Synthese
To a solution of 4-chlorobutanoyl chloride (50.0 g, 355 mmol) and N-methoxy-N-methylamine hydrochloride (34.6 g, 355 mmol) in dichloromethane (DCM, 709 mL) was slowly added triethylamine (TEA, 109 mL, 780 mmol) at 0 °C, the addition process lasted 30 min. The reaction mixture was continued to be stirred at 0 °C for 3 hours. Upon completion of the reaction, it was quenched by the addition of water (250 mL). The organic layer was separated, washed with saturated brine, dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated under reduced pressure to afford 4-chloro-N-methoxy-N-methylbutyramide (55.0 g, 94% yield) as a yellow oil, which could be used for the subsequent reaction without further purification.1H-NMR (CDCl3, Varian, 400 MHz) δ: 2.12 ( 2H, quintuple peak, J = 6.4 Hz), 2.63 (2H, triple peak, J = 7.2 Hz), 3.19 (3H, single peak), 3.64 (2H, triple peak, J = 6.4 Hz), 3.71 (3H, single peak).
