Boron trifluoride etherate → tert-Butyl 6-{[(benzyloxy)carbonyl]amino}-2-bromohexanoate

HRID 2369218Notes

Reaction equation

HRID 2369218 reaction equation
[CH2:1]([O:8][C:9]([NH:11][CH2:12][CH2:13][CH2:14][CH2:15][C@H:16]([Br:20])[C:17]([OH:19])=[O:18])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.ClC(Cl)(Cl)C(=N)O[C:25]([CH3:28])([CH3:27])[CH3:26].B(F)(F)F.CCOCC.C(=O)(O)[O-].[Na+]>C(Cl)(Cl)Cl>[CH2:1]([O:8][C:9]([NH:11][CH2:12][CH2:13][CH2:14][CH2:15][CH:16]([Br:20])[C:17]([O:19][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:18])=[O:10])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

6

Reactant 4

HCID 8000Boron trifluoride etherateHCID 516892Sodium BicarbonateHCID 2734700Tert-butyl 2,2,2-trichloroethanimidateHCID 86762370(S)-6-{[(Benzyloxy)carbonyl]amino}-2-bromohexanoic acid2×

Product 1

HCID 71552828tert-Butyl 6-{[(benzyloxy)carbonyl]amino}-2-bromohexanoate

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent2×

Procedure

(S)-6-{[(Benzyl-oxy)carbonyl]amino}-2-bromohexanoic acid, 10.0 g (0.029 mole), was dissolved in chloroform, 20 mL. To this was added a solution of t-butyl trichloroacetimidate, 12.7 g (0.058 mole), dissolved in chloroform, 50 mL, drop-wise over 30 minutes. The mixture was allowed to stir an additional 5 minutes and boron trifluoride etherate, 100 μL, was added. The reaction mixture was allowed to stir overnight. Sodium bicarbonate, 5 g, was added. After stirring 10 minutes, hexanes, 50 mL, was added and the mixture filtered to remove the solids present. The filtrate was evaporated and the residue purified by flash chromatography, ethyl acetate-hexanes, to give a clear-colorless oil. The yield was 8.5 g, 73% based on starting (S)-6-{[(benzyloxy)carbonyl]amino}-2-bromohexanoic acid. NMR is consistent with structure.

Workup

  1. stirringto stir overnight
  2. stirringAfter stirring 10 minutes
  3. filtrationthe mixture filtered
  4. customto remove the solids present
  5. customThe filtrate was evaporated
  6. customthe residue purified by flash chromatography, ethyl acetate-hexanes
  7. customto give a clear-colorless oil

Sources & evidence

ORD record
ord-e9170a01f0824419b95febe4ace16437
Source dataset
uspto-grants-2014_04
Patent number
US08703937B2

Reaction notes

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