To a dry autoclave was added 63 g of (S)-2-(toluene-4-sulfonyloxy)-propionic acid and 500 mL of a 20% methanol solution of methylamine. The autoclave was sealed and the reaction was carried out at 15-30 °C until the starting material content was less than 5% by HPLC. Subsequently, the reaction mixture was transferred to a 50°C water bath with stirring. It was concentrated to dryness under reduced pressure, added 200 mL of water and concentrated again to about 200 mL. The product content was determined by GC analysis, resulting in 22.1 g of (R)-2-(methylamino)propanoic acid in 83.1% yield with an enantiomeric excess (ee) value of 97%.
