Methyl chloroformate → (S)-Methyl 1-hydroxypropan-2-ylcarbamate

To a solution of (S)-alaninol (10 g, 130 mmol) and sodium bicarbonate (32.8 g, 390 mmol) in THF-H2O (1:1, 650 mL) at 0° C. was added dropwise methyl chloroformate (11.4 mL, 143 mmol). The mixture was stirred and allowed to warm to rt over 4 h, and was then extracted with ethyl acetate. The organic layer was washed with 1N aqueous sodium hydroxide solution and brine, and was then dried over sodium sulfate, filtered and concentrated to give the crude title compound, which was used without further purification. MS m/z 134.1 (M+1).