反応 #1016

反応方程式

3,5-Dichloropyridine

LDA

sodium hydrogen carbonate

iodomethane

→

title compound

収率 53.0%

3,5-Dichloro-4-methylpyridine

収率 53.0%

溶媒

THF

THF

dichloromethane

反応条件

後処理

1. 1
   workup.STIRRINGthe reaction mixture stirred for a further 1.5 h at -70° C
2. 2
   その他the organic phase separated
3. 3
   乾燥dried (MgSO4)
4. 4
   濃縮concentrated in vacuo

実験手順

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).

出典