Cl[C:2]1[C:3]([CH3:20])=[C:4]([N:11]2[CH2:16][CH2:15][N:14]([CH:17]([CH3:19])[CH3:18])[CH2:13][CH2:12]2)[CH:5]=[CH:6][C:7]=1[N+:8]([O-:10])=[O:9].[CH3:21][O-:22].[Na+]>CN(C=O)C.O>[CH3:18][CH:17]([N:14]1[CH2:15][CH2:16][N:11]([C:4]2[CH:5]=[CH:6][C:7]([N+:8]([O-:10])=[O:9])=[C:2]([O:22][CH3:21])[C:3]=2[CH3:20])[CH2:12][CH2:13]1)[CH3:19]To a solution of 1-(3-chloro-2-methyl-4-nitrophenyl)-4-(1-methylethyl)piperazine (12.6 g, 42.4 mmol, 1 equiv) in 120 mL of DMF was added sodium methoxide (1.12 g, 21 mmol, 0.5 equiv) at 0° C. After stirring for 1 hour at room temperature, additional sodium methoxide was added (4.61 g, 85 mmol, 2 equiv, ×2) at 0° C. The mixture was warmed to 35° C. overnight. The next morning, the mixture was diluted with water, dried, and taken to a residue under reduced pressure. Recrystallization from ethyl acetate afforded 1-(1-methylethyl)-4-[2-methyl-3-(methyloxy)-4-nitrophenyl]piperazine (10.8 g, yield 87.1%) of sufficient purity for use in subsequent chemical transformations. 1H NMR (400 MHz, CDCl3) δ ppm 1.12 (d, J=6.53 Hz, 6H), 2.27 (s, 3H), 2.68-2.74 (m, 4H), 2.98-3.09 (m, 4H), 3.89 (s, 3H), 6.78 (d, J=9.2 Hz, 1H), 7.74 (d, J=9.2 Hz, 1H).
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