Oxalyl chloride → 3-Bromo-1-(4-fluorophenyl)piperazine 2,2-dimethylpropan-1-one

Participants

Reaction Steps

3-Bromo-2,2-dimethylpropionic acid (5.03 g, 27.8 mmol) was dissolved in DCM (60 mL). Oxalyl chloride (3.64 mL, 41.67 mmol) was added slowly over 10 minutes. The reaction mixture was stirred at room temperature for 18 hours and then concentrated in vacuo. The residue was dissolved in DCM (40 mL) and added to a solution of 4-fluorophenyl-piperazine (5.00 g, 27.8 mmol) and DIPEA (7.24 mL, 41.67 mmol) in DCM (30 mL) at 0° C. The reaction mixture was allowed to warm to room temperature over 1 hour and then stirred at room temperature for 16 hours. The reaction mixture was washed with 10% citric acid solution (2×100 mL), dried (MgSO4) and concentrated in vacuo to give 3-bromo-1-(4-fluorophenyl)piperazine-2,2-dimethylpropan-1-one (8.04 g, 84%) as a yellow solid which was used without further purification.

Provenance & Evidence