Reacción #42496

Ecuación de reacción

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

9-BBN

ethanolamine

→

title compound

Rendimiento 80.1%

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

Rendimiento 80.1%

Disolventes

tetrahydrofuran

Condiciones de reacción

Tratamiento posterior

1. 1
   Concentraciónthe resulting solution was concentrated under reduced pressure
2. 2
   LavadoThe residue was washed with hexanes
3. 3
   Filtraciónfiltered
4. 4
   Concentraciónthe filtrate was concentrated under reduced pressure
5. 5
   OtroPurification by flash column chromatography (silica, 25% ethyl acetate/hexanes)

Procedimiento

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.

Fuente