Acetone → 6-Hydroxybenzofuran

HRID 869864Notes

Reaction equation

HRID 869864 reaction equation
[BH4-].[Na+].[Si]([O:10][C:11]1[CH:20]=[CH:19][C:14]2[C:15](=O)[CH2:16][O:17][C:13]=2[CH:12]=1)(C(C)(C)C)(C)C.CC(C)=O.Cl>CO.O>[O:17]1[C:13]2[CH:12]=[C:11]([OH:10])[CH:20]=[CH:19][C:14]=2[CH:15]=[CH:16]1

Participants

7

Reactant 4

HCID 180AcetoneHCID 313Hydrochloric AcidHCID 4311764Sodium borohydrideHCID 234389036-((Tert-butyldimethylsilyl)oxy)benzofuran-3(2H)-one

Product 1

HCID 1288446-HydroxybenzofuranYield 85.5%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

NaBH4 (6.0 g, 160 mmol) was added to a solution of 6-(tert-butyldimethylsilyloxy)benzofuran-3(2H)-one (40.0 g, 151 mmol) in MeOH (800 mL) at room temperature. After stirring at room temperature for 2 h, the reaction mixture was treated with acetone. Subsequently 4N HCl were added to the mixture and the stirring was continued for 3 h at room temperature. The mixture was diluted with water and extracted with ethyl acetate (3×1000 mL). The extract was washed with brine, dried, concentrated in vacuo and purified by column chromatography on silica gel (5-10% ethyl acetate in petroleum ether) to afford the pure product (17.0 g, 85.5% yield). 1H NMR (300 MHz, CDCl3) δ: 7.51 (d, J=2.1, 1H), 7.41 (d, J=8.4, 1H), 7.02 (d, J=1.8, 1H), 6.81 (dd, J=8.4, 2.1, 1H), 6.68 (dd, J=2.1, 0.9, 1H), 5.5 (br s, 1H).

Workup

  1. waitthe stirring was continued for 3 h at room temperature
  2. extractionextracted with ethyl acetate (3×1000 mL)
  3. washThe extract was washed with brine
  4. customdried
  5. concentrationconcentrated in vacuo
  6. custompurified by column chromatography on silica gel (5-10% ethyl acetate in petroleum ether)

Sources & evidence

ORD record
ord-9063c301c23546798f8a2e251a9bf4d0
Source dataset
uspto-grants-2015_03
Patent number
US08969386B2

Reaction notes

Loading…