Diisopropylethylamine → 3-Bromo-1-(4-chlorophenyl)piperazine 2,2-dimethylpropan-1-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3-Bromo-2,2-dimethylpropionic acid (1.50 g, 8.29 mmol) was dissolved in thionyl chloride (10 mL) and DMF (0.1 mL). The reaction mixture was heated at reflux for 1.5 hours and then concentrated in vacuo, The residue was dissolved in DCM (10 mL) and added to a solution of 4-chlorophenyl piperazine dihydrochloride (2.35 g, 8.70 mmol) and DIPEA (5.05 mL, 29.0 mmol) in DCM (20 mL) at 0° C. The reaction mixture was stirred at 0° C. for 2 hours and then concentrated in vacuo. The residue was dissolved in DCM (100 mL) and washed with 10% citric acid solution (50 mL), sat aq NaHCO3 solution (50 mL), brine (50 mL), dried (MgSO4) and concentrated in vacuo. The resulting residue was purified using normal phase column chromatography (eluting with heptane, followed by a 1:1 mixture of EtOAc:heptane) to give 3-bromo-1-(4-chlorophenyl)piperazine-2,2-dimethyl-propan-1-one (0.87 g, 29.3%) as a yellow solid.

Herkunft & Nachweise