Methanol → Diethyl formamido[(1H-indol-3-yl)methyl]propanedioate

Participants

Reaction Steps

50.0 g (0.13 mol) of the compound of Example 4 in 500 ml. of methanol and 1 ml of acetic acid was hydrogenated in a rocking autoclave at room temperature and 200 psi in the presence of 6 g. of Raney nickel. After the hydrogen uptake (3 equivalents) was complete the filtered reaction mixture was concentrated in vacuo to a volume of 140 ml. Toluene (600 ml.) was added and the remaining methanol was removed by azeotropic distillation. The mixture was heated at reflux for an additional 30 minutes and then allowed to cool to room temperature. The precipitate was collected, washed with toluene and dried to yield 42.3 g (97%) of white crystals, m.p. 179-180° (lit. m.p. 179°). The analytical sample was prepared by recrystallization from ethaniol: m.p. 180-181°.

Provenance & Evidence