반응 #8318

반응 방정식

ethyl picolinate

ethyl picolinate

lepidine

potassium bis(trimethylsilyl)amide

→

yellow-brown solid

수율 82.0%

1-(2-Pyridyl)-2-(4-quinolyl)ethan-1-one

수율 82.0%

용매

toluene

tetrahydrofuran

반응 조건

후처리

1. 1
   기타In a 3-neck 3-liter round bottom flask equipped with two addition funnels
2. 2
   workup.ADDITIONOne addition funnel
3. 3
   workup.ADDITIONthe base added to the reaction mixture dropwise over 40 min
4. 4
   기타The ice bath is removed
5. 5
   workup.STIRRINGthe reaction mixture stirred at ambient temperature for 3 h
6. 6
   기타The reaction is quenched with water (20 mL) and after 5 min formic acid
7. 7
   workup.ADDITIONadded until the pH
8. 8
   농축The mixture is concentrated in vacuo
9. 9
   기타partitioned between ethyl acetate (300 mL) and brine-sodium bicarbonate (300 mL) mixture
10. 10
    세척The organic layer is washed with brine and sodium bicarbonate
11. 11
    건조dried over sodium sulfate
12. 12
    농축concentrated
13. 13
    기타The product is chromatographed on SiO2 (27-30% acetone in hexane)

실험 절차

In a 3-neck 3-liter round bottom flask equipped with two addition funnels is dissolved lepidine (10.0 mL, 75.63 mmol) in tetrahydrofuran (200 mL). One addition funnel is charged with ethyl picolinate (20.43 mL, 151.26 mmol) and the other with 0.5 M potassium bis(trimethylsilyl)amide (166.4 mL, 83.19 mmol) in toluene. The solution is cooled to −78° C. and the base added to the reaction mixture dropwise over 40 min. The reaction mixture is stirred an additional 1.5 h and ethyl picolinate is added rapidly. The ice bath is removed and the reaction mixture stirred at ambient temperature for 3 h. The reaction is quenched with water (20 mL) and after 5 min formic acid added until the pH is slightly less than 7. The mixture is concentrated in vacuo and partitioned between ethyl acetate (300 mL) and brine-sodium bicarbonate (300 mL) mixture. The organic layer is washed with brine and sodium bicarbonate, dried over sodium sulfate, and concentrated. The product is chromatographed on SiO2 (27-30% acetone in hexane) to yield 15.31 g (82%) of a yellow-brown solid.

출처