反应详情

Intermediate (1b), 2-[5-methoxycarbonyl-2-oxo-1-(2-trimethylsilanyl-ethoxymethyl)-1,2-dihydro-pyridin-3-yl]-indole-1-carboxylic acid tert-butyl ester (2.88 g, 5.78 mmol) was stirred in a mixture of tetrahydrofuran (40 mL) and water (20 mL). Lithium hydroxide (0.469 g, 11.2 mmol) was added and the reaction stirred at reflux for 2 hours. After cooling the reaction mixture was concentrated in vacuo, and the residue was taken up in water and the pH adjusted to 5 with the careful addition of an aqueous 2M hydrochloric acid solution. This aqueous solution was extracted with dichloromethane (×3), and the combined extracts were washed with brine, dried (Na2SO4) and concentrated in vacuo to afford the desired title compound as a yellow solid 2.30 g, 85%.

1. temperatureat reflux for 2 hours
2. temperatureAfter cooling the reaction mixture
3. concentrationwas concentrated in vacuo
4. additionthe pH adjusted to 5 with the careful addition of an aqueous 2M hydrochloric acid solution
5. extractionThis aqueous solution was extracted with dichloromethane (×3)
6. washthe combined extracts were washed with brine
7. dry with materialdried (Na2SO4)
8. concentrationconcentrated in vacuo