Hydrochloric Acid → 3-Methyl-4-allyloxy-7-(2-thienoyl)benzofuran

HRID 1084858Notes

Reaction equation

HRID 1084858 reaction equation
[CH3:1][C:2]1[C:6]2[C:7]([OH:18])=[CH:8][CH:9]=[C:10]([C:11]([C:13]3[S:14][CH:15]=[CH:16][CH:17]=3)=[O:12])[C:5]=2[O:4][CH:3]=1.C(=O)([O-])[O-].[K+].[K+].[CH2:25](Br)[CH:26]=[CH2:27].Cl>CC(C)=O.O>[CH3:1][C:2]1[C:6]2[C:7]([O:18][CH2:27][CH:26]=[CH2:25])=[CH:8][CH:9]=[C:10]([C:11]([C:13]3[S:14][CH:15]=[CH:16][CH:17]=3)=[O:12])[C:5]=2[O:4][CH:3]=1

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 7841Allyl bromideHCID 11430Potassium CarbonateHCID 151240033-Methyl-4-hydroxy-7-(2-thienoyl)benzofuran

Product 1

HCID 151240043-Methyl-4-allyloxy-7-(2-thienoyl)benzofuran

Reagents, catalysts & solvents 2

HCID 180AcetoneSolventHCID 962WaterSolvent

Procedure

To a solution of compound 3 (0.50 g, 1.92 mmol) in acetone (10 mL) was added sequentially potassium carbonate (0.53 g, 3.84 mmol) and allyl bromide (0.47 g, 3.84 mmol). The mixture was heated to reflux for two hours, cooled, diluted with water (50 mL), and acidified with 2N HCl. The aqueous mixture was extracted with methylene chloride (3×25 mL) and the combined extracts dried (Na2SO4) and concentrated to an oil. The crude 3-methyl-4-allyloxy-7-(2-thienoyl)benzofuran thus obtained was sufficiently pure for further synthesis. 1H NMR d 2.44 (3H, d, J=2 Hz), 4.74 (2H, d, J=4 Hz), 5.44 (2H, m), 6.12 (1H, m), 6.71 (1H, d, J=8 Hz), 7.15 (1H, m), 7.36 (1H, d, J=2 Hz), 7.68 (3H, m).

Workup

  1. temperatureThe mixture was heated
  2. temperatureto reflux for two hours
  3. temperaturecooled
  4. extractionThe aqueous mixture was extracted with methylene chloride (3×25 mL)
  5. dry with materialthe combined extracts dried (Na2SO4)
  6. concentrationconcentrated to an oil

Sources & evidence

ORD record
ord-0ff69d11948c43f8819b1eccf179da86
Source dataset
uspto-grants-1991_04
Patent number
US05006549

Reaction notes

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