Nitric Acid → 6-Amino-5-methyl-1,3-benzoxazol-2(3H)-one

HRID 1262397Notes

Reaction equation

HRID 1262397 reaction equation
[CH3:1][C:2]1[CH:3]=[CH:4][C:5]2[O:9][C:8](=[O:10])[NH:7][C:6]=2[CH:11]=1.[N+:12]([O-])(O)=O>[Pd].CO>[NH2:12][C:3]1[C:2]([CH3:1])=[CH:11][C:6]2[NH:7][C:8](=[O:10])[O:9][C:5]=2[CH:4]=1

Participants

5

Reactant 2

HCID 944Nitric AcidHCID 3226325-methyl-1,3-benzoxazol-2(3H)-one

Product 1

HCID 189704806-Amino-5-methyl-1,3-benzoxazol-2(3H)-oneYield 63.2%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Conditions

Temperature
50 °C

Procedure

5-Methyl-3H-benzoxazol-2-one (1.10 g, 7.38 mmol) added to stirring Nitric acid (6.00 mL, 143 mmol). After stirring 1 h, the mixture was heated at 50° C. for 4 h, cooled and then poured into 100 mL ice and allowed to stand overnight to melt. The yellow solids were collected by filtration, washing with water. The crude nitro product was hydrogenated (25 psi) over 10% Palladium on Carbon (50% Wet) (0.240 g, 0.113 mmol) in Methanol (30.0 mL) for 3 h. The mixture was filtered through Celite and rinsed with MeOH (50 mL). After conc. in vacuo, 6-Amino-5-methyl-3H-benzoxazol-2-one (0.765 g; Yield=63.2%) was isolated as an off-white solid.

Workup

  1. temperaturecooled
  2. waitto stand overnight
  3. filtrationThe yellow solids were collected by filtration
  4. washwashing with water
  5. customfor 3 h
  6. filtrationThe mixture was filtered through Celite
  7. washrinsed with MeOH (50 mL)

Sources & evidence

ORD record
ord-94eff0df4dcf4b1fb89153bce478f47d
Source dataset
uspto-grants-2013_06
Patent number
US08471005B2

Reaction notes

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