反应详情

温度

4 °C

A solution of N-Boc-(L)-Dopa (175 g, 0.59 mol) in methanol (1 L) was cautiously mixed with a methanolic solution of tetrabutylammonium hydroxide (1.0 M, 0.55 L) at 0° C. for 30 min. The mixture was then concentrated under reduced pressure and dried by azeotroping twice with toluene. The residue was crystallized after cooling at 4° C. for 16 h. The resulting crystalline solid was washed with acetone (400 mL×3), collected on a Buchner funnel, and then dried under high vacuum to afford 245 g (83% yield) of the title compound 1a. 1H NMR (400 MHz, DMSO-d6): δ 0.94 (t, J=7.6 Hz, 12H), 1.30 (m, 17H), 1.60 (m, 8H), 3.18 (m, 8H), 4.58 (m, 1H), 5.68 (d, J=5.6 Hz, 1H), 6.30 (d, J=7.6 Hz, 1H), 6.46 (d, J=8.0 Hz, 1H), 6.51 (s, 1H), 8.85 (s, 1H); 8.94 (s, 1H).

1. concentrationThe mixture was then concentrated under reduced pressure
2. customdried
3. customby azeotroping twice with toluene
4. customThe residue was crystallized
5. washThe resulting crystalline solid was washed with acetone (400 mL×3)
6. customcollected on a Buchner funnel
7. customdried under high vacuum