反応 #322084

反応方程式

2-amino-5-methoxycarbonylphenol

ethyl acetate

sodium hydrogen carbonate

2-bromohexanoyl bromide

→

2-butyl-7-methoxycarbonyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine

収率 81.7%

溶媒

water

反応条件

後処理

1. 1
   その他The organic layer was separated
2. 2
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
3. 3
   workup.DISSOLUTIONThe resulting residue was dissolved in dimethylformamide (300 ml), to the solution
4. 4
   workup.ADDITIONwas added potassium carbonate (6.0 g)
5. 5
   workup.STIRRINGthe mixture was stirred at room temperature for 1 hour
6. 6
   workup.ADDITIONWater was added to the reaction solution and extraction with ethyl acetate
7. 7
   workup.DISTILLATIONThe solvent was distilled off under reduced pressure
8. 8
   その他the resulting crystals were recrystallized from ether

実験手順

To a solution of 2-amino-5-methoxycarbonylphenol [Tetrahedron, 4.6 (15), 5177-5186 (1990)] (8.0 g) in a mixed solvent of ethyl acetate (200 ml) and water (200 ml) were added sodium hydrogen carbonate (11.18 g) and 2-bromohexanoyl bromide (12.73 g) and the mixture was stirred at room temperature for 10 minutes. The organic layer was separated and the solvent was distilled off under reduced pressure. The resulting residue was dissolved in dimethylformamide (300 ml), to the solution was added potassium carbonate (6.0 g) and the mixture was stirred at room temperature for 1 hour. Water was added to the reaction solution and extraction with ethyl acetate was conducted. The solvent was distilled off under reduced pressure and the resulting crystals were recrystallized from ether to give 2-butyl-7-methoxycarbonyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine (10.3 g).

出典