反应详情

N-tert-Butoxycarbonylalanine (2.8 g, 15 mmol) and carbonyldiimidazole (2.75 g, 17 mmol) are stirred together in 30 mL of dry THF under nitrogen for 1 h. To this is added 3 mL (30 mmol) of isobutyl amine, and the mixture is stirred for one week. It is then concentrated, dissolved in ethyl acetate, and washed successively with 1 N KHSO4, water, and brine, and dries over Na2SO4. Concentration affords the title compound as a white solid (2.25 g, 9.2 mmol, 62%). 1H NMR (CDCl3) δ 6.27 (m, 1H), 5.02 (m, 1H), 4.13 (m, 1H), 3.08 (m, 2H), 1.77 (m, 1H), 1.45 (s, 9H), 1.35 (d, J=7 Hz, 3H), 0.90 (d, J=7 Hz, 6H).

1. concentrationIt is then concentrated
2. dissolutiondissolved in ethyl acetate
3. washwashed successively with 1 N KHSO4, water, and brine, and dries over Na2SO4
4. concentrationConcentration