Perchloric Acid → 2,3-Dihydro-4,7-dimethoxy-1H-indene

HRID 1252986Notes

Reaction equation

HRID 1252986 reaction equation
[CH3:1][O:2][C:3]1[CH:11]=[CH:10][C:9]([O:12][CH3:13])=[C:8]2[C:4]=1[CH2:5][CH2:6][C:7]2=O.Cl(O)(=O)(=O)=O.[H][H].C([O-])(=O)C.[K+]>[Pd].C(O)(=O)C>[CH3:13][O:12][C:9]1[CH:10]=[CH:11][C:3]([O:2][CH3:1])=[C:4]2[C:8]=1[CH2:7][CH2:6][CH2:5]2

Participants

7

Reactant 4

HCID 24247Perchloric AcidHCID 517044Potassium AcetateHCID 6060124,7-dimethoxy-2,3-dihydro-1H-inden-1-oneHCID 178418361HCID 178418361, compound

Product 1

HCID 126541332,3-Dihydro-4,7-dimethoxy-1H-indeneYield 48.2%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 176Acetic AcidSolvent

Procedure

A mixture of intermediate A (19 g, 99 mmole), perchloric acid (2.5 ml of a 70% aqueous solution) and 10% palladium on carbon catalyst (2 g) in acetic acid (250 ml) was placed in a Paar bottle and shaken under 40 psi (2.75 bars) of hydrogen in a Paar shaker apparatus for 15 hours. Solid potassium acetate was added, and the mixture was filtered through a Celite pad. The Celite pad was washed with tetrahydrofuran, and the combined filtrates were poured into ice water (2 liters). The resulting white solid was isolated by filtration, washed with water, and dried under vacuum. Chromatography (silica, dichloromethane) afforded the desired product, 4,7-dimethoxyindane (intermediate B) as a white solid (8.5 g). White needles were obtained from ethanol:water (1:1), mp 82°-84°.

Workup

  1. filtrationthe mixture was filtered through a Celite pad
  2. washThe Celite pad was washed with tetrahydrofuran
  3. additionthe combined filtrates were poured into ice water (2 liters)
  4. customThe resulting white solid was isolated by filtration
  5. washwashed with water
  6. customdried under vacuum

Sources & evidence

ORD record
ord-10a2aa633ce24726b677c2fc58c497d2
Source dataset
uspto-grants-1988_05
Patent number
US04746607

Reaction notes

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