反応 #439903

反応方程式

ammonium chloride

methyl 4-bromobenzoate

diethyl-3-pyridylborane

potassium hydroxide

→

title compound

収率 52.8%

Methyl 4-(3-pyridyl)benzoate

収率 52.8%

溶媒

ethyl acetate

tetrahydrofuran

water

反応条件

後処理

1. 1
   温度The resulting mixture was heated
2. 2
   温度under reflux for 2 hours
3. 3
   その他The organic layer so separated
4. 4
   乾燥was dried over anhydrous magnesium sulfate
5. 5
   その他The residue obtained
6. 6
   workup.DISTILLATIONby distilling off the solvent
7. 7
   その他was purified by chromatography on a silica gel column (hexane: ethyl acetate=1:1)
8. 8
   workup.DISTILLATIONThe solvent was then distilled off
9. 9
   workup.ADDITIONTo the residue, methanol and IN aqueous hydrochloric acid in ethanol were added
10. 10
    workup.DISTILLATIONThe solvent was distilled off again
11. 11
    workup.ADDITIONTetrahydrofuran was added to the residue
12. 12
    その他the solid so precipitated
13. 13
    ろ過was collected by filtration
14. 14
    その他After drying

実験手順

In tetrahydrofuran (100 ml), methyl 4-bromobenzoate (5.04 g) and diethyl-3-pyridylborane (Chem. Pharm. Bull., 33, 4755, 1985) (2.30 g) were dissolved, followed by the addition of tetrabutylammonium bromide (2.51 g), potassium hydroxide (2.63 g), tetrakis(triphenylphosphine)palladium (O) (1.8 g) and water (1 ml) under an argon atmosphere. The resulting mixture was heated under reflux for 2 hours. After ice cooling, an aqueous ammonium chloride solution and ethyl acetate were added to the reaction mixture. The organic layer so separated was dried over anhydrous magnesium sulfate. The residue obtained by distilling off the solvent was purified by chromatography on a silica gel column (hexane: ethyl acetate=1:1). The solvent was then distilled off. To the residue, methanol and IN aqueous hydrochloric acid in ethanol were added. The solvent was distilled off again. Tetrahydrofuran was added to the residue and the solid so precipitated was collected by filtration. After drying, the title compound (1.76 g, 45%) was obtained as a colorless solid.

出典