反応 #49157

反応方程式

N-Boc-L-proline

ethyl 3-(4-bromophenyl)-3-oxopropanoate

NBS

Hunig's base

Ethyl 2-bromo-3-(4-bromophenyl)-3-oxopropanoate

→

(2S)-2-(1-(4-bromophenyl)-3-ethoxy-1,3-dioxopropan-2-yl) 1-tert-butyl pyrrolidine-1,2-dicarboxylate

溶媒

acetonitrile

CH2Cl2

反応条件

後処理

1. 1
   洗浄The reaction mixture was washed with NaHCO3 solution, brine
2. 2
   乾燥dried (MgSO4)
3. 3
   ろ過filtered
4. 4
   濃縮concentrated
5. 5
   その他to give a residue which
6. 6
   その他was not purified
7. 7
   workup.STIRRINGthe solution stirred 18 hr
8. 8
   その他The solvent was removed by rotary evaporation
9. 9
   洗浄washed with 0.1 N HCl, and brine

実験手順

The ethyl 3-(4-bromophenyl)-3-oxopropanoate (15 g, 55 mmol) was dissolved in CH2Cl2 (600 mL) and freshly recrystallized NBS (9.8 g, 55 mmol) was added and the solution stirred 18 hr. The reaction mixture was washed with NaHCO3 solution, brine, and dried (MgSO4), filtered, and concentrated to give a residue which was not purified. Ethyl 2-bromo-3-(4-bromophenyl)-3-oxopropanoate (16.5 g, 48 mmol) and N-Boc-L-proline (10 g, 48 mmol) were taken up in acetonitrile (450 mL) and Hunig's base (16 mL, 95 mmol) was added and the solution stirred 18 hr. The solvent was removed by rotary evaporation and the residue taken up in ethyl acetate, washed with 0.1 N HCl, and brine. 1H NMR (300 MHz, DMSO-d6) δ 7.95 (d, J=8.4 Hz, 2H), 7.79 (d, J=8.4 Hz, 2H), 6.68-6.65 (m, 1H), 4.39-4.30 (m, 1H), 4.21-4.12 (m, 2H), 2.27-2.21 (m, 1H), 2.0-1.95 (m, 1H), 1.90-1.76 (m, 2H), 1.39 (s, 2H), 1.31 (s, 9H), 1.11 (t, J=7.3 Hz, 3H).

出典