反应详情

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.

1. temperatureat reflux for 3 hours
2. temperaturecooled
3. temperatureThe mixture is heated on a hot plate until nearly one phase
4. filtrationfiltered hot
5. additionThe warm filtrate is immediately treated with 50 mL of 4.0N HCl
6. filtrationthe precipitated solid is filtered
7. washwashed with 25% methanol in water