Dicyclohexylcarbodiimide → Boc-Asp(OBzl)-NHMe

HRID 963178Notes

Reaction equation

HRID 963178 reaction equation
[NH:1]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[C@H:2]([C:14](O)=[O:15])[CH2:3][C:4](=[O:13])[O:5][CH2:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1.[CH:24]1([N:30]=C=NC2CCCCC2)CCCCC1.OC1C2N=NNC=2C=CC=1.Cl.CN.C(N(C(C)C)CC)(C)C>O1CCCC1>[NH:1]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[C@H:2]([C:14]([NH:30][CH3:24])=[O:15])[CH2:3][C:4](=[O:13])[O:5][CH2:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1

Participants

7

Reactant 5

HCID 10868DicyclohexylcarbodiimideHCID 81531DiisopropylethylamineHCID 1581888N-tert-Butoxycarbonyl-L-aspartic acid beta-benzyl esterHCID 6364545Methylamine hydrochlorideHCID 178418300HCID 178418300, compound

Product 1

HCID 59516205Boc-Asp(OBzl)-NHMeYield 58.6%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Boc-Asp(OBzl) (6.4 g) was dissolved in tetrahydrofuran (30 ml), added with dicyclohexylcarbodiimide (4.1 g), hydroxybenzotriazole (3.0 g), methylamine hydrochloride (2.0 g) and diisopropylethylamine (3.9 g) under ice cooling and stirred for 10 hours. Insolubles were removed from the mixture by filtration and the filtrate was concentrated under reduced pressure. The residue was dissolved in ethyl acetate and the organic layer was washed with 10% aqueous solution of citric acid and saturated aqueous solution of sodium hydrogen carbonate and dried over anhydrous sodium sulfate. Then the ethyl acetate was evaporated under reduced pressure. The residue was recrystallized from ethyl acetate/hexane to give Boc-Asp(OBzl)-NHMe (3.9 g).

Workup

  1. customInsolubles were removed from the mixture by filtration
  2. concentrationthe filtrate was concentrated under reduced pressure
  3. dissolutionThe residue was dissolved in ethyl acetate
  4. washthe organic layer was washed with 10% aqueous solution of citric acid and saturated aqueous solution of sodium hydrogen carbonate
  5. dry with materialdried over anhydrous sodium sulfate
  6. customThen the ethyl acetate was evaporated under reduced pressure
  7. customThe residue was recrystallized from ethyl acetate/hexane

Sources & evidence

ORD record
ord-df6ae7d590dc4e59bae0eef0e6407b33
Source dataset
uspto-grants-1998_06
Patent number
US05763408

Reaction notes

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