Anthranilic acid, 3-hydroxy-, methyl ester → Methyl 2-amino-1,3-benzoxazole-4-carboxylate

HRID 249884

Reaction equation

HRID 249884 reaction equation
[N:1]1(C(N2C=CN=C2)N)C=CN=[CH:2]1.[CH3:13][O:14][C:15](=[O:24])[C:16]1[CH:21]=[CH:20][CH:19]=[C:18]([OH:22])[C:17]=1[NH2:23]>C1COCC1.CCOC(C)=O>[NH2:1][C:2]1[O:22][C:18]2[C:17](=[C:16]([C:15]([O:14][CH3:13])=[O:24])[CH:21]=[CH:20][CH:19]=2)[N:23]=1

Participants

5

Reactant 2

HCID 205248Anthranilic acid, 3-hydroxy-, methyl esterHCID 66874404di(1H-imidazole-1-yl)methanamine

Product 1

HCID 66873567Methyl 2-amino-1,3-benzoxazole-4-carboxylateYield 50%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Procedure

To a solution of di (1H-imidazole-1-yl)methanamine (2.05 g, 12.26 mmol) in THF (60 mL) was added methyl-2-amino-3-hydroxybenzoate (1.98 g, 12.26 mmol) at room temperature and the resulting reaction mixture was heated to reflux for 17 h. The reaction mixture was cool to room temperature, diluted with EtOAc (100 mL) and washed with H2O (3×100 mL), saturated ammonium chloride (2×100 mL), dried (Na2SO4), filtered and concentrated under reduced pressure. The crude material was purified by recrystallization from diethyl ether to afford methyl 2-aminobenzoxazole-4-carboxylate (1.10 g, 50%) as a brown solid. 1H NMR and MS consistent.

Workup

  1. customthe resulting reaction mixture
  2. temperaturewas heated
  3. temperatureto reflux for 17 h
  4. washwashed with H2O (3×100 mL), saturated ammonium chloride (2×100 mL)
  5. dry with materialdried (Na2SO4)
  6. filtrationfiltered
  7. concentrationconcentrated under reduced pressure
  8. customThe crude material was purified by recrystallization from diethyl ether

Sources & evidence

ORD record
ord-234bdea1de3a4c6b8789ef4e089ebd36
Source dataset
uspto-grants-2011_01
Patent number
US07863271B2

Linked notes

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