反应详情

3-(4-acetoxymethylindol-3-yl)-2-nitro-4-methoxy-butyric acid ethyl ester (226 g) is hydrogenated in ethanol (2.3 l) with Raney nickel as catalyst under hydrogen of normal pressure without addition of heat. 3 mol of hydrogen is taken up in 31/2 hours, whereby the temperature reaches a maximum of 45° C. After filtering of the catalyst and evaporation of the residue, the raw product is chromatographed on silica gel with a mixture of dichloromethane (97.5%) and ethanol (2.5%). 130 g of the title compound as noncrystalline diastereomeric mixture is obtained.

1. temperatureof heat
2. custom2 hours, whereby
3. customa maximum of 45° C
4. filtrationAfter filtering of the catalyst and evaporation of the residue
5. customthe raw product is chromatographed on silica gel with a mixture of dichloromethane (97.5%) and ethanol (2.5%)