Reacción #162275

Ecuación de reacción

Methyl 4,6-dichloro-3-iodopicolinate

vinyltributylstannane

→

title compound

Rendimiento 76.0%

methyl 4,6-dichloro-3-vinylpicolinate

Rendimiento 76.0%

Disolventes

1,2-dichloroethane

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothe mixture was sparged with a stream of nitrogen for 15 min
2. 2
   Temperaturaat reflux for 21 h
3. 3
   workup.ADDITIONdiluted with ethyl acetate (15 mL)
4. 4
   workup.ADDITIONA solution of 20% KHF2 (10 ml) was added
5. 5
   workup.STIRRINGthe mixture was stirred for 45 minutes
6. 6
   FiltraciónThe mixture was filtered through Celite
7. 7
   LavadoThe organic phase was washed with water
8. 8
   Lavadowashed with saturated sodium chloride
9. 9
   Secadodried over sodium sulfate
10. 10
    Concentraciónconcentrated under vacuum
11. 11
    OtroThe crude product was purified by flash chromatography (SiO2, ethyl acetate/hexanes)

Procedimiento

Methyl 4,6-dichloro-3-iodopicolinate (0.56 g, 1.7 mmol), vinyltributylstannane (580 μl, 0.63 g, 2.0 mmol) and bis(triphenylphosphine)palladium(II) chloride (0.12 g, 0.17 mmol) were combined in 1,2-dichloroethane (8 mL) and the mixture was sparged with a stream of nitrogen for 15 min. The reaction mixture was stirred at reflux for 21 h, cooled to room temperature, and diluted with ethyl acetate (15 mL). A solution of 20% KHF2 (10 ml) was added and the mixture was stirred for 45 minutes. The mixture was filtered through Celite. The organic phase was washed with water, washed with saturated sodium chloride, dried over sodium sulfate, and concentrated under vacuum. The crude product was purified by flash chromatography (SiO2, ethyl acetate/hexanes) to afford the title compound as a solid (0.30 g, 70%): 1H NMR (400 MHz, CDCl3) δ 7.50 (s, 1H), 6.82 (ddd, J=17.8, 11.5, 1.7 Hz, 1H), 5.66 (dd, J=11.4, 8.1 Hz, 1H), 5.55 (dt, J=17.7, 5.0 Hz, 1H), 3.92 (s, 3H); EIMS m/z 231.

Fuente