반응 #169357

반응 방정식

Cesium carbonate

2-bromo-5-chloropyridine

diethyl malonate

picolinic acid

→

title compound

수율 54.0%

Ethyl (5-chloropyridin-2-yl)acetate

수율 54.0%

용매

1,4-dioxane

반응 조건

후처리

1. 1
   기타the solution was degassed with argon for 30 minutes
2. 2
   온도The mixture was cooled to room temperature
3. 3
   기타quenched with water (100 mL)
4. 4
   추출extracted with EtOAc (3×100 ml)
5. 5
   세척The organic extracts were washed with water (200 mL), brine (200 mL)
6. 6
   건조dried over sodium sulfate
7. 7
   기타evaporated in vacuo
8. 8
   기타The residue was purified by column chromatography on silica gel (EtOAc:Hexane 92:8)

실험 절차

Cesium carbonate (71 g, 218 mmol) was added to 2-bromo-5-chloropyridine (14 g, 73 mmol) and diethyl malonate (22 mL, 145 mmol) in dry 1,4-dioxane (280 mL) and the solution was degassed with argon for 30 minutes. Then copper (I) oxide (2.8 g, 14.55 mmol) and picolinic acid (3.6 g, 29 mmol) were added and the mixture was stirred in a sealed vessel at 130° C. for 24 hours. The mixture was cooled to room temperature, quenched with water (100 mL) and extracted with EtOAc (3×100 ml). The organic extracts were washed with water (200 mL), brine (200 mL), dried over sodium sulfate and evaporated in vacuo. The residue was purified by column chromatography on silica gel (EtOAc:Hexane 92:8) to afford the title compound as a yellow oil in 54% yield, 8.0 g.

출처