반응 #674686

반응 방정식

3-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one

CaCl2

→

2-chloro-3-methyl-3H-imidazo[4,5-b]pyridine

용매

phosphorus oxychloride

반응 조건

후처리

1. 1
   추출NaHCO3 at 0° C. and extracted with EtOAc
2. 2
   기타The organic layer was separated
3. 3
   세척washed with water and brine
4. 4
   건조dried over MgSO4
5. 5
   농축concentrated in vacuo
6. 6
   기타The residue was purified by column chromatography (NH silica gel, eluted with 0%-50% EtOAc in hexane)

실험 절차

The mixture of 3-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (1.0 g) in phosphorus oxychloride (10 g) was stirred at 100° C. under a dry atmosphere (CaCl2 tube) for 5 h. The mixture was neutralized with sat.NaHCO3 at 0° C. and extracted with EtOAc. The organic layer was separated, washed with water and brine, dried over MgSO4 and concentrated in vacuo. The residue was purified by column chromatography (NH silica gel, eluted with 0%-50% EtOAc in hexane) to give 2-chloro-3-methyl-3H-imidazo[4,5-b]pyridine (230 mg) as a white solid.

출처