Triethylamine → 4-(4-Chloro-2-methylbenzoyl)piperazin-2-one

Participants

Reaction Steps

2-piperazinone (0.701 g, 7 mmol, commercially available from e.g. Sigma-Aldrich) was dissolved in dichloromethane (DCM) (30 mL), and to this was added triethylamine (1.171 mL, 8.40 mmol). The solution was then cooled to 0° C. before 4-chloro-2-methylbenzoyl chloride (I55) (1.456 g, 7.70 mmol) in Dichloromethane (DCM) (5 mL) was added dropwise. The solution was stirred, under argon, for 30 minutes before the solvent was evaporated in vacuo. The remaining residue was then dissolved in DCM (40 mL) and the solution was washed with water (20 mL), a saturated solution of sodium bicarbonate (20 mL) and brine (20 mL). The organic phase was then dried over anhydrous sodium sulphate, and the solid sodium sulphate was then filtered off. The solvent was then evaporated in vacuo, and the remaining solid was stirred in hexane, at 55° C., for 30 minutes. The solid was then filtered off and the remaining solid was further purified by flash chromatography (Biotage SP4, 40S cartridge) with a gradient of 0-10% MeOH in DCM. TLC confirmed product location and the solvent from the combined fractions was evaporated in vacuo to yield the product in 0.798 g.

Provenance & Evidence