Reacción #1016

Ecuación de reacción

3,5-Dichloropyridine

LDA

sodium hydrogen carbonate

iodomethane

→

title compound

Rendimiento 53.0%

3,5-Dichloro-4-methylpyridine

Rendimiento 53.0%

Disolventes

THF

THF

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGthe reaction mixture stirred for a further 1.5 h at -70° C
2. 2
   Otrothe organic phase separated
3. 3
   Secadodried (MgSO4)
4. 4
   Concentraciónconcentrated in vacuo

Procedimiento

3,5-Dichloropyridine (2.04 g, 13.5 mmol) in THF (5 ml) was added dropwise to a solution of LDA [prepared from diisopropylamine (1.9 ml, 13.5 mmol) and n-butyllithium (1.6M, 8.4 ml, 13.5 mmol)] in THF (25 ml) at -70° C. After stirring at this temperature for 5 min, iodomethane (0.85 ml, 13.5 mmol) was added and the reaction mixture stirred for a further 1.5 h at -70° C. Saturated sodium hydrogen carbonate solution (20 ml) and dichloromethane (20 ml) was added and the organic phase separated, dried (MgSO4), and concentrated in vacuo. The residue was subjected to chromatography (SiO2 ; Et2O-hexane, 1:3) to afford the title compound (1.16 g) as a pale yellow solid; δH (CDCl3) 2.46 (3H, s, Me), and 8.36 (2H, s, pyridine H2, H6).

Fuente