Ethanol → Boc-D-alanine Ethyl Ester

HRID 1592366Notes

Reaction equation

HRID 1592366 reaction equation
[C:1]([NH:8][C@@H:9]([C:11]([OH:13])=[O:12])[CH3:10])([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].[CH2:14](O)[CH3:15].C1(N=C=NC2CCCCC2)CCCCC1>C(Cl)Cl.CN(C1C=CC=CN=1)C>[CH2:14]([O:12][C:11](=[O:13])[C@@H:9]([CH3:10])[NH:8][C:1]([O:3][C:4]([CH3:7])([CH3:5])[CH3:6])=[O:2])[CH3:15]

Participants

6

Reactant 3

HCID 702EthanolHCID 10868DicyclohexylcarbodiimideHCID 637606BOC-D-alanine

Product 1

HCID 12515028Boc-D-alanine Ethyl EsterYield 85.4%

Reagents, catalysts & solvents 2

HCID 218852-DimethylaminopyridineCatalystHCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

Boc-D-alanine (5.0 g, 26.4 mmol), dimethylaminopyridine (161 mg, 1.3 mMol), and ethanol (1.34 g, 29.1 mMol) were dissolved in methylene chloride (300 ml), and the solution was cooled to 0° C. To this solution was added 1,3-dicyclohexylcarbodiimide (6.0 g, 29.1 mMol). The mixture was allowed to slowly come to room temperature, and stirred under nitrogen overnight, during which time a white solid precipitated. The precipitate was removed by filtration, rinsed with methylene chloride, and the filtrate was concentrated to a pale yellow oil. Flash chromatography in 10-30% EtOAc/Hexanes yielded 4.9 g of a colorless oil as product. NMR (300 MHz, CDCl3) δ 5.05 (b, 1H), 4.28 (q, 1H, J=7 Hz), 4.20 (q, 2H, J=7 Hz), 1.45 (s, 9H), 1.38 (d, 3H, J=7 Hz), 1.28 (t, 3H, J=7 Hz).

Workup

  1. customto slowly come to room temperature
  2. customprecipitated
  3. customThe precipitate was removed by filtration
  4. washrinsed with methylene chloride
  5. concentrationthe filtrate was concentrated to a pale yellow oil

Sources & evidence

ORD record
ord-8cfbef61161c4f61aea8b240f554ed94
Source dataset
uspto-grants-2007_11
Patent number
US07291744B2

Reaction notes

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