2-Aminophenol → 2,2-dimethyl-3,4-dihydro-2H-1,4-benzoxazin-3-one

HRID 635791Notes

Reaction equation

HRID 635791 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[OH:8].[H-].[Na+].C([O:13][C:14](=O)[C:15](Br)([CH3:17])[CH3:16])C>C1(C)C=CC=CC=1.[Cl-].C([N+](CC)(CC)CC1C=CC=CC=1)C>[CH3:16][C:15]1([CH3:17])[C:14](=[O:13])[NH:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=2[O:8]1

Participants

6

Reactant 3

HCID 58012-AminophenolHCID 11745Propanoic acid, 2-bromo-2-methyl-, ethyl esterHCID 24758Sodium hydride

Product 1

HCID 106073952,2-dimethyl-3,4-dihydro-2H-1,4-benzoxazin-3-one

Reagents, catalysts & solvents 2

HCID 66133Benzyl triethylammonium chlorideCatalystHCID 1140TolueneSolvent

Procedure

3 g of 2-aminophenol is mixed in 23 ml of toluene with 1.8 g of sodium hydride with the addition of 50 mg of TEBA (triethylbenzylammonium chloride), and 4.4 ml of 2-bromo-2-methylpropionic acid ethyl ester is added drop by drop at ice bath temperature. After 2 hours at room temperature, it is poured onto ice water, extracted with ethyl acetate, washed with brine, the organic phase is dried with magnesium sulfate and concentrated by evaporation. After recrystallization from isopropyl ether, 278 mg of crystals results.

Workup

  1. additionis added drop by drop at ice bath temperature
  2. additionit is poured onto ice water
  3. extractionextracted with ethyl acetate
  4. washwashed with brine
  5. dry with materialthe organic phase is dried with magnesium sulfate
  6. concentrationconcentrated by evaporation
  7. customAfter recrystallization from isopropyl ether, 278 mg of crystals
  8. customresults

Sources & evidence

ORD record
ord-b21f562c13d44f9aaf28a96bc0a9bde9
Source dataset
uspto-grants-2001_02
Patent number
US06191127B1

Reaction notes

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