Dimethyl Sulfoxide → 1-[2-Fluoro-3-(methyloxy)-4-nitrophenyl]-4-(1-methylethyl)piperazine

Participants

Reaction Conditions

Reaction Steps

A pressure flask was charged with 1,2-difluoro-3-(methyloxy)-4-nitrobenzene (3.5 g, 18.5 mmol), dimethylsulfoxide (100 mL), isopropyl piperazine (5.41 mL, 22.2 mmol) and potassium carbonate (5.1 g, 37.04 mmol). The resulting slurry was warmed to 70° C. and stirred overnight. The next morning, the orange solution was poured into water and extracted with diethyl ether. The organic layer was dried over sodium sulfate, taken to a residue under reduced pressure, and purified via chromatography on SiO2 (0 to 10% MeOH/CH2CL2 with 0.2% NH3) to afford 1-[2-fluoro-3-(methyloxy)-4-nitrophenyl]-4-(1-methylethyl)piperazine as a yellow solid (5.7 g, quant. yield). 1H NMR (400 MHz, CDCl3) δ ppm 1.10 (d, J=6.60 Hz, 6 H), 2.71 (s, 4 H), 2.76 (s, 1 H), 3.29 (s, 4 H), 4.03 (s, 3 H), 6.64 (dd, J=9.53, 8.07 Hz, 1 H), 7.70 (dd, J=9.35, 2.02 Hz, 1 H).

Provenance & Evidence