Potassium Carbonate → methyl 5-bromobenzofuran-2-carboxylate

HRID 252849Notes

Reaction equation

HRID 252849 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([OH:10])=[C:6]([CH:9]=1)[CH:7]=O.Br[CH2:12][C:13]([O:15][CH3:16])=[O:14].C(=O)([O-])[O-].[K+].[K+]>CN(C=O)C>[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[O:10][C:12]([C:13]([O:15][CH3:16])=[O:14])=[CH:7][C:6]=2[CH:9]=1

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 60984Methyl bromoacetateHCID 728635-Bromosalicylaldehyde

Product 1

HCID 620341methyl 5-bromobenzofuran-2-carboxylateYield 35%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a stirred solution of 5-bromo-2-hydroxybenzaldehyde (14a, 1.5 g, 7.46 mmol) in DMF (20 mL), was added methyl bromoacetate (8.21 mmol, 0.78 mL) and potassium carbonate (4.12 g, 29.84 mmol). The reaction mixture was heated at 80° and stirred for 15 hours, quenched with water (100 mL) and extracted with ethyl acetate (2×50 mL). The organic phase was dried with sodium sulfate, concentrated and the residue was purified by flash chromatography on silica gel, eluent hexanes-EtOAc (9:1). This afforded 244a as a white solid (650 mg, 35% yield). 1H NMR: (DMSO) δ 8.01-8.00 (m, 1H), 7.73-7.70 (m, 2H), 7.66-7.63 (m, 1H), 3.89 (s, 3H).

Workup

  1. temperatureThe reaction mixture was heated at 80°
  2. customquenched with water (100 mL)
  3. extractionextracted with ethyl acetate (2×50 mL)
  4. dry with materialThe organic phase was dried with sodium sulfate
  5. concentrationconcentrated
  6. customthe residue was purified by flash chromatography on silica gel, eluent hexanes-EtOAc (9:1)

Sources & evidence

ORD record
ord-17626961d0f644ba96ca129ce83f8ca6
Source dataset
uspto-grants-2011_01
Patent number
US07868205B2

Reaction notes

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