Benzyl chloroformate → 4-[(R)-2-(tert-Butyldimethylsilyloxy)-1-(methyl)ethyl]pyrrolidine-1,3-dicarboxylic acid 1-benzyl ester 3-methyl ester

HRID 1917282Notes

Reaction equation

HRID 1917282 reaction equation
[CH2:1]([O:8][C:9](Cl)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:12][O:13][C:14]([CH:16]1[CH:20]([C@@H:21]([CH3:31])[CH2:22][O:23][Si:24]([C:27]([CH3:30])([CH3:29])[CH3:28])([CH3:26])[CH3:25])[CH2:19][N:18](CC2C=CC=CC=2)[CH2:17]1)=[O:15].O.C(=O)(O)[O-].[Na+]>ClCCl>[CH3:12][O:13][C:14]([CH:16]1[CH:20]([C@@H:21]([CH3:31])[CH2:22][O:23][Si:24]([C:27]([CH3:30])([CH3:29])[CH3:28])([CH3:25])[CH3:26])[CH2:19][N:18]([C:9]([O:8][CH2:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)=[O:10])[CH2:17]1)=[O:15]

Participants

5

Reactant 3

HCID 10387Benzyl chloroformateHCID 674907991-Benzyl-4-[(R)-2-(tert-butyldimethylsilyloxy)-1-(methyl)ethyl]pyrrolidine-3-carboxylic acid methyl esterHCID 86585896Sodium bicarbonate water

Product 1

HCID 674907934-[(R)-2-(tert-Butyldimethylsilyloxy)-1-(methyl)ethyl]pyrrolidine-1,3-dicarboxylic acid 1-benzyl ester 3-methyl esterYield 89.1%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

Benzyloxycarbonyl chloride (10.2 mL, 71.5 mmol) was added to a solution of 1-benzyl-4-[(R)-2-(tert-butyldimethylsilyloxy)-1-(methyl)ethyl]pyrrolidine-3-carboxylic acid methyl ester (14.0 g, 35.8 mmol) in dichloromethane (200 mL), and the mixture was stirred for one hour. Saturated sodium bicarbonate water was added to the reaction mixture. The organic layer was separated, dried over magnesium sulfate, and filtered. Then, the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1) to give 13.9 g (89%) of the diastereomer mixture title compound as a colorless oil. The diastereomers were used for the next step without separation.

Workup

  1. customThe organic layer was separated
  2. dry with materialdried over magnesium sulfate
  3. filtrationfiltered
  4. customThen, the solvent was evaporated under reduced pressure
  5. customThe residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1)

Sources & evidence

ORD record
ord-16defa7d78134104a146a7919a598ff4
Source dataset
uspto-grants-2013_12
Patent number
US08618094B2

Reaction notes

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