Methanol → 2-[2-Hydroxy-3-(o-tolylthio)phenyl]propionic acid

HRID 1164113Notes

Reaction equation

HRID 1164113 reaction equation
[C:1]([C:3]([C:10]1[CH:15]=[CH:14][CH:13]=[C:12]([S:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][C:18]=2[CH3:23])[C:11]=1[O:24]C)(C)[C:4]([O:6]CC)=[O:5])#N.I.[OH-].[K+].CO>C(O)(=O)C>[OH:24][C:11]1[C:12]([S:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][C:18]=2[CH3:23])=[CH:13][CH:14]=[CH:15][C:10]=1[CH:3]([CH3:1])[C:4]([OH:6])=[O:5]

Participants

6

Reactant 4

HCID 887MethanolHCID 14797Potassium HydroxideHCID 24841Hydrogen iodideHCID 20513434Ethyl 2-cyano-2-[2-methoxy-3-(o-tolylthio)phenyl]propionate

Product 1

HCID 131394282-[2-Hydroxy-3-(o-tolylthio)phenyl]propionic acidYield 47.5%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

A mixture of ethyl 2-cyano-2-[2-methoxy-3-(o-tolylthio)phenyl]propionate (10 g) and hydriodic acid (58%, 12 ml) in acetic acid (24 ml) was refluxed under heating for 24 hours. After concentration, the residue was dissolved in aqueous sodium hydrogen sulfite and extracted with diethyl ether. The extract was washed with aqueous sodium hydrogen sulfite and water in turn, dried and evaporated under reduced pressure. To the residue was added acetic anhydride (10 ml), and the mixture was refluxed under heating for 10 minutes and evaporated under reduced pressure. The residue was subjected to column chromatography on silica gel (100 g) and eluted with benzene to give oily crude 3-methyl-7-(o-tolylthio)-2,3-dihydrobenzofuran- 2-one (5.4 g). To this product (5.4 g) were added potassium hydroxide (1.5 g) and methanol (50 ml), and the mixture was refluxed under heating for an hour and concentrated under reduced pressure. The residue was crystallized with a mixture of benzene and n-hexane to give 2-[2-hydroxy-3-(o-tolylthio)phenyl]propionic acid (3.85 g), mp. 123°-125° C.

Workup

  1. temperaturewas refluxed
  2. temperatureunder heating for 24 hours
  3. concentrationAfter concentration
  4. dissolutionthe residue was dissolved in aqueous sodium hydrogen sulfite
  5. extractionextracted with diethyl ether
  6. washThe extract was washed with aqueous sodium hydrogen sulfite and water in turn
  7. customdried
  8. customevaporated under reduced pressure
  9. additionTo the residue was added acetic anhydride (10 ml)
  10. temperaturethe mixture was refluxed
  11. temperatureunder heating for 10 minutes
  12. customevaporated under reduced pressure
  13. washeluted with benzene
  14. customto give oily crude 3-methyl-7-(o-tolylthio)-2,3-dihydrobenzofuran- 2-one (5.4 g)
  15. temperaturethe mixture was refluxed
  16. temperatureunder heating for an hour
  17. concentrationconcentrated under reduced pressure
  18. customThe residue was crystallized with a mixture of benzene and n-hexane

Sources & evidence

ORD record
ord-9e1402ba57634a9eb1aaeb60d3d66b7f
Source dataset
uspto-grants-1983_01
Patent number
US04367238

Reaction notes

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