反应详情

A solution of (4-nitro-2-methyl-1H-indol-1-yl)-acetic acid, ethyl ester (5.0 g, 19 mmol) in ethyl acetate (75 ml) was hydrogenated under 3 bar hydrogen pressure in the presence of a wet 1% Pt/C catalyst paste (38 w/w, 0.7 g) until hydrogen uptake ceased (3 hours). The reaction mixture was filtered through kieselguhr and the solids washed with ethyl acetate (75 ml). The filtrate and wash were combined with solutions obtained from 2 previous experiments which had been carried out in a similar maimer, each on a 2 g scale, and evaporated to dryness to provide (4-amino-2-methyl-1H-indol-1-yl)-acetic acid, ethyl ester, 8.59 g, >100% as a brown oil which solidified on standing.

1. custom(3 hours)
2. filtrationThe reaction mixture was filtered through kieselguhr
3. washthe solids washed with ethyl acetate (75 ml)
4. washThe filtrate and wash
5. customobtained from 2 previous experiments which
6. customeach on a 2 g scale, and evaporated to dryness