Ethyl 7-(2-{[di-tert-butyl(phenyl)silyl]oxy}-1-methylethoxy)-5-[4-(methylsulfonyl)phenoxy]-1H-indole-2-carboxylate → 7-(2-{[Di-tert-butyl(phenyl)silyl]oxy}-1-methylethoxy)-5-[4-(methylsulfonyl)phenoxy]-1H-indole-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Ethyl 7-(2-{[di-tert-butyl(phenyl)silyl]oxy}-1-methylethoxy)-5-[4-(methylsulfonyl)phenoxy]-1H-indole-2-carboxylate (2.4 g) was dissolved in a mixed solvent of tetrahydrofuran (10 mL)-ethanol (10 mL), 1M aqueous sodium hydroxide solution (5 mL) was added, and the mixture was stirred at 50° C. for 1 hr. 1M Aqueous sodium hydroxide solution (1 mL) was added to the reaction solution, and the mixture was stirred at 50° C. for 40 min. 1M Aqueous sodium hydroxide solution (1 mL) was added again, and the mixture was further stirred at 50° C. for 30 min. The reaction solution was allowed to cool to room temperature, and concentrated under reduced pressure. Water was added to the residue, and the mixture was neutralized with 1M hydrochloric acid, and subjected to extraction with ethyl acetate. The organic layer was washed with saturated brine, dried over magnesium sulfate, filtrated, and concentrated under reduced pressure to give the title compound (1.9 g, yield 83%) as a pale-red amorphous solid. MS 644 (MH+).

Provenance & Evidence