Réaction #63725

Équation de réaction

sodium bicarbonate

2,3-dimethylpyridine 1-oxide

trichloroacetyl chloride

→

2-chloromethyl-3-methylpyridine

Solvants

chloroform

Conditions de réaction

Traitement

1. 1
   Températureat reflux
2. 2
   TempératureThe reaction mixture is heated
3. 3
   Températureunder reflux for 2.5 hours
4. 4
   Lavagethe resulting solution is washed several times with methylene chloride
5. 5
   SéchageThe organic phase is dried with sodium sulphate
6. 6
   Filtrationfiltered
7. 7
   Concentrationconcentrated
8. 8
   AutreThe residue is chromatographed on silica gel with methylene chloride
9. 9
   Autrethe pressure being produced with nitrogen gas

Mode opératoire

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.

Source