反应详情

A saturated aqueous solution of NH4Cl (99 mL) was added to a solution of 3-chloro-1-(4-methoxy-benzyl)-5-nitro-1H-pyridin-2-one (Step O5) (6.8 g, 23.0 mmol) in EtOH (300 mL). After stirring for 15 min, iron powder (6.4 g, 115 mmol) was added and the resulting mixture was heated to reflux, stirred for 1 h, cooled to rt and concentrated. The residue was diluted with EtOH and the mixture was filtered through a pad of celite. The filtrate was concentrated. The residue was purified by silica gel column chromatography (CH2Cl2/MeOH, 100:0→96.5:3.5). ESI-MS: tR=0.61 min, [M+H]+ 265/267 (LC-MS 1); Rf=0.53 (9:1 CH2Cl2/MeOH).

1. temperaturethe resulting mixture was heated
2. temperatureto reflux
3. stirringstirred for 1 h
4. concentrationconcentrated
5. additionThe residue was diluted with EtOH
6. filtrationthe mixture was filtered through a pad of celite
7. concentrationThe filtrate was concentrated
8. customThe residue was purified by silica gel column chromatography (CH2Cl2/MeOH, 100:0→96.5:3.5)