Water → Tert-butyl 4-(3-amino-4-nitrophenyl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-chloro-2-nitroaniline (5.0 g, 29 mmol), piperazine-1-carboxylic acid tert-butyl ester (17 g, 9.1 mmol) and anhydrous potassium carbonate (4.4 g, 32 mmol) in N,N-dimethylacetamide (20 ml) was stirred at 120° C. under nitrogen for 2 days. Sample NMR analysis showed almost complete conversion of the starting material. The resultant mixture was then cooled to room temperature, poured into cold water (50 mL) and stirred vigorously for 2 hours. The resulting yellow precipitate was collected by filtration, washed well with water then dried on the filter funnel. The resulting yellow brown solid was slurried in diethyl ether, filtered, washed with additional diethylether, dried to afford 4-(3-Amino-4-nitro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (8.0 g, 85.7%) as a yellow powder, and used in the next step without further purification.

Provenance & Evidence