Thionyl Chloride → 1-Methyl-4-{2-[(4-methylpiperazin-1-yl)methyl]-4-nitrophenyl}piperazine

To [2-(4-methylpiperazin-1-yl)-5-nitrophenyl]methanol (0.150 g, 0.60 mmol) in 5 mL of THF at 0° C. was added thionyl chloride (0.22 mL, 5 eq). The reaction mixture was refluxed for 45 minutes and then the solvent and the excess of thionyl chloride were evaporated. The residue was suspended in 5 mL of acetonitrile and 1-methylpiperazine (0.33 mL, 5 eq) was added at 0° C. The solution was stirred overnight at room temperature, evaporated and the residue was dissolved in ethyl acetate and washed with a saturated aqueous solution of Na2CO3. The aqueous layer was extracted with ethyl acetate and then the combined organic layers were dried over Na2SO4, filtered and evaporated. The residue was thoroughly washed with pentane and filtered off to yield expected compound as an orange powder (0.185 g, 92% yield).