反应详情

Concentrated sulphuric acid (110 ml) and concentrated nitric acid (19.0 ml, 0.289 mol) were added cautiously, over a 50 minute period, to a two-phase system containing a stirred solution of ethyl 3-methoxy-4-(3-morpholinopropoxy)benzoate (76.5 g, 0.237 mol) in dichloromethane (600 ml), acetic acid (300 ml) and water (70 ml) at 5° C. The reaction was allowed to warm to ambient temperature over 18 hours, the aqueous phase was separated, and the aqueous phase was taken to pH 9 by addition of 40% aqueous sodium hydroxide solution (775 ml). Extraction of the aqueous phase with dichloromethane (3×600 ml) and subsequent solvent evaporation in vacuo_yielded ethyl 3-methoxy-4-(3-morpholinopropoxy)-6-nitrobenzoate (141.3 g, 86% yield) as a yellow gum:

1. customthe aqueous phase was separated
2. additionthe aqueous phase was taken to pH 9 by addition of 40% aqueous sodium hydroxide solution (775 ml)
3. extractionExtraction of the aqueous phase