Boron trifluoride → 6-Methoxy-1-benzothiophene

HRID 454799Notes

Reaction equation

HRID 454799 reaction equation
C(O[CH:4](OCC)[CH2:5][S:6][C:7]1[CH:12]=[CH:11][CH:10]=[C:9]([O:13][CH3:14])[CH:8]=1)C.FB(F)F.C(=O)(O)[O-].[Na+]>ClCCl>[CH3:14][O:13][C:9]1[C:8]2[CH:4]=[CH:5][S:6][C:7]=2[CH:12]=[CH:11][CH:10]=1.[CH3:14][O:13][C:9]1[CH:10]=[CH:11][C:12]2[CH:4]=[CH:5][S:6][C:7]=2[CH:8]=1

Participants

6

Reactant 3

HCID 6356Boron trifluorideHCID 516892Sodium BicarbonateHCID 13642516(2,2-Diethoxyethyl)(3-methoxyphenyl)sulfane

Product 2

HCID 126238694-Methoxy-benzo(b)thiopheneYield 16%HCID 136342376-Methoxy-1-benzothiopheneYield 60%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To the obtained (2,2-diethoxyethyl)(3-methoxyphenyl)sulfane (91, 3.6 g, 14.0 mmol) dissolved in a dichloromethane solution (70 mL) was slowly added trifluoroborane etherate (BF3-Et2O; 1.75 mL, 13.72 mmol) at room temperature under nitrogen, and the reaction mixture was stirred for one hour and neutralized with a sodium bicarbonate solution at room temperature. Organic layer was isolated, organic compounds in water were extracted with dichloromethane, the recovered organic solution was evaporated after a treatment with sodium sulfate, and concentrated under reduced pressure. After concentration, residues were purified by column chromatography to give the target compounds 4-methoxybenzothiophene (92a, 368 mg, 16%) and 6-methoxybenzothiophene compounds (92b, 1.38 g, 60%) as transparent liquids.

Workup

  1. customat room temperature
  2. customOrganic layer was isolated
  3. extractionorganic compounds in water were extracted with dichloromethane
  4. customthe recovered organic solution was evaporated after a treatment with sodium sulfate
  5. concentrationconcentrated under reduced pressure
  6. concentrationAfter concentration, residues
  7. customwere purified by column chromatography

Sources & evidence

ORD record
ord-f26fd57827504cbeb4ca9ccc8af1b3af
Source dataset
uspto-grants-2013_07
Patent number
US08497260B2

Reaction notes

Loading…