Pyridine → 3-(s)-[(Benzyloxycarbonyl)amino]-2-(r,s)-acetoxy-4-methyl pentanoic acid

HRID 430941Notes

Reaction equation

HRID 430941 reaction equation
[CH2:1]([O:8][C:9]([NH:11][C@@H:12]([CH:18]([CH3:20])[CH3:19])[CH:13]([OH:17])[C:14]([OH:16])=[O:15])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.N1C=CC=CC=1.[C:27](OC(=O)C)(=[O:29])[CH3:28]>C(OCC)(=O)C>[CH2:1]([O:8][C:9]([NH:11][C@@H:12]([CH:18]([CH3:20])[CH3:19])[CH:13]([O:17][C:27](=[O:29])[CH3:28])[C:14]([OH:16])=[O:15])=[O:10])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

5

Reactant 3

HCID 1049PyridineHCID 7918Acetic AnhydrideHCID 131720810HCID 131720810, compound

Product 1

HCID 1317208113-(s)-[(Benzyloxycarbonyl)amino]-2-(r,s)-acetoxy-4-methyl pentanoic acidYield 80%

Reagents, catalysts & solvents 1

HCID 8857Ethyl AcetateSolvent

Procedure

To a solution of 3-(S)-[(benzyloxycarbonyl)amino]-2-(R,S)-hydroxy-4-methylpentanoic acid (1.70 g, 6.04 mmol) and pyridine (4.9 mL) was added acetic anhydride (5.7 mL, 6.17 g, 60.4 mmol) dropwise at room temperature. The reaction was allowed to stir overnight and was diluted with ethyl acetate and washed with water (2×). The organic layer was dried over magnesium sulfate, filtered and evaporated in vacuo to give a thick oil. The residue was purified by column chromatography on silica gel with 15% methanol/dichloromethane to afford 1.56 g (80%) of 3-(S)-[(benzyloxycarbonyl)amino]-2-(R,S)-acetoxy-4-methyl pentanoic acid as a light yellow viscous oil. FAB MS [M+H] m/z; Calcd: 324, Found: 324.

Workup

  1. washwashed with water (2×)
  2. dry with materialThe organic layer was dried over magnesium sulfate
  3. filtrationfiltered
  4. customevaporated in vacuo
  5. customto give a thick oil
  6. customThe residue was purified by column chromatography on silica gel with 15% methanol/dichloromethane

Sources & evidence

ORD record
ord-9532da9613a44d029086081c5dcf1349
Source dataset
uspto-grants-2003_12
Patent number
US06656910B2

Reaction notes

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