Lactic Acid → 6-Fluoro-2-(1-hydroxyethyl)benzoxazole

HRID 369104Notes

Reaction equation

HRID 369104 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([F:8])=[CH:4][C:3]=1[OH:9].[C:10](O)(=O)[CH:11]([CH3:13])[OH:12].C(Cl)Cl>C1(C)C(C)=CC=CC=1>[F:8][C:5]1[CH:6]=[CH:7][C:2]2[N:1]=[C:10]([CH:11]([OH:12])[CH3:13])[O:9][C:3]=2[CH:4]=1

Participants

5

Reactant 3

HCID 612Lactic AcidHCID 6344DichloromethaneHCID 1857632-Amino-5-fluorophenol

Product 1

HCID 232854276-Fluoro-2-(1-hydroxyethyl)benzoxazoleYield 61.2%

Reagents, catalysts & solvents 1

HCID 7237O-XyleneSolvent

Procedure

A suspension of 2-amino-5-fluorophenol (5.50 g, 43.3 mmol) and 85-92% lactic acid (6 g) in xylene was refluxed overnight while removing off water by-produced as a result of the reaction. After replacing the solvent with methylene chloride, the resultant mixture was washed with saturated aqueous sodium bicarbonate, water, and saturated aqueous sodium chloride, dried over magnesium sulfate, and then concentrated. The resulting residue was subjected to recrystallization from a mixture of diisopropyl ether and hexane to afford 6-fluoro-2-(1-hydroxyethyl)benzoxazole (4.80 g, yield: 61%).

Workup

  1. temperaturewas refluxed overnight
  2. customwhile removing off water
  3. customby-produced as
  4. customa result of the reaction
  5. washthe resultant mixture was washed with saturated aqueous sodium bicarbonate, water, and saturated aqueous sodium chloride
  6. dry with materialdried over magnesium sulfate
  7. concentrationconcentrated
  8. customThe resulting residue was subjected to recrystallization from a mixture of diisopropyl ether and hexane

Sources & evidence

ORD record
ord-fdeb2471e6fa422ead0631bde719a62a
Source dataset
uspto-grants-2000_10
Patent number
US06136831

Reaction notes

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