Thionyl chloride (69.44 mmol, 5.06 mL, 5.0 eq.) was slowly added to a stirred solution of 2-morpholinoethan-1-ol (13.88 mmol, 2.5 g, 1.0 eq.) in dichloromethane (25 mL) with a catalytic amount of DMF at 0 °C. The reaction mixture was heated to 40 °C overnight. The reaction progress was monitored by TLC. After completion of the reaction, the solvent was removed by vacuum evaporation to give the crude product. The crude product was diluted with dichloromethane and washed with saturated sodium bicarbonate solution. The organic layer was concentrated under reduced pressure to give the crude residue. The crude product was purified by column chromatography using dichloromethane solution containing 3% methanol as eluent to afford the target compound 4-(2-chloroethyl)morpholine (2.0 g, 74.0% yield) as a colorless liquid.1H NMR (DMSO-d6, 300 MHz): δ 3.69 (t, J = 6.9 Hz, 2H), 3.57 (m, J = 4.5 Hz, 4H ), 2.64 (t, J = 6.9 Hz, 2H), 2.43 (t, J = 4.5 Hz, 4H); MS: [M + H]+ 149.95 (10%).
