Yield:745078-74-4 87%

Reaction Conditions:

with hydroxylamine hydrochloride in methanol;

Steps:

2.B 5-(3-Bromo-phenyl)-isoxazole-3-carboxylic Acid Methyl Ester

Example 2B 5-(3-Bromo-phenyl)-isoxazole-3-carboxylic Acid Methyl Ester To a suspension of 2,4-dioxo-4-(3-bromophenyl)-butyric acid methyl ester (10.3 g, 36.1 mmol) in anhydrous MeOH (100 mL) was added hydroxylamine hydrochloride (3.8 g, 54.2 mmol). The mixture was then refluxed for 90 min. The reaction mixture was then cooled to room temperature, and ice/water mixture (200 mL) was added. The mixture was stirred for 20 minutes, filtered through a Buchner funnel and washed with cold water. The light yellow solid was dried in vacuum oven to provide the title compound (8.9 g, 87% yield).

References:

US2004/167188,2004,A1