Morpholine → Ethyl alpha-oxo-4-morpholineacetate

A solution of ethyl 2-chloro-2-oxoacetate (1.25 g, 9.18 mmol) in diethyl ether (5 mL) was added dropwise to a solution of morpholine (1.0 g, 11.48 mmol) in diethyl ether (20 mL) and triethylamine (1.16 g, 11.48 mmol) at 0° C. The reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure. The yellow-colored oil was transferred into 25 mL iced water and extracted with ethyl acetate (3×20 mL). Combined organic layers were washed with brine, dried over anhydrous sodium sulphate, and concentrated under reduced pressure to give 1 g of the crude product, which was used further without any purification. Crude yield 47%. 1H NMR (400 MHz, CDCl3) δ 4.33-4.38 (q, 2H), 3.72-3.76 (m, 4H), 3.65-3.68 (m, 2H), 3.47-3.50 (m, 2H), 1.37-1.40 (t, 3H). LCMS m/z 187.93 [M+H]+, tR=0.525 min.