Water → 4-Pyridin-3-yl-1,3-dihydroindol-2-one

HRID 988141Notes

Reaction equation

HRID 988141 reaction equation
[Br-].[Br-].[Br-].[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1.[N:22]1[CH:27]=[CH:26][CH:25]=[C:24]([C:28]2[CH:36]=[CH:35][CH:34]=[C:33]3[C:29]=2[CH:30]=[CH:31][NH:32]3)[CH:23]=1.[OH2:37]>CC(O)(C)C.C(O)C.C(O)(=O)C.[Zn]>[N:22]1[CH:27]=[CH:26][CH:25]=[C:24]([C:28]2[CH:36]=[CH:35][CH:34]=[C:33]3[C:29]=2[CH2:30][C:31](=[O:37])[NH:32]3)[CH:23]=1

Participants

8

Reactant 3

HCID 962WaterHCID 13694122HCID 13694122, compoundHCID 21124087Pyridiniumtribromide

Product 1

HCID 221354074-Pyridin-3-yl-1,3-dihydroindol-2-oneYield 100%

Reagents, catalysts & solvents 4

HCID 23994ZincCatalystHCID 176Acetic AcidSolvent2×HCID 702EthanolSolventHCID 6386tert-ButanolSolvent

Procedure

Pyridinium tribromide (90% (Aldrich), 5.5 g, 15.3 mmol) was added portion-wise over 10 minutes to a suspension of 4-pyridin-3-yl-1H-indole (1 g, 5.1 mmol) in 2-methyl-2-propanol (30 mL), ethanol (20 mL) and acetic acid (10 mL). The mixture was stirred at room temperature for 2 hours and then acetic acid (50 mL) was added. After stirring for an additional hour, water (0.5 mL) and zinc dust (3.3 g, 51 mmol) were added and stirring was continued for another hour. Residual zinc dust was filtered and washed with methanol. The filtrate was concentrated and the syrupy residue was stirred in water (100 mL) overnight. The solid which formed was filtered, washed with water to remove zinc and pyridine salts and dried under high vacuum to give 1.1 g (100%) of 4-pyridin-3-yl-1,3-dihydro-indol-2-one.

Workup

  1. stirringAfter stirring for an additional hour
  2. stirringstirring
  3. waitwas continued for another hour
  4. filtrationResidual zinc dust was filtered
  5. washwashed with methanol
  6. concentrationThe filtrate was concentrated
  7. stirringthe syrupy residue was stirred in water (100 mL) overnight
  8. customThe solid which formed
  9. filtrationwas filtered
  10. washwashed with water
  11. customto remove zinc and pyridine salts
  12. customdried under high vacuum

Sources & evidence

ORD record
ord-533b04cbf1974be68b251ce59a47bf1f
Source dataset
uspto-grants-2003_10
Patent number
US06635640B2

Reaction notes

Loading…