Methyl iodide → 4-Bromo-1-methyl-1H-indole-2,3-dione

HRID 1407498Notes

Reaction equation

HRID 1407498 reaction equation
[Br:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]2[C:3]=1[C:4](=[O:12])[C:5](=[O:11])[NH:6]2.[C:13](=O)([O-])[O-].[Cs+].[Cs+].IC>CN(C)C=O>[Br:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]2[C:3]=1[C:4](=[O:12])[C:5](=[O:11])[N:6]2[CH3:13]

Participants

5

Reactant 3

HCID 6328Methyl iodideHCID 10796Cesium carbonateHCID 45000124-Bromoisatin

Product 1

HCID 284924654-Bromo-1-methyl-1H-indole-2,3-dioneYield 85.4%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a stirred solution of 4-bromoisatin (90.4 g, 400 mmol) in N,N-dimethylformamide (400 mL) was added cesium carbonate (196.0 g, 600 mol) at ambient temperature. The reaction mixture was stirred for 30 min, iodomethane (37.4 mL, 600 mmol) was added and the mixture was stirred at ambient temperature for 18 h. The solid was removed by filtration, the filtrate was concentrated in vacuo, and the residue was triturated in water and washed with diethyl ether to afford 4-bromo-1-methyl-1H-indole-2,3-dione (82.0 g, 85%): 1H NMR (300 MHz, DMSO-d6) δ 7.95-7.89 (m, 1H), 7.68-7.64 (m, 1H), 7.53-7.49 (m, 1H), 3.50 (s, 3H).

Workup

  1. stirringthe mixture was stirred at ambient temperature for 18 h
  2. customThe solid was removed by filtration
  3. concentrationthe filtrate was concentrated in vacuo
  4. customthe residue was triturated in water
  5. washwashed with diethyl ether

Sources & evidence

ORD record
ord-202738ef4a534b448f6eb5ba2aafd6b5
Source dataset
uspto-grants-2014_12
Patent number
US08916580B2

Reaction notes

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