Hydroxyamine hydrochloride → 5-(4-Bromo-3-methyl-phenyl)-3-methyl-isoxazole-4-carboxylic acid methyl ester
Reaction equation
[CH3:1][O:2][C:3](=[O:19])[CH:4]([C:9](=[O:18])[C:10]1[CH:15]=[CH:14][C:13]([Br:16])=[C:12]([CH3:17])[CH:11]=1)/[C:5](=[N:7]/C)/[CH3:6].Cl.NO>C(O)(=O)C>[CH3:1][O:2][C:3]([C:4]1[C:5]([CH3:6])=[N:7][O:18][C:9]=1[C:10]1[CH:15]=[CH:14][C:13]([Br:16])=[C:12]([CH3:17])[CH:11]=1)=[O:19]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 60 °C
Procedure
2-(4-Bromo-3-methyl-benzoyl)-3-[(E)-methylimino]-butyric acid methyl ester (40.0 mmol) and hydroxylamine hydrochloride (2.9 g, 41 mmol) were combined in acetic acid (100 mL) and stirred at 60° C. overnight. The mixture was concentrated, and the residue was partitioned between EtOAc and water. Saturated aqueous NaHCO3 was added to neutralize residual acetic acid, and the organic layer was separated and washed twice with water. The combined aqueous layers were back-extracted with EtOAc, and the combined organic layers were dried, filtered, and concentrated. The crude material was purified by silica gel chromatography to give the title compound.