Triethylamine → 1-tert-Butyl 2-methyl (2S,4R)-4-((methanesulfonyl)oxy)pyrrolidine-1,2-dicarboxylate
Reaction equation
[CH3:1][O:2][C:3]([C@@H:5]1[CH2:9][C@@H:8]([OH:10])[CH2:7][N:6]1[C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])=[O:4].C(N(CC)CC)C.[CH3:25][S:26](Cl)(=[O:28])=[O:27]>C(Cl)Cl>[CH3:1][O:2][C:3]([C@@H:5]1[CH2:9][C@@H:8]([O:10][S:26]([CH3:25])(=[O:28])=[O:27])[CH2:7][N:6]1[C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])=[O:4]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
To a solution of (2S,4R)-4-hydroxy-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester (50 g, 0.2 mol), triethylamine (50.5 g, 0.5 mol) in DCM was added methanesulfonyl chloride (28 g, 0.25 mol) in portions and the reaction mixture was stirred at 0° C. for 20 min and at RT for 1.5 h, and washed with citric acid solution and water. The organic layer was dried over sodium sulfate and concentrated to give the title intermediate (70 g, 97% yield). 1H NMR (CDCl3, 400 MHz) δ (ppm) 5.23 (m, 1H), 4.44 (m, 1H), 3.75 (m, 5H), 3.04 (s, 3H), 2.64 (m, 1H), 2.26 (m, 1H), 1.43 (m, 9H).
Workup
- washwashed with citric acid solution and water
- dry with materialThe organic layer was dried over sodium sulfate
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-ffc8f07f95734b78aa422dabc804b978
- Source dataset
- uspto-grants-2015_12
- Patent number
- US09212168B2
Reaction notes
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