Boc-L-Pro-Ome → 1-tert-Butyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxylate

HRID 350495

Reaction equation

HRID 350495 reaction equation
[CH3:1][O:2][C:3](=[O:16])[C@@H:4]1[CH2:8][CH2:7][CH2:6][N:5]1[C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10].C1C=C[NH+]=CC=1.C1C=C[NH+]=CC=1.[O-:29][Cr](O[Cr]([O-])(=O)=O)(=O)=O>C(Cl)Cl>[C:12]([O:11][C:9]([N:5]1[CH2:6][C:7](=[O:29])[CH2:8][CH:4]1[C:3]([O:2][CH3:1])=[O:16])=[O:10])([CH3:13])([CH3:15])[CH3:14]

Participants

4

Reactant 2

HCID 1277666Boc-L-Pro-OmeHCID 2724130Cornforth reagent

Product 1

HCID 42518531-tert-Butyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxylateYield 57%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a stirred solution of N-Boc proline methyl ester (2 .0 g, 8.15 mmol) in CH2Cl2 were added 3 A molecular sieves (2 g) and PDC (4.60 g, 12.2 mmol). The mixture was stirred for 3 days. The mixture was filtered through a Celiete pad and the filtrate was evaporated. The residue was chromatographed on silica gel with CHCl3-MeOH (10:1) as eluent to give methyl 1-(tert-butoxycarbonyl)-4-oxopyrrolidine-2-carboxylate (1.13 g, 57%) as a colorless oil. 1H-NMR (CDCl3) δ 1.46–1.48 (m, 9 H), 2.56–2.61 (m, 1 H), 2.88–3.00 (m, 1 H), 3.77 (s, 3 H), 3.82–3.88 (m, 2 H), 4.71–4.83 (m, 1 H).

Workup

  1. filtrationThe mixture was filtered through a Celiete pad
  2. customthe filtrate was evaporated
  3. customThe residue was chromatographed on silica gel with CHCl3-MeOH (10:1) as eluent

Sources & evidence

ORD record
ord-b091f12ac2424d2fb97894e4b4d9dd57
Source dataset
uspto-grants-2007_02
Patent number
US07179819B2

Linked notes

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