Hydrochloric Acid → (RS)-3,4-dihydroxy-6-methoxy-7-methyl-1,3-dihydro-isobenzofuran-1-one

HRID 234205Notes

Reaction equation

HRID 234205 reaction equation
[OH-].[K+].C[O:4][C:5](=[O:18])[C:6]1[C:11]([CH3:12])=[C:10]([O:13][CH3:14])[CH:9]=[C:8]([OH:15])[C:7]=1[CH:16]=[O:17].Cl>O>[OH:17][CH:16]1[C:7]2[C:6](=[C:11]([CH3:12])[C:10]([O:13][CH3:14])=[CH:9][C:8]=2[OH:15])[C:5](=[O:18])[O:4]1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 14797Potassium HydroxideHCID 53881817HCID 53881817, compound

Product 1

HCID 11160120(RS)-3,4-dihydroxy-6-methoxy-7-methyl-1,3-dihydro-isobenzofuran-1-oneYield 98.1%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
75 °C

Procedure

A solution of 28 g of potassium hydroxide in 0.2 l of water was added to 44.8 g of 2-formyl-3-hydroxy-5-methoxy-6-methylbenzoic acid methyl ester. The mixture was warmed to 75° C. within 30 rain and subsequently cooled to 5° C. Upon addition of 50 ml of 10N hydrochloric acid, a precipitate was formed immediately. The mixture was stirred at 0° C. for 30 rain and then filtered. The solid material was washed with water and dried in vacuo. The crude product was triturated with 160 ml of hot ethyl acetate. The mixture was cooled and 0.9 l of hexane were added. The solid was isolated by filtration to yield 41.2 g of (RS)-3,4-dihydroxy-6-methoxy-7-methyl-1,3-dihydro-iso-benzofuran-1-one, m.p. >255° C. (dec.).

Workup

  1. temperaturesubsequently cooled to 5° C
  2. customa precipitate was formed immediately
  3. filtrationfiltered
  4. washThe solid material was washed with water
  5. customdried in vacuo
  6. customThe crude product was triturated with 160 ml of hot ethyl acetate
  7. temperatureThe mixture was cooled
  8. addition0.9 l of hexane were added
  9. customThe solid was isolated by filtration

Sources & evidence

ORD record
ord-58812922c9e247d3ad1e7f940fcf403b
Source dataset
uspto-grants-1997_01
Patent number
US05594135

Reaction notes

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