반응 #169785

반응 방정식

CaCl2

tert-butyl (2,5-dichloropyridin-3-yl)carbamate

4-(benzyloxy)aniline

9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene

sodium tert-butoxide

NaH

ethyl iodide

→

3-[4-(benzyloxy)phenyl]-6-chloro-1-ethyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one

용매

toluene

2-propanol

MeOH

DMF

반응 조건

후처리

1. 1
   농축The reaction mixture was concentrated in vacuo
2. 2
   기타The residue was purified by column chromatography (silica gel, eluted with 0%-100% EtOAc in hexane)
3. 3
   기타to give intermediate
4. 4
   농축concentrated in vacuo
5. 5
   기타The residue was purified by column chromatography (NH silica gel, eluted with 0%-50% EtOAc in hexane)

실험 절차

The mixture of tert-butyl (2,5-dichloropyridin-3-yl)carbamate (7.0 g), 4-(benzyloxy)aniline (7.95 g), 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene (1.231 g), Pd2(dba)3 (0.974 g) and sodium tert-butoxide (3.58 g) in toluene (160 ml)-2-propanol (40.0 mL) was stirred at 100° C. under Ar overnight. The reaction mixture was concentrated in vacuo. The residue was purified by column chromatography (silica gel, eluted with 0%-100% EtOAc in hexane) to give intermediate. To the intermediate in DMF (100 mL) were added NaH (3.19 g) and ethyl iodide (20.75 g). The mixture was stirred at room temperature under a dry atmosphere (CaCl2 tube) for 1 h. The reaction mixture was diluted with MeOH and concentrated in vacuo. The residue was purified by column chromatography (NH silica gel, eluted with 0%-50% EtOAc in hexane) to give 3-[4-(benzyloxy)phenyl]-6-chloro-1-ethyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (2 g) as a colorless solid.

출처