反应详情

A solution of methyl E-4-(2-dimethylaminovinyl)-3-nitrobenzoate (5.58 g) in tetrahydrofuran (100 ml) was hydrogenated at 3.45 bar in the presence of 10% (w/w) palladium on carbon (1.1 g) for 35 min. The catalyst was removed by filtration through diatomaceous earth and the filtrate was evaporated. The residue was dissolved in ethyl acetate and the solution obtained was washed successively with 10% (v/v) hydrochloric acid, water, and brine; then dried (MgSO4) and evaporated to give methyl indole-6-carboxylate (3.32 g, 85%) as a white solid; NMR (80 MHz, CDCl3): 3.92(s, 3H, OCH3), 6.57(m, 1H, H3 -indole), 7.32(t, 1H, H2 -indole), 7.10(d, 1H, H4 -indole), 7.87(dd, 1H, H5 -indole), 8.16(broad s, 1H, H7 -indole).

1. customThe catalyst was removed by filtration through diatomaceous earth
2. customthe filtrate was evaporated
3. dissolutionThe residue was dissolved in ethyl acetate
4. customthe solution obtained
5. washwas washed successively with 10% (v/v) hydrochloric acid, water, and brine
6. dry with materialthen dried (MgSO4)
7. customevaporated