Bromine → 1-(5-bromo-2,3-dihydro-1H-indol-1-yl)ethan-1-one

Participants

Reaction Steps

To N-acetylindoline, 116.6 g (0.724 mol) in a 1000 ml 3 neck flash fitted with overhead stirrer, thermometer and gas inlet (to a sodium hydroxide trap) in 150 ml acetic acid was added bromine, 32.25 ml (0.68 mol) over a period of 30 minutes. The mixture was kept at 30° C. with ice bath cooling. When addition was complete, the yellow suspension was slowly poured into one liter of ice water and solid sodium bisulfite was added to destroy any residual bromine. The resulting slightly off white solid was filtered and washed several times with water and allowed to dry overnight. The resulting solid was recrystallized from 800 ml of methanol to give 122.86 g (70.7% by weight yield) of 5-bromo-N-acetylindoline.

Provenance & Evidence