methyl 4-(2-aminophenyl)-4-oxobutanoate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 4.87 g (23.73 mM) of methyl 4-(2-aminophenyl)-4-oxo-2-butenoate in 120 ml of methanol and 6 ml of water is hydrogenated in the presence of 974 mg of 10% Pd-C at room temperature under atmospheric pressure. After removal of the catalyst, the mixture is concentrated to give a residue, which is chromatographed on a column of silica gel (274 g), eluting with toluene-ethyl acetate (30:1-19:1 v/v) to give 3.746 g of methyl 4-(2-aminophenyl)-4-oxobutyrate as orange crystals. This is recrystallized from Et2O-n-hexane to give 3.162 g (Yield: 64.3%) melting at 50.0°-51.0° C. as yellow crystals. After removal of the catalyst the mixture is concentrated to give a residue, which is chromatographed on a column of silica gel (274 g) eluting with toluene-ethyl acetate (30:1-19:1 v/v)