p-Toluenesulfonic acid → Methyl 3,5-dihydroxy-4-methylbenzoate

HRID 555167Notes

Reaction equation

HRID 555167 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([OH:12])[C:10]=1[CH3:11])[C:5]([OH:7])=[O:6].[CH3:13]C1C=CC(S(O)(=O)=O)=CC=1>CO>[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([OH:12])[C:10]=1[CH3:11])[C:5]([O:7][CH3:13])=[O:6]

Participants

4

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 27480453,5-Dihydroxy-4-methylbenzoic Acid

Product 1

HCID 11458051Methyl 3,5-dihydroxy-4-methylbenzoate

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

3,5-Dihydroxy-4-methylbenzoic acid (5.0 g, 29.79 mmol, 1.0 eq) and PTSA (1.13 g, 5.94 mmol, 0.2 eq) were dissolved in 50 ml of methanol, and the mixture was heated to reflux for 6 h. Methanol was evaporated. The resultant solid was washed with 10% sodium bicarbonate solution. The aqueous solution was extracted thrice with ethyl acetate. The combined organic layer was dried over sodium sulphate and evaporated under vacuum. Yield: 5.25 g (96%). 1H NMR (400 MHz, DMSO-d6): δ 1.98 (s, 3H), 3.78 (s, 3H), 6.93 (s, 2H), 9.53 (s, 2H). LCMS: (ES+) m/z=183 (M+H) Method: Column: PHENOMENEX® Luna C18 (4.6×30) mm, 5 micron. Mphase A: 10% MeOH-90% H2O-10 mM NH4OAc. Mphase B: 90% MeOH-10% H2O-10 mM NH4OAc. Flow: 5 ml/min

Workup

  1. temperaturethe mixture was heated
  2. temperatureto reflux for 6 h
  3. customMethanol was evaporated
  4. washThe resultant solid was washed with 10% sodium bicarbonate solution
  5. extractionThe aqueous solution was extracted thrice with ethyl acetate
  6. dry with materialThe combined organic layer was dried over sodium sulphate
  7. customevaporated under vacuum

Sources & evidence

ORD record
ord-f13df86490824119ad650454f82e7374
Source dataset
uspto-grants-2011_11
Patent number
US08048887B2

Reaction notes

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