Potassium Carbonate → Tert-butyl 4-(3-methoxy-4-nitrophenyl)piperazine-1-carboxylate

Participants

Reaction Steps

A mixture of 5-fluoro-2-nitroanisole (3.00 g, 17.5 mmol), tert-butyl piperazine-1-carboxylate (4.57 g, 24.5 mmol) and potassium carbonate (3.63 g, 26.3 mmol), in dimethyl sulfoxide (20 mL) was heated at 90° C. for 1.5 hours under a nitrogen atmosphere. The reaction mixture was cooled and diluted with water (100 mL). The resulting precipitate was filtered and dried to give a bright yellow solid. The solid was suspended in a 5:1 solution of petroleum ether/diethyl ether (50 mL), sonicated for 2 minutes, filtered and dried to give the title compound (I1) (3.95 g, 66%) as a bright yellow solid; 1H NMR (300 MHz, d6-DMSO) δ 1.42 (s, 9H), 3.46 (brs, 8H), 3.90 (s, 3H), 6.52 (s, 1H), 6.57 (d, 1H, J=9.5 Hz) and 7.89 (d, 1H, J=9.3 Hz). LCMS Method B: rt 7.45 min; m/z 338.2 [M+H]+.

Provenance & Evidence