The general procedure for the synthesis of N-Boc-3-amino-2-hydroxypropionic acid from DL-isoserine (1 g, 9.52 mmol) and di-tert-butyl dicarbonate (2.7 g, 12.37 mmol) was as follows: DL-isoserine (1 g, 9.52 mmol) was dissolved in a solvent mixture of tert-butanol (40 mL) and 1 M aqueous NaOH (20 mL). Di-tert-butyl dicarbonate (2.7 g, 12.37 mmol) was added slowly under cooling in an ice bath. The reaction mixture was stirred at room temperature overnight. The progress of the reaction was monitored by thin layer chromatography (TLC) and after confirming the complete consumption of the raw material, the solvent was removed by concentration under reduced pressure in a water bath at 40 °C. Subsequently, three liquid-liquid extractions were performed with ethyl acetate and 1 M HCl, and the organic phases were combined and washed with saturated aqueous sodium chloride. The organic layer was dried over anhydrous magnesium sulfate and concentrated again under reduced pressure in a water bath at 40 °C to afford N-Boc-3-amino-2-hydroxypropionic acid (1.95 g, 100% yield). The product was characterized by 1H-NMR (500 MHz, CDCl3) with the following chemical shifts: δ 1.45 (9H, s), 3.51-3.65 (2H, m), 4.32 (1H, m), 5.10 (1H, br).
![Propanoic acid, 3-[[(1,1-dimethylethoxy)carbonyl]amino]-2-hydroxy- (9CI)](/CAS/GIF/218916-64-4.gif)