反应详情

A mixture of 0.600 g of 2-chloro-3-nitro-pyridine (Aldrich) and 0.800 g of (4-amino-2-chloro-phenyl)-acetic acid ethyl ester (see WO 97/21665) in 20 ml of EtOH/dioxane (1:1, v/v) is stirred and refluxed for 72 hours. The mixture obtained is allowed to cool to rt and is concentrated in vacuo. The concentrate obtained is subjected to silica gel column chromatography. A solid is obtained which is triturated with Et2O. [2-Chloro-4-(3-nitro-pyridin-2-ylamino)-phenyl]-acetic acid ethyl ester is obtained in the form of a solid. ES-MS: 336.0 [M+H]+; single peak at tR=5.59 min (System 1); Rf=0.39 (Hexane/EtOAc, 7:3).

1. temperaturerefluxed for 72 hours
2. customThe mixture obtained
3. concentrationis concentrated in vacuo
4. customThe concentrate obtained
5. customA solid is obtained which
6. customis triturated with Et2O