反応 #63725

反応方程式

sodium bicarbonate

2,3-dimethylpyridine 1-oxide

trichloroacetyl chloride

→

2-chloromethyl-3-methylpyridine

溶媒

chloroform

反応条件

後処理

1. 1
   温度at reflux
2. 2
   温度The reaction mixture is heated
3. 3
   温度under reflux for 2.5 hours
4. 4
   洗浄the resulting solution is washed several times with methylene chloride
5. 5
   乾燥The organic phase is dried with sodium sulphate
6. 6
   ろ過filtered
7. 7
   濃縮concentrated
8. 8
   その他The residue is chromatographed on silica gel with methylene chloride
9. 9
   その他the pressure being produced with nitrogen gas

実験手順

A solution of 15 g (0.12 mol) of 2,3-dimethylpyridine 1-oxide in 75 ml of chloroform is boiled at reflux and treated as rapidly as possible with 37 ml of trichloroacetyl chloride (it is advantageous to add the acid chloride through the reflux condenser). The reaction mixture is heated under reflux for 2.5 hours, subsequently poured into a mixture of ice and sodium bicarbonate and the resulting solution is washed several times with methylene chloride. The organic phase is dried with sodium sulphate, filtered and concentrated. The residue is chromatographed on silica gel with methylene chloride, the medium pressure flash chromatography method being used and the pressure being produced with nitrogen gas. The 2-chloromethyl-3-methylpyridine obtained is processed directly.

出典