Ethyl bromoacetate → Ethyl 5-methyl-1-benzofuran-2-carboxylate

HRID 252804Notes

Reaction equation

HRID 252804 reaction equation
[OH:1][C:2]1[CH:9]=[CH:8][C:7]([CH3:10])=[CH:6][C:3]=1[CH:4]=O.C([O-])([O-])=O.[K+].[K+].Br[CH2:18][C:19]([O:21][CH2:22][CH3:23])=[O:20]>CN(C=O)C>[CH3:10][C:7]1[CH:8]=[CH:9][C:2]2[O:1][C:18]([C:19]([O:21][CH2:22][CH3:23])=[O:20])=[CH:4][C:3]=2[CH:6]=1

Participants

5

Reactant 3

HCID 7748Ethyl bromoacetateHCID 11430Potassium CarbonateHCID 69184Benzaldehyde, 2-hydroxy-5-methyl-

Product 1

HCID 13157013Ethyl 5-methyl-1-benzofuran-2-carboxylateYield 31%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a stirred suspension of 2-hydroxy-5-methylbenzaldehyde (5 g, 36.7 mmol) and K2CO3 (12.7 g, 91.8 mmol) in DMF (30 mL), ethyl bromoacetate (4.07 ml, 36.7 mmol) was added drop-wise. This mixture was allowed to stir for two hours under nitrogen at room temperature, and was then heated to 80° C. and stirred overnight. The reaction was quenched with H2O to form a precipitate which was collected by filtration and purified by flash chromatography (eluent 5% EtOAc in hexane) to give the title compound 25 (2.30 g, 31%). 1H-NMR (CDCl3) δ: 1.45 (t, J=7.0 Hz, 3H); 2.47 (s, 3H); 4.45 (q, J=7.0 Hz, 2H); 7.26 (m, 1H); 7.46 (m, 3H).

Workup

  1. additionwas added drop-wise
  2. temperaturewas then heated to 80° C.
  3. stirringstirred overnight
  4. customThe reaction was quenched with H2O
  5. customto form a precipitate which
  6. filtrationwas collected by filtration
  7. custompurified by flash chromatography (eluent 5% EtOAc in hexane)

Sources & evidence

ORD record
ord-b930c7e699374458a498e877b4abae1a
Source dataset
uspto-grants-2011_01
Patent number
US07868205B2

Reaction notes

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