Acetic Acid → HCID 22561714, compound

Participants

Reaction Steps

To the suspension of 4-(2,4-difluoro-phenyl)-1H-indole (6.42 g, 28 mmol) in t-BuOH: ethanol: acetic acid (177 mL: 105 mL: 55 mL) was added pyridinium tribromide (27 g, 84 mmol) portionwise. The mixture was stirred at room temperature for 3 hours, and then to the mixture was added with acetic acid (136 mL). Zinc dust (9.8 g, 150 mmol) was added to the reaction mixture portionwise. After stirring for one hour, any unreacted zinc was filtered off and most of the solvent was removed under reduced pressure. The residue was diluted with ethyl acetate, washed with water (5×), neutralized with 1N HCl, washed with sat. NaHCO3, brine, dried over Na2SO4, concentrated and triturated with ether to give 5.16 g (75%) of 4-(2,4-difluoro-phenyl) 1,3-dihydro-indol-2-one.

Provenance & Evidence