Synthesis
(R)-3-Amino-3-phenylpropionic acid (2.1 g, 12.7 mmol, 1.0 equiv.) and NaHCO3 (1.6 g, 19 ) were dissolved in water (30 mL).
mmol, 1.5 equiv.) were dissolved in water (30 mL). Dioxane (30 mL) and [(CH3)3CO2C]2O (4.1 g, ) were dissolved in water (30 mL).
19 mmol, 1.5 equiv.) were added to the reaction mixture. The solution was stirred at room temperature for 8 hours. The solution was analyzed by TLC (SiO2, 50/25/25
The complete conversion of (R)-3-amino-3-phenylpropionic acid was confirmed by TLC (SiO2, 50/25/25 n-BuOH/HOAc/H2O). The solvent was removed by rotary evaporation. Distribute the crude mixture between HCl (1%) and EtOAc .
the crude mixture was partitioned between HCl (1%) and EtOAc . The aqueous layer was extracted with EtOAc. The combined organic extracts were dried with Na2SO4. The solvent was filtered and concentrated. The crude was purified by column chromatography, eluting with 10% , CH3OH/DCM, and then with 10% .
CH3OH/DCM to give (R)-Boc-beta-phenylalanine.
