(R)-3-aminobutanoic acid → (R)-3-((tert-butoxycarbonyl)amino)butanoic acid

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of (R)-3-aminobutanoic acid (2.415 g, 23.42 mmol) in dioxane (15 mL) and water (15.00 mL) was added TEA (4.90 mL, 35.1 mmol) dropwise. To the resulting light brown solution cooled at 0° C. was added portionwise di-tert-butyl carbonate (4.69 g, 26.9 mmol). The mixture was then stirred at rt for 16 hr. The reaction mixture was partitioned between water (80 mL) and EtOAc (80 mL). The separated aqueous layer was washed with EtOAc and acidified with 1 M aqueous KHSO4 to pH=3 and extracted with EtOAc (2×). The combined EtOAc extracts were washed with saturated aqueous NaCl (2×), dried over Na2SO4, filtered and concentrated to give (R)-3-(tert-butoxycarbonylamino)butanoic acid (4.301 g, 21.16 mmol, 90% yield) as a pale yellow solid. 1H NMR (400 MHz, CDCl3) δ ppm 4.92 (s, 1H), 4.14-3.96 (m, 2H), 2.56 (d, J=5.2 Hz, 2H), 1.45 (s, 9H), 1.25 (d, J=6.9 Hz, 3H).

Provenance & Evidence