Water → ethyl 5-(2-methoxyethoxy)-7-nitro-1H-indole-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl 2-{[4-(2-methoxyethoxy)-2-nitrophenyl]hydrazono}propanoate (250 mg) and polyphosphoric acid (2.0 g) was stirred at 110° C. for 1 hr. After cooling, water and ethyl acetate were added to the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4), and concentrated. The obtained residue was subjected to basic silica gel column chromatography, and eluted with hexane-ethyl acetate (4:1-2:1, volume ratio) to give the title compound (40 mg, yield 17%) as yellow crystals. The crystals were recrystallized from ethyl acetate-hexane to give yellow prism crystals. melting point 90-91° C.

Provenance & Evidence