Benzyl chloroformate → (2S)-1-((benzyloxy)carbonyl)-4-hydroxypyrrolidine-2-carboxylic acid

HRID 1614352Notes

Reaction equation

HRID 1614352 reaction equation
[OH:1][CH:2]1[CH2:6][NH:5][C@H:4]([C:7]([OH:9])=[O:8])[CH2:3]1.C(=O)(O)[O-].[Na+].[CH2:15]([O:22][C:23](Cl)=[O:24])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1>O>[C:23]([N:5]1[CH2:6][CH:2]([OH:1])[CH2:3][C@H:4]1[C:7]([OH:9])=[O:8])([O:22][CH2:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1)=[O:24]

Participants

5

Reactant 3

HCID 10387Benzyl chloroformateHCID 69248L-Proline, 4-hydroxy-, cis-HCID 516892Sodium Bicarbonate

Product 1

HCID 12731799(2S)-1-((benzyloxy)carbonyl)-4-hydroxypyrrolidine-2-carboxylic acidYield 90%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To 20 g (152.5 mmol) of 4-hydroxy-L-proline in 35 ml of water was added 36.7 g (436.8 mmol) of sodium bicarbonate and the mixture was cooled to 10° C. before 32.5 g (190.5 mmol) of benzylchloroformate wa added dropwise. The cooling bath was then removed and the mixture was allowed to stir for 24 hours at room temperature. The pH of the reaction was then adjusted to 1 with concentrated HCl solution and the mixture was extracted with 3×100 ml portions of methylene chloride. The organic layers were dried over Na2SO4 and evaporated in vacuum to provide 36.4 g of the product as an oil (90% yield). NMR(CDCl3): 7.30 (m,5H, aromatic), 5.12 (m,2H), 4.50 (m,2H), 4.36 (m,2H), 3.6 (m,2H), 2.38 (m,2H).

Workup

  1. additionwa added dropwise
  2. customThe cooling bath was then removed
  3. extractionthe mixture was extracted with 3×100 ml portions of methylene chloride
  4. dry with materialThe organic layers were dried over Na2SO4
  5. customevaporated in vacuum

Sources & evidence

ORD record
ord-0e3f9058c7484bf998cd74b168bab273
Source dataset
uspto-grants-1993_03
Patent number
US05196548

Reaction notes

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