±5° C. for 30 minutes. Dimethylsulfate (3.03 g, 24 mmol) was added, and the mixture was heated to 100° C. for 30 minutes, cooled, and added to ice water (100 mL). The suspension was filtered and the wet solid was washed with water and taken up in 50% aqueous methanol (40 mL). The mixture was treated with 50% aqueous sodium hydroxide (3.0 g, 37.5 mmol) and refluxed for 30 minutes, then the methanol was removed in vacuo and replaced with water. The aqueous solution was extracted with ether (50 mL), then acidified with 3N HCl to pH 3 (15 mL). The suspension was filtered and the solid was washed with water and dried exhaustively m vacuo in the presence of Drierite. Recrystallization from acetonitrile afforded 1.32 g (75%) of colorless crystals; mp 201°-202° C. (dec).

Fuente