反应详情

To a solution of (3-carbamoyl-5-chloro-indol-1-yl)-acetic acid tert-butyl ester (455 mg, 0.973 mmol) in CH2Cl2 (6.0 mL) was added TFA (3.0 mL) at RT and stirring was continued for 2 h. Methanol was then added to the reaction mixture and volatiles were removed in vacuo. The residue was taken up in methanol and concentrated again under reduced pressure. The residue was dissolved in 1N aqueous NaOH and washed with CH2Cl2 (3×). The water phase was acidified to pH 2 by adding 6N aqueous HCl to form a white suspension. The precipitate was filtered off, washed with water and dried in vacuo to afford the crude title compound as a white solid. MS (LC/MS): 253 [M+H]+, 505 [2M+H]+; tR (HPLC conditions b): 3.99 min. The product was used in the next reaction step without further purification.

1. customwere removed in vacuo
2. concentrationconcentrated again under reduced pressure
3. dissolutionThe residue was dissolved in 1N aqueous NaOH
4. washwashed with CH2Cl2 (3×)
5. additionby adding 6N aqueous HCl
6. customto form a white suspension
7. filtrationThe precipitate was filtered off
8. washwashed with water
9. customdried in vacuo