4-Nitrophenol → Nalpha-t-butoxycarbonyl-D-valine p-nitrophenyl ester

HRID 1763737Notes

Reaction equation

HRID 1763737 reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([C:13]([OH:15])=[O:14])[CH:10]([CH3:12])[CH3:11])=[O:7])([CH3:4])([CH3:3])[CH3:2].C1(N=C=NC2CCCCC2)CCCCC1.[CH:31]1[C:36]([N+:37]([O-:39])=[O:38])=[CH:35][CH:34]=[C:33](O)[CH:32]=1>CN(C)C=O>[N+:37]([C:36]1[CH:31]=[CH:32][C:33]([O:14][C:13](=[O:15])[C@@H:9]([CH:10]([CH3:11])[CH3:12])[NH:8][C:6]([O:5][C:1]([CH3:3])([CH3:2])[CH3:4])=[O:7])=[CH:34][CH:35]=1)([O-:39])=[O:38]

Participants

5

Reactant 3

HCID 9804-NitrophenolHCID 10868DicyclohexylcarbodiimideHCID 637605(2R)-2-(((tert-butoxy)carbonyl)amino)-3-methylbutanoic acid

Product 1

HCID 22804944Nalpha-t-butoxycarbonyl-D-valine p-nitrophenyl ester

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Nα -t-Butoxycarbonyl-D-valine p-nitrophenyl ester is prepared from 5 g., 24 mmol, of Nα -t-butoxycarbonyl-D-valine, 4.8 g., 24 mmol, of dicyclohexylcarbodiimide and 3.4 g., 24 mmol, of p-nitrophenol dissolved in 25 ml. of dimethylformamide and the solution let stand at room temperature overnight. The solids are separated by filtration and the filtrate evaporated to dryness under reduced pressure. The residual oil is purified by chromatography on silica gel in methanol-benzene (5:95); 5 g.; [α]D23 +21° (c 1.0, methanol); ultraviolet in methanol λmax 270 E11 204.

Workup

  1. customat room temperature
  2. customovernight
  3. customThe solids are separated by filtration
  4. customthe filtrate evaporated to dryness under reduced pressure
  5. customThe residual oil is purified by chromatography on silica gel in methanol-benzene (5:95)

Sources & evidence

ORD record
ord-c24bcf4df8424f8a81620715d6c61d57
Source dataset
uspto-grants-1978_09
Patent number
US04111923

Reaction notes

Loading…