Sulfuric Acid → tert-butyl (2S)-2-amino-3-phenylpropanoate

Participants

Reaction Steps

98% H2SO4 (7 mL; 0.13 mol) was dropped in 20 min in dioxane (70 mL), keeping temperature of the solution below 20° C. After addition of L-phenylalanine (commercial product) (16.5 g; 0.10 mol), the solution was stirred for 12 h at 132 kPa under isobutene atmosphere (commercial product) (absorbed 45 g; 0.80 mol). The solution was dropped in a mixture of ice (200 g) and 10 N NaOH (30 mL, 0.30 mol) and extracted with Et2O (1 L). After washing with H2O (150 mL), the organic phase was dried over Na2SO4 and evaporated under vacuum The residue was distilled, to obtain the desired product (13 g; 0.059 mol). Yield 59%.

Provenance & Evidence