Sulfuric Acid → HCID 67153982, compound

Participants

Reaction Conditions

Reaction Steps

3.0 g of ethyl 2-(3,3-difluoropropyl)-5,5-difluoro-2-[4-[[(2E)-2-hydroxyiminoacetyl]amino]phenyl]pentanoate are added in portions to 20 ml of sulfuric acid (98%) at 50° C., during which the temperature rises to 60° C. When the addition is complete, the mixture is stirred at 50° C. for a further 120 min and subsequently poured into 400 ml of ice-water. The mixture is washed three times with 200 ml of dichloromethane/ethanol (9:1) each time, the combined organic phases are dried over sodium sulfate, filtered off and evaporated to dryness in vacuo. The crude product obtained is employed in the next reaction without further purification. Yield: 1.9 g (66%) of ethyl 2-(3,3-difluoropropyl)-2-(2,3-dioxoindolin-5-yl)-5,5-difluoropentanoate obtained; LC-MS retention time: 2.17 min.

Provenance & Evidence