Ethyl chloronicotinate → Ethyl 2-ethylnicotinate

温度

70 °C

To a solution of ethyl 2-chloropyridine-3-carboxylate (15 g, 81 mmol) in anhydrous 1,4-dioxane (150 mL) at room temperature was added (1,1′-bis(diphenylphosphino)ferrocene)dichloropalladium (II) (1.3 g, 1.6 mmol) followed by a diethylzinc solution (75 mL, 83 mmol, 1.1 M solution in toluene). The mixture was stirred at 70° C. for 1 hour. After cooling to room temperature, the reaction was quenched with MeOH. Ethyl acetate (200 mL) was added. The mixture was extracted with 0.2 N HCl (200 mL). The organic layer was recovered. The pH of the aqueous phase was brought around 6 with 2 N NaOH. The mixture was extracted with EtOAc (1×100 mL). The combined organic extracts were dried over MgSO4, filtered, evaporated, and dried in vacuo. The crude product was purified by flash chromatography (0-20% ethyl acetate/hexane), affording ethyl 2-ethylpyridine-3-carboxylate (8.8 g, 61% yield)

1. temperatureAfter cooling to room temperature
2. customthe reaction was quenched with MeOH
3. additionEthyl acetate (200 mL) was added
4. extractionThe mixture was extracted with 0.2 N HCl (200 mL)
5. customThe organic layer was recovered
6. extractionThe mixture was extracted with EtOAc (1×100 mL)
7. dry with materialThe combined organic extracts were dried over MgSO4
8. filtrationfiltered
9. customevaporated
10. customdried in vacuo
11. customThe crude product was purified by flash chromatography (0-20% ethyl acetate/hexane)

ORDレコード

ord-3862b1f8b7ef4b27ae9b6e4be2c8bbb4

出典データセット

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US09315521B2