Veratrole → 5,6-Dimethoxy-3-methyl-2,3-dihydro-1H-inden-1-one

HRID 1714450Notes

Reaction equation

HRID 1714450 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[O:9][CH3:10].[C:11](O)(=[O:15])[CH2:12][CH:13]=[CH2:14]>>[CH3:1][O:2][C:3]1[CH:8]=[C:7]2[C:6](=[CH:5][C:4]=1[O:9][CH3:10])[C:11](=[O:15])[CH2:12][CH:13]2[CH3:14]

Participants

3

Reactant 2

HCID 7043Veratrole2×HCID 327433-Butenoic acid2×

Product 1

HCID 6057815,6-Dimethoxy-3-methyl-2,3-dihydro-1H-inden-1-one

Conditions

Temperature
60 °C

Procedure

A mixture of 1,2-dimethoxy-benzene (Compound 47a) (19.1 mL, 0.150 mole) and but-3-enoic acid (Compound 49a) (19.2 mL, 0.225 mole) was stirred under argon in an ice bath. Polyphosphoric acid (230 g, 1.05 mole) was added slowly. After addition was complete, the ice bath was removed and the reaction heated for 16 hours at 60° C. The reaction was added to ice water and extracted with ether. The organic extracts were washed with 3N NaOH, water, brine and dried over Na2SO4. The solvent was then removed in vacuo to yield a yellow solid containing a racemic mixture of the title compounds. The crude material was purified on a silica gel column using 1:2 EtOAc:hexane as the eluents. The pure fractions were combined and concentrated to yield the racemic mixture of the title compound (Intermediate X) as an off-white solid.

Workup

  1. additionAfter addition
  2. customthe ice bath was removed
  3. additionThe reaction was added to ice water
  4. extractionextracted with ether
  5. washThe organic extracts were washed with 3N NaOH, water, brine
  6. dry with materialdried over Na2SO4
  7. customThe solvent was then removed in vacuo
  8. customto yield a yellow solid
  9. additioncontaining
  10. customThe crude material was purified on a silica gel column
  11. concentrationconcentrated
  12. customto yield

Sources & evidence

ORD record
ord-823941352dd14166913f78696a46b1f8
Source dataset
uspto-grants-2010_09
Patent number
US07795440B2

Reaction notes

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