Hydrochloric Acid → HCID 86739959, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 6.4 g (20.0 mmol) of 5-chloro-7-(4-methylthiobenzoyl)indolin-2-one in 110 ml of 3N sodium hydroxide was heated at 100° C. in an oil bath and stirred under a nitrogen atmosphere for 22 hrs. The reaction mixture was diluted to 600 ml with water and then titrated to a pH of 7.5 with concentrated hydrochloric acid. The mixture was then filtered and the filter cake was extracted with 1.5 liter of hot water. The filtrate obtained was concentrated to a solid residue. This residue was dissolved in hot absolute ethyl alcohol and filtered. The filtrate obtained was concentrated to a solid which was dissolved in 300 ml of 2-propanol and filtered. The filtrate obtained was concentrated to 200 ml and cooled to 0° C., whereby a gel was obtained. This gel was left at room temperature and a crystalline solid was collected therefrom by filtration and dried to give 2.9 g (39%) of the titled compound as a yellow solid, m.p. 259°-260° C.

Provenance & Evidence