反応 #42470

反応方程式

Methyl 3-bromo-5-(butylamino)-4-methoxybenzoate

BBr3

→

title compound

収率 88.5%

Methyl 3-bromo-5-(butylamino)-4-hydroxybenzoate

収率 88.5%

溶媒

methylene chloride

反応条件

後処理

1. 1
   濃縮The mixture was concentrated under reduced pressure
2. 2
   workup.DISSOLUTIONthe residue was dissolved in methylene chloride
3. 3
   workup.ADDITIONsaturated sodium bicarbonate was added
4. 4
   workup.ADDITIONmethanol was added dropwise
5. 5
   workup.STIRRINGAfter stirring for 30 min
6. 6
   workup.STIRRINGthe mixture was stirred at room temperature for 1 h
7. 7
   その他The solvent was removed
8. 8
   workup.DISSOLUTIONthe residue dissolved in methylene chloride
9. 9
   洗浄washed with water, saturated sodium bicarbonate (15 mL), and brine
10. 10
    乾燥dried (magnesium sulfate)
11. 11
    ろ過filtered
12. 12
    濃縮concentrated under reduced pressure
13. 13
    その他Purification by flash column chromatography (silica, 1:20, ethyl acetate/hexanes)

実験手順

To a −78° C. solution of the Methyl 3-bromo-5-(butylamino)-4-methoxybenzoate (520 mg) in methylene chloride (10 mL) was added BBr3 (8 ml of 1.0 M solution in methylene chloride) dropwise and the reaction mixture was stirred for 18 h. The mixture was concentrated under reduced pressure, and the residue was dissolved in methylene chloride and saturated sodium bicarbonate was added. The mixture was cooled to 0° C. and methanol was added dropwise. After stirring for 30 min, the mixture was stirred at room temperature for 1 h. The solvent was removed, and the residue dissolved in methylene chloride, washed with water, saturated sodium bicarbonate (15 mL), and brine, dried (magnesium sulfate), filtered, and concentrated under reduced pressure. Purification by flash column chromatography (silica, 1:20, ethyl acetate/hexanes) provided 440 mg of the title compound: 1H NMR (300 MHz, CDCl3) δ 7.52, 7.19, 3.88, 3.18, 1.65, 1.46, 0.97.

出典