GENERAL STEPS: Example 2 Synthesis of (R)-1-amino-2-propanol. To a 500 mL reaction vessel was added L-threonine (10 g, 0.839 mol), 2-cyclohexen-1-one (8.07 g, 0.084 mol) and polyethylene glycol. The mixture was stirred under a nitrogen atmosphere at 150-160 °C. After 72 h, the reaction was judged complete when the crystals were completely dissolved and the mixture appeared homogeneous. The yield of (R)-1-amino-2-propanol was confirmed to be 80.6% by gas chromatographic analysis. Subsequently, the reaction solution was distilled under reduced pressure at the same temperature and the fractions were collected at 54-62 °C (1-20 hPa) to give (R)-1-amino-2-propanol (44.4 g, yield: 70.4%, chemical purity: 99.0%, optical purity: 99.9% ee).
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