Реакция #42496

Уравнение реакции

methyl 4-butyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

9-BBN

ethanolamine

→

title compound

Выход 80.1%

Methyl 4-butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

Выход 80.1%

Растворители

tetrahydrofuran

Условия реакции

Обработка

1. 1
   Концентрированиеthe resulting solution was concentrated under reduced pressure
2. 2
   ПромывкаThe residue was washed with hexanes
3. 3
   Фильтрацияfiltered
4. 4
   Концентрированиеthe filtrate was concentrated under reduced pressure
5. 5
   ДругоеPurification by flash column chromatography (silica, 25% ethyl acetate/hexanes)

Методика

A solution of methyl 4-butyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate (800 mg) and 9-BBN (1.6 g) in tetrahydrofuran (13 mL) was refluxed for 1.5 h. The mixture was cooled to room temperature, ethanolamine (0.4 mL) was added, and the resulting solution was concentrated under reduced pressure. The residue was washed with hexanes, filtered, and the filtrate was concentrated under reduced pressure. Purification by flash column chromatography (silica, 25% ethyl acetate/hexanes) afforded 607 mg of the title compound: 1H NMR (300 MHz, DMSO-d6) δ 7.21, 7.16, 6.75, 4.24-4.21, 3.78, 3.34-3.24, 1.55-1.47, 1.38-1.30, 0.95-0.90.

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