Potassium Carbonate → Ethyl 5-methyl-1-benzofuran-2-carboxylate

HRID 1773225Notes

Reaction equation

HRID 1773225 reaction equation
[CH:1]([C:3]1[CH:15]=[C:14]([CH3:16])[CH:13]=[CH:12][C:4]=1[O:5][CH2:6][C:7]([O:9][CH2:10][CH3:11])=[O:8])=O.C([O-])([O-])=O.[K+].[K+]>CN(C=O)C>[CH3:16][C:14]1[CH:13]=[CH:12][C:4]2[O:5][C:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])=[CH:1][C:3]=2[CH:15]=1

Participants

4

Reactant 2

HCID 11430Potassium CarbonateHCID 13157005Ethyl (2-formyl-4-methylphenoxy)acetate

Product 1

HCID 13157013Ethyl 5-methyl-1-benzofuran-2-carboxylateYield 58.3%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
90 °C

Procedure

To a solution of ethyl 2-(2-formyl-4-methylphenoxy)acetate (2.24 g, 10.08 mmol) in 15 mL of DMF was added K2CO3 (2.79 g, 20.16 mmol), the mixture was stirred under nitrogen at 90° C. for 3 hr. After cooling to room temperature, the mixture was filtered through Celite, and washed with DCM. The combined filtrate was concentrated, and the resulting residue was purified by silica gel flash chromatography, 100% Heptane-20% Ethyl Acetate/80% Heptane, to give a white solid, ethyl 5-methylbenzofuran-2-carboxylate (1.2 g). LCMS retention time=1.54 minutes (LC method 3); MS (m+1)=204.8. 1H NMR (400 MHz, DMSO-d6) δ 1.33 (t, J=7.1 Hz, 3H), 2.41 (s, 3H), 4.35 (q, J=7.1 Hz, 2H), 7.34 (dd, J=8.5, 1.4 Hz, 1H), 7.55-7.63 (m, 2H), 7.68 (d, J=0.9 Hz, 1H).

Workup

  1. temperatureAfter cooling to room temperature
  2. filtrationthe mixture was filtered through Celite
  3. washwashed with DCM
  4. concentrationThe combined filtrate was concentrated
  5. customthe resulting residue was purified by silica gel flash chromatography, 100% Heptane-20% Ethyl Acetate/80% Heptane

Sources & evidence

ORD record
ord-dcb5d7eb4ac9455d94d36ce52a92f51a
Source dataset
uspto-grants-2016_02
Patent number
US09255093B2

Reaction notes

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