methyl 3-(2-amino-5-bromoanilino)-2-methylpropanoate

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

Procedure: Sodium metal (2.4 g, 104 mmol) was added in portions to methanol (50 mL) and the mixture was stirred at room temperature until sodium metal was dissolved completely. The solution was then added dropwise to a cooled solution of methyl 3-(2-amino-5-bromophenylamino)-2-methylpropanoate (6 g, 20.9 mmol) in methanol (100 mL) at 0° C. After addition, the mixture was stirred at room temperature for 12 hours. The mixture was concentrated in vacuo. To the residue was added water (50 mL). The mixture was extracted with ethyl acetate (100 mL×3). The organic layers were combined, dried over anhydrous sodium sulfate and then filtered. The filtrate was concentrated to give a crude product, which was purified by column chromatography (silica-gel, petroleum ether/ethyl acetate=3:1) to afford 7-bromo-3-methyl-4,5-dihydro-1H-benzo[b][1,4]diazepin-2(3H)-one (1.8 g, 34%). was dissolved completely After addition The mixture was concentrated in vacuo To the residue was added water (50 mL) The mixture was extracted with ethyl acetate (100 mL×3) dried over anhydrous sodium sulfate filtered The filtrate was concentrated to give a crude product, which was purified by column chromatography (silica-gel, petroleum ether/ethyl acetate=3:1)

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Iron powder (7 g, 0.12 mol) was added to a mixture of methyl 3-(5-bromo-2-nitrophenylamino)-2-methyl-propanoate (8 g, 25.2 mmol) in the mixed solvents of ammonium chloride aqueous (50 mL) and ethanol (100 mL). Once addition was completed, the mixture was heated to 60° C. for 2 hours. The mixture was filtered. The filtrate was concentrated, diluted with water (100 mL), extracted with ethyl acetate (150 mL×3). The organic layers were separated, combined, dried over anhydrous sodium sulfate, filtered and concentrated to give a residue. The residue was purified by column chromatography (silica gel, petroleum ether/ethyl acetate=3:1) to afford methyl 3-(2-amino-5-bromophenylamino)-2-methylpropanoate (6 g, 83%). Once addition The mixture was filtered The filtrate was concentrated diluted with water (100 mL) extracted with ethyl acetate (150 mL×3) The organic layers were separated dried over anhydrous sodium sulfate filtered concentrated to give a residue The residue was purified by column chromatography (silica gel, petroleum ether/ethyl acetate=3:1)