1-(2-Bromophenyl)piperazine → 1-(2-Bromophenyl)-4-methylpiperazine

Participants

Reaction Steps

1-(2-Bromophenyl)piperazine (200 mg) was dissolved in formaldehyde (36.5% in water, 0.603 mL) and the solution was stirred 3 h at RT. NaBH3CN (78.2 mg) was added and the mixture was stirred at RT overnight. NaBH3CN (78.2 mg) was added again and the mixture was stirred at RT for 6 h. The solvents were removed in vacuo and the residue was taken up in EA, washed with sat. NaHCO3, dried (Na2SO4) and evaporated to dryness. The residue was purified by CC (Biotage, SNAP 25 g cartridge, solvent A: Hept; solvent B: EA; gradient in % B: 18 for 4CV, 18 to 100 over 10CV, 100 for 2CV, then MeOH flush for 4CV) to afford 1-(2-bromophenyl)-4-methylpiperazine (111 mg, colorless oil). LC-MS (B): tR=0.57 min; [M+H]+: 255.05.

Provenance & Evidence