Hydrochloric Acid → 2-Benzofurancarboxaldehyde, 3-methyl-

HRID 2090994Notes

Reaction equation

HRID 2090994 reaction equation
[CH3:1][C:2]1[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[O:4][C:3]=1[C:11](OCC)=[O:12].C1(C)C=CC=CC=1.[H-].C([Al+]CC(C)C)C(C)C.Cl.CC(OI1(OC(C)=O)(OC(C)=O)OC(=O)C2C=CC=CC1=2)=O.S([O-])([O-])=O.[Na+].[Na+]>O1CCCC1.ClCCl>[CH3:1][C:2]1[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[O:4][C:3]=1[CH:11]=[O:12]

Participants

8

Reactant 5

HCID 313Hydrochloric AcidHCID 24437Sodium SulfiteHCID 159087TriacetoxyperiodinaneHCID 1208056Ethyl 3-methyl-1-benzofuran-2-carboxylateHCID 86583787Diisobutylaluminumhydride toluene

Product 1

HCID 1369382-Benzofurancarboxaldehyde, 3-methyl-Yield 48%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolventHCID 8028TetrahydrofuranSolvent

Procedure

To a solution (40 mL) of ethyl 3-methyl-1-benzofuran-2-carboxylate (2.00 g) in tetrahydrofuran was added dropwise 1.5M diisobutylaluminum hydride toluene solution (19.6 mL) at 0° C., and the mixture was stirred for 2 hr. 1N Hydrochloric acid was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure to give a white solid. To a solution (40 mL) of the obtained solid in dichloromethane was added Dess-Martin periodinane (4.96 g) at 0° C., and the mixture was stirred at room temperature overnight. Saturated sodium sulfite aqueous solution was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:9, volume ratio) to give the title object compound (753 mg, 48%) as a white solid.

Workup

  1. customto quench
  2. customthe reaction
  3. extractionthe mixture was extracted with ethyl acetate
  4. washThe extract was washed with saturated brine
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated under reduced pressure
  7. customto give a white solid
  8. stirringthe mixture was stirred at room temperature overnight
  9. customto quench
  10. customthe reaction
  11. extractionthe mixture was extracted with ethyl acetate
  12. washThe extract was washed with saturated aqueous sodium hydrogen carbonate solution and saturated brine
  13. dry with materialdried over magnesium sulfate
  14. concentrationconcentrated under reduced pressure
  15. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:9, volume ratio)

Sources & evidence

ORD record
ord-9938c5c3c940443dba6d2ab343448f3d
Source dataset
uspto-grants-2013_05
Patent number
US08436043B2

Reaction notes

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