Triethylamine → (+)-(3,5-Dimethylbenzoyl)-3-(3,4-dichlorophenyl)piperazine

Participants

Reaction Steps

To a cooled solution of CH2Cl2 (600 mL) containing 2-(3,4-dichlorophenyl)piperazine (6.934 g, 30 mmol), 3,5-dimethylbenzoic acid (4.55 g, 30 mmol), and N-hydroxybenzotriazole monohydrate (4.05 g, 30 mmol) at -20° C. were added Et3N (4.2 mL, 30 mmol) and N,N-dimethylaminopropylethylcarbodimide (DEC) (5.86 g, 30 mmol) under nitrogen. The reaction was kept at -20° C. for an hour and gradually warmed to RT overnight. After stirring 22 hours, the reaction was complete and CH2Cl2 (200 mL) was added. The organic solution was washed with brine (150 mL, 3×), dried over MgSO4 , filtered and concentrated under vacuum to give 8.2 g of crude product. The product was crystallized from CH2Cl2 /Hexane to give a light yellow solid (6.3 g, 17.34 mmol, 57.8%), m.p.139°-141° C.; FAB MS [M+1]+ 35 Cl 363.1.

Provenance & Evidence