Reaktion #49865

Reaktionsgleichung

water

sodium hydroxide

1,1-dimethylethyl 1-methyl-3(1-methylethoxy)-5-(phenylmethoxy)-1H-indole-2-carboxylate

water

→

product

Ausbeute 88.4%

1-Methyl-3-(1-methylethoxy)-5-(phenylmethoxy)-1H-indole-2-carboxylic acid

Ausbeute 88.4%

Lösungsmittel

2-methoxyethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturat reflux for 3 hours
2. 2
   Temperaturcooled
3. 3
   TemperaturThe mixture is heated on a hot plate until nearly one phase
4. 4
   Filtrationfiltered hot
5. 5
   workup.ADDITIONThe warm filtrate is immediately treated with 50 mL of 4.0N HCl
6. 6
   Filtrationthe precipitated solid is filtered
7. 7
   Waschenwashed with 25% methanol in water

Vorschrift

A suspension of 1,1-dimethylethyl 1-methyl-3(1-methylethoxy)-5-(phenylmethoxy)-1H-indole-2-carboxylate (5.6 g, 14 mmol) in 80 mL of 2-methoxyethanol is treated with a solution of 50% aqueous sodium hydroxide (5.0 g, 63 mmol) followed by the addition of 15 mL of water. The mixture is stirred at reflux for 3 hours, then cooled and added to 700 mL of water. The mixture is heated on a hot plate until nearly one phase and filtered hot. The warm filtrate is immediately treated with 50 mL of 4.0N HCl. After cooling to room temperature, followed by 1 hour in an ice bath, the precipitated solid is filtered and washed with 25% methanol in water to give 4.2 g (88%) of product suitable for further synthesis. A sample recrystallized from ethyl acetate-hexane has mp 136° C.-dec.

Quelle