methyl 2,4-dioxo-4-phenylbutanoate

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

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

Procedure: 983 mg hydrazine acetate was added to 2 g 2,4-Dioxo-4-phenyl-butyric acid methyl ester in 10 mL concentrated acetic acid. The mixture was stirred over night at RT. Then water was added. The precipitate was filtered, stirred with diisopropylether and again filtered to give 1.3 g desired product. Rt: 1.39 min (method O), (M+H)+: 203 The precipitate was filtered stirred with diisopropylether again filtered

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

Procedure: 983 mg hydrazine acetate was added to 2 g 2,4-Dioxo-4-phenyl-butyric acid methyl ester in 10 mL concentrated acetic acid. The mixture was stirred over night at RT. Then water was added. The precipitate was filtered, stirred with diisopropylether and again filtered to give 1.3 g desired product. Rt: 1.39 min (method O), (M+H)+: 203 The precipitate was filtered stirred with diisopropylether again filtered

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

Procedure: 983 mg hydrazine acetate was added to 2 g 2,4-Dioxo-4-phenyl-butyric acid methyl ester in 10 mL concentrated acetic acid. The mixture was stirred over night at RT. Then water was added. The precipitate was filtered, stirred with diisopropylether and again filtered to give 1.3 g desired product. Rt: 1.39 min (method O), (M+H)+: 203 The precipitate was filtered stirred with diisopropylether again filtered

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

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

Procedure: Methyl 4-phenyl-2,4-dioxobutanoate (10 g) obtained by acetophenone and dimethyl oxalate as starting materials and methylhydrazine were reacted in ethanol (60 ml) at a refluxing temperature for 1 h. The solvent was evaporated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (mobile phase:dichloromethane) to give methyl 1-methyl-3-phenylpyrazole-5-carboxylate (3.0 g) and methyl 1-methyl-5-phenylpyrazole-3-carboxylate (3.6 g).

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

Procedure: 983 mg hydrazine acetate was added to 2 g 2,4-Dioxo-4-phenyl-butyric acid methyl ester in 10 mL concentrated acetic acid. The mixture was stirred over night at RT. Then water was added. The precipitate was filtered, stirred with diisopropylether and again filtered to give 1.3 g desired product. Rt: 1.39 min (method O), (M+H)+: 203 The precipitate was filtered stirred with diisopropylether again filtered