Chloroacetyl chloride → (S)-2-Chloro-N-(2,3-dihydroxypropyl)acetamide

Triethylamine (4.0 ml, 28.9 mmol) was added to a solution of (S)-3-amino-1,2-propanediol (2.2 g, 24.1 mmol) in a mixture of CH3CN/MeOH (80 mL/13 mL) at −10° C. under nitrogen. Chloroacetyl chloride (2.1 mL, 26.5 mmol) was then added dropwise at −10° C. over 30 min. The reaction mixture was allowed to reach room temperature and stirred for 16 h. The mixture was concentrated under vacuum and purified by flash column chromatography on silica gel, eluting with methanol/ethyl acetate (8/92), to give the title compound as a white solid (3.63 g, 90%).