Potassium Carbonate → Ethyl 4-hydroxy-2-methylbenzofuran-6-carboxylate

HRID 1177254Notes

Reaction equation

HRID 1177254 reaction equation
C([O:4][C:5]1[C:10]2[CH:11]=[C:12]([CH3:14])[O:13][C:9]=2[CH:8]=[C:7]([C:15]([O:17][CH2:18][CH3:19])=[O:16])[CH:6]=1)(=O)C.C(=O)([O-])[O-].[K+].[K+]>C(O)C.ClCCl>[OH:4][C:5]1[C:10]2[CH:11]=[C:12]([CH3:14])[O:13][C:9]=2[CH:8]=[C:7]([C:15]([O:17][CH2:18][CH3:19])=[O:16])[CH:6]=1

Participants

5

Reactant 2

HCID 11430Potassium CarbonateHCID 595600946-Benzofurancarboxylic acid, 4-(acetyloxy)-2-methyl-, ethyl ester

Product 1

HCID 11514065Ethyl 4-hydroxy-2-methylbenzofuran-6-carboxylateYield 95%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
60 °C

Procedure

A mixture of ethyl 4-(acetyloxy)-2-methyl-1-benzofuran-6-carboxylate in absolute ethanol (500 mL) and potassium carbonate (18 g, 0.13 mol) was stirred for 3 h at 60° C. The mixture was diluted with 500 mL of dichloromethane and the suspension was filtered. The precipitate was washed with 200 mL of dichloromethane. The combined solutions was washed with 200 mL of a 10% aqueous solution of citric acid and evaporated in vacuum to dryness. The crude product introduced into a silica gel column and eluted with hexane/ethyl acetate mixture (2:1) to give 20 g (91 mmol, 95%) of desired compound as a yellow solid. 1HNMR (DMSO d-6): 1.30 (t, H), 2.45 (s, 3H), 4.30 (qt, 2H), 6.65 (s, 1H), 7.28 (2, 1H), 7.53 (s, 1H), 10.25 (s, 1H).

Workup

  1. filtrationthe suspension was filtered
  2. washThe precipitate was washed with 200 mL of dichloromethane
  3. washThe combined solutions was washed with 200 mL of a 10% aqueous solution of citric acid
  4. customevaporated in vacuum to dryness
  5. additionThe crude product introduced into a silica gel column
  6. washeluted with hexane/ethyl acetate mixture (2:1)

Sources & evidence

ORD record
ord-34bdaca5a55c4d549bcc071f5300e895
Source dataset
uspto-grants-2010_11
Patent number
US07842713B2

Reaction notes

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