反応 #42496

反応方程式

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

9-BBN

ethanolamine

→

title compound

収率 80.1%

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

収率 80.1%

溶媒

tetrahydrofuran

反応条件

後処理

1. 1
   濃縮the resulting solution was concentrated under reduced pressure
2. 2
   洗浄The residue was washed with hexanes
3. 3
   ろ過filtered
4. 4
   濃縮the filtrate was concentrated under reduced pressure
5. 5
   その他Purification by flash column chromatography (silica, 25% ethyl acetate/hexanes)

実験手順

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.

出典