Réaction #42496

Équation de réaction

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

9-BBN

ethanolamine

→

title compound

Rendement 80.1%

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

Rendement 80.1%

Solvants

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   Concentrationthe resulting solution was concentrated under reduced pressure
2. 2
   LavageThe residue was washed with hexanes
3. 3
   Filtrationfiltered
4. 4
   Concentrationthe filtrate was concentrated under reduced pressure
5. 5
   AutrePurification by flash column chromatography (silica, 25% ethyl acetate/hexanes)

Mode opératoire

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.

Source