Carbon Dioxide → L-Proline 1,1-dimethylethyl ester

HRID 2071380Notes

Reaction equation

HRID 2071380 reaction equation
[C:1]([O:5][C:6](=[O:22])[C@@H:7]1[CH2:11][CH2:10][CH2:9][N:8]1C(OCC1C=CC=CC=1)=O)([CH3:4])([CH3:3])[CH3:2].C(=O)=O.[H][H]>C(O)C.[Pd]>[C:1]([O:5][C:6](=[O:22])[C@@H:7]1[CH2:11][CH2:10][CH2:9][NH:8]1)([CH3:4])([CH3:2])[CH3:3]

Participants

6

Reactant 3

HCID 280Carbon DioxideHCID 70197992-(1,1-Dimethylethyl) 1-(phenylmethyl) (2S)-1,2-pyrrolidinedicarboxylateHCID 178418361HCID 178418361, compound

Product 1

HCID 6453108L-Proline 1,1-dimethylethyl ester

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 702EthanolSolvent

Procedure

Benzyloxycarbonyl-L-proline tert.butyl ester (205 g.) is dissolved in absolute ethanol (1.2 l) and hydrogenated at normal pressure with 10% Pd on carbon (10 g.) until only a trace of carbon dioxide is observed in the hydrogen exit gas (24 hours). The catalyst is filtered off and the filtrate is concentrated in vacuo at 30 mm. Hg. The residue is distilled in vacuo, to obtain L-proline tert.butyl ester, b.p.1mm 50°-51°.

Workup

  1. filtrationThe catalyst is filtered off
  2. concentrationthe filtrate is concentrated in vacuo at 30 mm. Hg
  3. distillationThe residue is distilled in vacuo

Sources & evidence

ORD record
ord-ede5c4a46a964843b654ebdc06786bf1
Source dataset
uspto-grants-1977_09
Patent number
US04046889

Reaction notes

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