1-Methyl-4-[1-(4-nitro-phenyl)-piperidin-3-ylmethyl]-piperazine was prepared by warming (4-Methyl-piperazin-1-yl)-[1-(4-nitro-phenyl)-piperidin-3-yl]-methanone of Example 443a with borane.THF (10 equivalents) at 60° C. for 16 hours, followed by a standard aqueous HCl workup. The resulting aqueous phase was neutralized with NaHCO3 and extracted with EtOAc (2×). The organics were combined, dried over Na2SO4, filtered, and concentrated under reduced pressure to give 1-Methyl-4-[1-(4-nitro-phenyl)-piperidin-4-ylmethyl]-piperazine as an orange oil, which was used for subsequent step without further manipulation. LC/MS (E/I+) 319.18 (M+H).
