Sodium Hydroxide → HCID 66755708, compound

Participants

Reaction Steps

Methyl 1-(3,4-dichlorophenylsulfonyl)indoline-2-carboxylate (49.8 g, 128.92 mmol) was dissolved in a mixture of methanol/dioxane/4 M NaOH (15/4/1, 960 ml, 193.38 mmol NaOH, 1.5 eq.), and further 4 M NaOH (145 ml, 580.14 mmol, 4.5 eq.) was added thereto. The solution was stirred overnight at room temperature and then concentrated using a rotary evaporator. Ethyl acetate was added to the residue, and the mixture was washed with 0.5 M KHSO4. The aqueous phase was then extracted three times with ethyl acetate, and the combined organic phases were washed with saturated NaCl solution (500 ml), dried (sodium sulfate) and concentrated in vacuo. The residue was washed with diethyl ether, filtered and dried.

Provenance & Evidence