N'-phenylacetohydrazide

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: To a solution of 1-acetyl-2-phenylhydrazine (2 g, 13.3 mmol) in anhydrous toluene 20 ml was added bromoethanol (1.04 ml, 14.6 mmol), diisopropylethylamine (2.54 ml, 14.6 ml) at room temperature. The reaction mixture was refluxed under nitrogen for 40 hours. After cooling, the reaction was then quenched with 100 ml water, extracted with dichloromethane 2×100 ml. The organic was dried (MgSO4) and removed in vacuo. The residue was purified by flash column chromatography over silica using a gradient 50% mixture of ethyl acetate and hexane to 100% ethyl acetate as eluant. Appropriate fractions were combined and the solvent was removed in vacuo to give the product as a yellow oil 0.9 g (Yield 35%). The reaction mixture was refluxed under nitrogen for 40 hours After cooling the reaction was then quenched with 100 ml water extracted with dichloromethane 2×100 ml The organic was dried (MgSO4) removed in vacuo The residue was purified by flash column chromatography over silica using a gradient 50% mixture of ethyl acetate and hexane to 100% ethyl acetate as eluant the solvent was removed in vacuo

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 5.7-g (0.1-mol) sample of methyl isocyanate was added dropwise to a solution of 15.0 g (0.1 mol) 1-acetyl-2-phenyl-hydrazine and 2 drops triethylamine in 200 ml dichloromethane. The resulting reaction mixture was stirred for 2 hours at about 25° C., refluxed for about 16 hours and evaporated under reduced pressure to give 21 g of crude 1-acetyl-2-phenyl-4-methyl semicarbazide, as a yellow solid. The resulting reaction mixture refluxed for about 16 hours evaporated under reduced pressure