Реакция #416778

Уравнение реакции

N-isopropylhydroxylamine hydrochloride

sodium hydroxide

2,4-dibromobutyrylchloride

sodium hydroxide

→

dihydro-4-bromo-2-isopropyl-2H-1,2-oxazin-3(4H)-one

Выход 10.5%

Растворители

methylene chloride

water

Условия реакции

Обработка

1. 1
   workup.ADDITIONTo this mixture was added
2. 2
   workup.ADDITIONwas added
3. 3
   ДругоеAfter twenty hours the organic phase was separated
4. 4
   Сушкаdried over anhydrous magnesium sulfate
5. 5
   Концентрированиеconcentrated to an oil
6. 6
   ДругоеThis oil was chromatographed on silica gel with 40% ethyl acetate-hexane

Методика

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.

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