2-Aminophenol → 2-Aminobenzoxazole

HRID 1437443Notes

Reaction equation

HRID 1437443 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[OH:8].C(OCC)(=O)C.[N:15]#[C:16]Br.[OH-].[Na+]>O>[NH2:15][C:16]1[O:8][C:3]2[CH:4]=[CH:5][CH:6]=[CH:7][C:2]=2[N:1]=1

Participants

6

Reactant 4

HCID 58012-AminophenolHCID 8857Ethyl AcetateHCID 10476Cyanogen BromideHCID 14798Sodium Hydroxide

Product 1

HCID 207072-AminobenzoxazoleYield 88.2%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
45 °C

Procedure

A mixture of 2.5 g 2-aminophenol (7-1) and 20 ml ethyl acetate was heated to 45° C. 3 g of cyanogen bromide was added to the mixture. The mixture was stirred at 45-50° C. for 12 hours. After cooling to room temperature, 1.5 g of sodium hydroxide in 15 ml of water was added. The organic layer was separated and washed with brine until neutral pH. Toluene (5 ml) was added and the solvent was removed to yield 2.71 g (88%) 2-aminobenzoxazol (7-2).

Workup

  1. temperatureAfter cooling to room temperature
  2. customThe organic layer was separated
  3. washwashed with brine until neutral pH
  4. additionToluene (5 ml) was added
  5. customthe solvent was removed

Sources & evidence

ORD record
ord-4b01ccef098346269634eae0900a3b84
Source dataset
uspto-grants-2009_11
Patent number
US07622490B2

Reaction notes

Loading…