Z-Asn-OtBu → L-Asparagine tert-butyl ester

HRID 1679835Notes

Reaction equation

HRID 1679835 reaction equation
[NH:1](C(OCC1C=CC=CC=1)=O)[C@H:2]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:3][C:4](=[O:6])[NH2:5]>C(OCC)(=O)C.[C].[Pd]>[NH2:1][C@H:2]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:3][C:4](=[O:6])[NH2:5]

Participants

4

Reactant 1

HCID 7015714Z-Asn-OtBu

Product 1

HCID 6995006L-Asparagine tert-butyl ester

Reagents, catalysts & solvents 2

HCID 178418390HCID 178418390, compoundCatalystHCID 8857Ethyl AcetateSolvent

Procedure

23.6 Grams (73.2 mmols) of Z-Asn-OtBu in 200 ml of ethyl acetate are hydrogenated in the presence of 2 g of palladium carbon (10% Pd) until, after 1 hour, hydrogen is no longer absorbed. The catalyst is filtered off and the filtrate concentrated, whereupon the product, melting at 96°-98° C., crystallizes out. Optical rotation [α]D20 =+2° (c=2.1 in methanol). In the thin-layer chromatogram on silica gel the Rf52 =0.30; Rf45 =0.50.

Workup

  1. customafter 1 hour
  2. customhydrogen is no longer absorbed
  3. filtrationThe catalyst is filtered off
  4. concentrationthe filtrate concentrated, whereupon the product, melting at 96°-98° C.
  5. customcrystallizes out
  6. customOptical rotation [α]D20 =+2° (c=2.1 in methanol)

Sources & evidence

ORD record
ord-f4f93f30d9f2472db0f1ff757226eea8
Source dataset
uspto-grants-1981_06
Patent number
US04271068

Reaction notes

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