反应详情

温度

5 °C

To a stirred mixture of 5.3 g (47 mmol) of N-isopropylhydroxylamine hydrochloride in 100 ml of methylene chloride cooled to 5° C. was added 3.8 g (47 mmol) of 50% sodium hydroxide solution in 20 ml of water. To this mixture was added with stirring 12.4 g (47 mmol) of 2,4-dibromobutyrylchloride and twenty minutes later an additional 7.6 g (94 mmol) of 50% sodium hydroxide solution was added. After twenty hours the organic phase was separated, dried over anhydrous magnesium sulfate and concentrated to an oil. This oil was chromatographed on silica gel with 40% ethyl acetate-hexane to afford 1.1 g of oily dihydro-4-bromo-2-isopropyl-2H-1,2-oxazin-3(4H)-one.

1. additionTo this mixture was added
2. additionwas added
3. customAfter twenty hours the organic phase was separated
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated to an oil
6. customThis oil was chromatographed on silica gel with 40% ethyl acetate-hexane