Hydrochloric Acid → 1-tert-Butyl 2-methyl (2S,4R)-4-((methanesulfonyl)oxy)pyrrolidine-1,2-dicarboxylate

HRID 1941583Notes

Reaction equation

HRID 1941583 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:15][C@H:14]([OH:16])[CH2:13][C@H:9]1[C:10]([OH:12])=[O:11])=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH2:17](N(CC)CC)C.[CH3:24][S:25](Cl)(=[O:27])=[O:26].Cl>O1CCCC1.CO>[CH3:17][O:11][C:10]([C@@H:9]1[CH2:13][C@@H:14]([O:16][S:25]([CH3:24])(=[O:27])=[O:26])[CH2:15][N:8]1[C:6]([O:5][C:1]([CH3:4])([CH3:2])[CH3:3])=[O:7])=[O:12]

Participants

7

Procedure

To a solution of trans-1-t-butoxycarbonyl-4-hydroxy-L-proline (8.5 g) in tetrahydrofuran (110 ml) at -30° C., triethylamine (12.8 ml) and methanesulfonyl chloride (6.27 ml) are added. The mixture is stirred at the same temperature for 30 minutes. To the mixture triethylamine (5.13 ml) and methanol (30 ml) are added. The mixture is stirred for 30 minutes. The reaction mixture is acidified with 1N-hydrochloric acid (37 ml) and extracted with ethyl acetate. The extract is successively washed with water, aqueous sodium hydrogen carbonate, water and saturated brine, dried over sodium sulfate, and concentrated in vacuo. The residue is purified by silica gel column chromatography and recrystallized from toluene-petroleum ether to give (2S,4R)-1-t-butoxycarbonyl-4-methanesulfonyloxypyrrolidine-2-carboxylic acid methyl ester (9.16 g). Colorless crystals. Yield: 77%. mp. 86° to 87° C.

Workup

  1. stirringThe mixture is stirred for 30 minutes
  2. extractionextracted with ethyl acetate
  3. washThe extract is successively washed with water, aqueous sodium hydrogen carbonate, water and saturated brine
  4. dry with materialdried over sodium sulfate
  5. concentrationconcentrated in vacuo
  6. customThe residue is purified by silica gel column chromatography
  7. customrecrystallized from toluene-petroleum ether

Sources & evidence

ORD record
ord-da4e28947134418da70a371512a199d2
Source dataset
uspto-grants-1997_12
Patent number
US05703243

Reaction notes

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