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

HRID 2035373Notes

Reaction equation

HRID 2035373 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8](=[O:15])[CH2:9][C:10]([O:12][CH2:13][CH3:14])=[O:11])=[CH:4][CH:3]=1.C1C(=O)N(Br)C(=O)C1.BrC(C(C1C=CC(Br)=CC=1)=O)C(OCC)=O.[C:40]([N:47]1[CH2:54][CH2:53][CH2:52][C@H:48]1[C:49]([OH:51])=[O:50])([O:42][C:43]([CH3:46])([CH3:45])[CH3:44])=[O:41].CCN(C(C)C)C(C)C>C(Cl)Cl.C(#N)C>[N:47]1([C:40]([O:42][C:43]([CH3:46])([CH3:45])[CH3:44])=[O:41])[CH2:54][CH2:53][CH2:52][CH:48]1[C:49]([O:51][C@H:9]([C:10]([O:12][CH2:13][CH3:14])=[O:11])[C:8]([C:5]1[CH:4]=[CH:3][C:2]([Br:1])=[CH:7][CH:6]=1)=[O:15])=[O:50]

Participants

8

Procedure

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 rotorary 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).

Workup

  1. washThe reaction mixture was washed with NaHCO3 solution, brine
  2. dry with materialdried (MgSO4)
  3. filtrationfiltered
  4. concentrationconcentrated
  5. customto give a residue which
  6. customwas not purified
  7. stirringthe solution stirred 18 hr
  8. customThe solvent was removed by rotorary evaporation
  9. washwashed with 0.1 N HCl, and brine

Sources & evidence

ORD record
ord-178702bcd5484a1e8e90cd5eaa0c8ec2
Source dataset
uspto-grants-2013_11
Patent number
US08574563B2

Reaction notes

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