Dimethylformamide → 1-Ethyl-1H-indole-3-carbaldehyde

HRID 615957Notes

Reaction equation

HRID 615957 reaction equation
CN(C)C=O.[NH:6]1[C:14]2[C:9](=[CH:10][CH:11]=[CH:12][CH:13]=2)[C:8]([CH:15]=[O:16])=[CH:7]1.[O-][CH2:18][CH3:19].C(I)C>C(OCC)C>[CH2:18]([N:6]1[C:14]2[C:9](=[CH:10][CH:11]=[CH:12][CH:13]=2)[C:8]([CH:15]=[O:16])=[CH:7]1)[CH3:19]

Participants

6

Reactant 4

HCID 6228DimethylformamideHCID 6340IodoethaneHCID 10256Indole-3-CarboxaldehydeHCID 1194401-Hydroxyethyl radical

Product 1

HCID 5990901-Ethyl-1H-indole-3-carbaldehydeYield 50%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Conditions

Temperature
55 °C

Procedure

To a 500 milliliter reaction vessel equipped with a magnetic stirrer is added 100 milliliters anhydrous dimethylformamide and 80 milliliters anhydrous ethylether. The reaction vessel is now partially immersed in an oil bath and 14.2 grams (0.098 moles) indole-3-carboxaldehyde (purified) introduced into the reaction vessel followed by the addition of 24.9 grams (0.1 moles) thallous ethoxide. The reaction mixture is then heated to a temperature in the range of about 35° - 40° C with constant stirring for a period of about 20 minutes. At the end of this period, about 15.6 grams (0.1 moles) ethyliodide is introduced into the reaction vessel and the oil bath temperature raised to about 55° C. Subsequent to the addition of the above material and prior to increase in the temperature, the reaction vessel is equipped with a reflux condenser. Heating at the above temperature is allowed to proceed for about 60 minutes. A large amount of orange/yellow precipitate is formed during this period. The reaction mixture is allowed to cool to room temperature, filtered and the filtrate poured into one liter of water. The ether layer is saved and the water layer extracted with chloroform. The chloroform extracts are combined with the ether portion and the combined solution reextracted several times with water to remove residual traces of dimethylformamide. The chloroform layer is then dried over anhydrous magnesium sulfate, filtered and flash evaporated. An oily residue which remains is crystallized from cyclohexanone. Yield: 50 - 60 percent of white platelett crystals, m. p. 103° C.

Workup

  1. customTo a 500 milliliter reaction vessel
  2. customequipped with a magnetic stirrer
  3. customThe reaction vessel is now partially immersed in an oil bath
  4. temperatureThe reaction mixture is then heated to a temperature in the range of about 35° - 40° C
  5. additionSubsequent to the addition of the above material
  6. temperatureto increase in the temperature
  7. customthe reaction vessel is equipped with a reflux condenser
  8. temperatureHeating at the above temperature
  9. waitto proceed for about 60 minutes
  10. customA large amount of orange/yellow precipitate is formed during this period
  11. temperatureto cool to room temperature
  12. filtrationfiltered
  13. additionthe filtrate poured into one liter of water
  14. extractionthe water layer extracted with chloroform
  15. customto remove residual traces of dimethylformamide
  16. dry with materialThe chloroform layer is then dried over anhydrous magnesium sulfate
  17. filtrationfiltered
  18. customflash evaporated
  19. customAn oily residue which remains is crystallized from cyclohexanone

Sources & evidence

ORD record
ord-f95e07fa8bf94a4087350923bd8c494e
Source dataset
uspto-grants-1978_02
Patent number
US04072519

Reaction notes

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