Hydrochloric Acid → 4-Hydroxy-3-methylmandelic acid

HRID 1708257Notes

Reaction equation

HRID 1708257 reaction equation
[C:1]1([CH3:8])[C:6]([OH:7])=[CH:5][CH:4]=[CH:3][CH:2]=1.[C:9]([OH:13])(=[O:12])[CH2:10][OH:11].Cl>[OH-].[Na+]>[OH:7][C:6]1[CH:5]=[CH:4][C:3]([CH:10]([OH:11])[C:9]([OH:13])=[O:12])=[CH:2][C:1]=1[CH3:8]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 335O-CresolHCID 757Glycolic Acid2×

Product 1

HCID 233614054-Hydroxy-3-methylmandelic acidYield 137.7%

Reagents, catalysts & solvents 1

HCID 14798Sodium HydroxideSolvent3×

Procedure

32.4 g (0.30 mol) of o-cresol are dissolved in 150 ml of 2N sodium hydroxide solution under a nitrogen atmosphere. After cooling to +5° C., 4.8 g (0.12 mol) of sodium hydroxide and 13.3 ml (0.12 mol) of 50% aqueous glycolic acid are added, and the reaction mixture is stirred at room temperature for 4 hours. A further 0.12 mol of sodium hydroxide and glycolic acid (a total of 0.36 mol) is added twice after 4 hours each time. The reaction mixture is then stirred for another 12 hours, neutralised with concentrated hydrochloric acid and washed twice with 75 ml of petroleum ether. The aqueous phase is then acidified with concentrated hydrochloric acid and extracted several times with ether. The organic phases are combined, dried over magnesium sulfate and concentrated on a vacuum rotary evaporator, giving 30.1 g (55%) of 4-hydroxy-3-methylmandelic acid, melting point 115°-120° C.

Workup

  1. temperatureAfter cooling to +5° C.
  2. stirringThe reaction mixture is then stirred for another 12 hours
  3. washwashed twice with 75 ml of petroleum ether
  4. extractionextracted several times with ether
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated on a vacuum rotary evaporator

Sources & evidence

ORD record
ord-643e7d49abc34b14b7a42ac8440cf10d
Source dataset
uspto-grants-1994_10
Patent number
US05356966

Reaction notes

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