Hydrochloric Acid → 2-Ethyl-3-acetyl-benzo[b]thiophene

HRID 436005

Reaction equation

HRID 436005 reaction equation
[CH2:1]([C:3]1[S:7][C:6]2[CH:8]=[CH:9][CH:10]=[CH:11][C:5]=2[CH:4]=1)[CH3:2].[C:12](Cl)(=[O:14])[CH3:13].Cl>ClC(Cl)C>[CH2:1]([C:3]1[S:7][C:6]2[CH:8]=[CH:9][CH:10]=[CH:11][C:5]=2[C:4]=1[C:12](=[O:14])[CH3:13])[CH3:2]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 6367Acetyl chlorideHCID 5956642-Ethylbenzo[b]thiophene

Product 1

HCID 214550882-Ethyl-3-acetyl-benzo[b]thiopheneYield 765%

Reagents, catalysts & solvents 1

HCID 63651,1-DichloroethaneSolvent

Procedure

Into a one-litre flask fitted with a mechanical stirrer and a dropping-funnel, 32.45 g (0.2 mol) of 2-ethyl-benzo[b]thiophene and 14.3 ml of acetyl chloride were introduced with 400 ml of dichloroethane. After the solution was cooled to between 5 and 10° C by means of an ice-bath, 23.2 ml (0.2 mol) of stannic chloride were introduced through the dropping-funnel. The mixture was then allowed to return to room temperature and was stirred for about 14 hours. The complex so formed was then hydrolysed with diluted hydrochloric acid. The organic and aqueous phases were separated by decantation and the aqueous phase was extracted with ether. The ethereal fraction was then added to the organic phase and the mixture was washed with water and evaporated to dryness to give, after distillation between 124°-134° C (0.01 mm/Hg), 31.3 g of 2-ethyl-3-acetyl-benzo[b]thiophene. Yield 765%.

Workup

  1. customInto a one-litre flask fitted with a mechanical stirrer and a dropping-funnel
  2. temperatureAfter the solution was cooled to between 5 and 10° C by means of an ice-bath
  3. customto return to room temperature
  4. customThe complex so formed
  5. customThe organic and aqueous phases were separated by decantation
  6. extractionthe aqueous phase was extracted with ether
  7. additionThe ethereal fraction was then added to the organic phase
  8. washthe mixture was washed with water
  9. customevaporated to dryness
  10. customto give
  11. distillationafter distillation between 124°-134° C (0.01 mm/Hg), 31.3 g of 2-ethyl-3-acetyl-benzo[b]thiophene

Sources & evidence

ORD record
ord-5cae08587a4f456aa6d3280aeaaa1394
Source dataset
uspto-grants-1977_02
Patent number
US04007204

Linked notes

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