Potassium Iodide → 6-Dimethylamino-3-methylbenzofuran

HRID 1460736Notes

Reaction equation

HRID 1460736 reaction equation
[CH3:1][N:2]([CH3:10])[C:3]1[CH:4]=[C:5]([OH:9])[CH:6]=[CH:7][CH:8]=1.C(=O)([O-])[O-].[K+].[K+].[I-].[K+].Cl[CH2:20][C:21](=O)[CH3:22]>CN(C)C=O>[CH3:1][N:2]([CH3:10])[C:3]1[CH:8]=[CH:7][C:6]2[C:21]([CH3:22])=[CH:20][O:9][C:5]=2[CH:4]=1

Participants

6

Reactant 4

HCID 4875Potassium IodideHCID 6571ChloroacetoneHCID 74213-(Dimethylamino)phenolHCID 11430Potassium Carbonate

Product 1

HCID 199824716-Dimethylamino-3-methylbenzofuranYield 20.1%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

140 g of 3-dimethylaminophenol are dissolved in 700 ml of dimethylformamide. 152 g of potassium carbonate and 28 g of potassium iodide are added. 101.8 g of chloroacetone are then added dropwise in the course of one hour; afterwards the mixture is stirred at room temperature for 20 hours. The reaction solution is filtered and the dimethylformamide and unconverted chloroacetone are distilled off (30° C., 1 mm Hg). Water is added to the residue, and the mixture is basified with concentrated sodium hydroxide solution and filtered. The crude product is taken up in 1 liter of ethanol, 115 ml of concentrate hydrochloric acid are added, and the mixture is heated to 80° C. 40 hours later the mixture is cooled down, treated with active carbon and filtered. The alcohol is removed, water is added to the residue, and the mixture is basified with concentrated sodium hydroxide solution. The crude product is filtered off and recrystallized from a mixture of hexane and diethyl ether (10:1) to give 36 g of 6-dimethylamino-3-methylbenzofurane.

Workup

  1. filtrationThe reaction solution is filtered
  2. distillationthe dimethylformamide and unconverted chloroacetone are distilled off (30° C., 1 mm Hg)
  3. additionWater is added to the residue
  4. filtrationfiltered
  5. addition115 ml of concentrate hydrochloric acid are added
  6. temperaturethe mixture is heated to 80° C
  7. temperature40 hours later the mixture is cooled down
  8. additiontreated with active carbon
  9. filtrationfiltered
  10. customThe alcohol is removed
  11. additionwater is added to the residue
  12. filtrationThe crude product is filtered off
  13. customrecrystallized from a mixture of hexane and diethyl ether (10:1)

Sources & evidence

ORD record
ord-fcb2eb3c366f48908ad51025fdfb4b8d
Source dataset
uspto-grants-1991_12
Patent number
US05071986

Reaction notes

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