Ammonia → Boc-(L)-Pal-NH2

HRID 963948Notes

Reaction equation

HRID 963948 reaction equation
[NH:1]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[C@H:2]([C:10](O)=[O:11])[CH2:3][C:4]1[CH:9]=[N:8][CH:7]=[CH:6][CH:5]=1.C([N:23](C(C)C)CC)(C)C.C(OC(Cl)=O)C(C)C.N>C(Cl)Cl.C(OCC)(=O)C>[NH:1]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[C@H:2]([C:10]([NH2:23])=[O:11])[CH2:3][C:4]1[CH:9]=[N:8][CH:7]=[CH:6][CH:5]=1

Participants

7

Reactant 4

HCID 222AmmoniaHCID 62365Isobutyl chloroformateHCID 81531DiisopropylethylamineHCID 7020919Boc-3-(3-pyridyl)-Ala-OH

Product 1

HCID 54368651Boc-(L)-Pal-NH2Yield 75%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolvent2×HCID 8857Ethyl AcetateSolvent

Conditions

Temperature
-15 °C

Procedure

Suspend Boc-(L)-Pal-OH (1.34 g, 5 mmol) in methylene chloride (50 mL) and cool to -15° C. Add diisopropylethylamine (963 μl, 5.5 mmol) and isobutylchloroformate (715 μL, 5.5 mmol). Stir the mixture 15 minutes at -15° C. Pass through the solution a vigorous stream of anhydrous ammonia (over solid sodium hydroxide) for about 3 minutes. Stir the mixture 10 minutes at -15° C. and 20 minutes at room temperature. Evaporate methylene chloride, add ethyl acetate (70 mL) and wash with saturated aqueous solution of sodium bicarbonate. Dry over magnesium sulfate and evaporate. Crystallize from ethyl acetate/hexane to give Boc-(L)-Pal-NH2 (0.98 g, 75%).

Workup

  1. stirringStir the mixture 10 minutes at -15° C.
  2. custom20 minutes
  3. customat room temperature
  4. washwash with saturated aqueous solution of sodium bicarbonate
  5. dry with materialDry over magnesium sulfate
  6. customevaporate
  7. customCrystallize from ethyl acetate/hexane

Sources & evidence

ORD record
ord-633d6029b33347babde579b18916fb75
Source dataset
uspto-grants-1998_06
Patent number
US05766932

Reaction notes

Loading…