3-Bromo-1-(4-fluorophenyl)piperazine-2,2-dimethylpropan-1-one (2.00 g, 5.83 mmol) was dissolved in N-methylpyrrolidinone (10 mL). N-Methylpiperazine (1.30 mL, 11.7 mmol) was added. The reaction mixture was split into four batches and each was heated at 200° C. for 15 minutes in a Biotage Initiator microwave at high absorption. The reaction mixtures were combined and dissolved in DCM (100 mL), and washed with water (2×80 mL), dried (MgSO4) and concentrated in vacuo. The resulting residue was purified by reverse phase column chromatography (gradient eluting with MeOH in water, with 1% formic acid in each solvent, 0-30%). The resulting residue was dissolved in DCM (100 mL) and stirred with solid Na2CO3 for 20 minutes, filtered and concentrated in vacuo, to give 1-[2,2-dimethyl-3-(4-methylpiperazin-1-yl)propanoyl]-4-(4-fluorophenyl)piperazine (451 mg, 21%) as a yellow oil.
