beta-D-Glucose pentaacetate → alpha-D-Glucopyranosyl bromide, tetraacetate

HRID 1404900Notes

Reaction equation

HRID 1404900 reaction equation
C(O[C@@H:5]1[O:22][C@H:21]([CH2:23][O:24][C:25](=[O:27])[CH3:26])[C@@H:16]([O:17][C:18](=[O:20])[CH3:19])[C@H:11]([O:12][C:13](=[O:15])[CH3:14])[C@H:6]1[O:7][C:8](=[O:10])[CH3:9])(=O)C.[BrH:28].CC(O)=O>C(Cl)(Cl)Cl>[CH3:26][C:25]([O:24][CH2:23][C@H:21]1[O:22][C@H:5]([Br:28])[C@H:6]([O:7][C:8]([CH3:9])=[O:10])[C@@H:11]([O:12][C:13]([CH3:14])=[O:15])[C@@H:16]1[O:17][C:18]([CH3:19])=[O:20])=[O:27]

Participants

4

Reactant 2

HCID 2724702beta-D-Glucose pentaacetateHCID 21893785Acetic Acid Mixture with Hydrobromic Acid

Product 1

HCID 101776alpha-D-Glucopyranosyl bromide, tetraacetateYield 85%

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

β-D-Glucose pentaacetate (2.5 g, 6.41 mmol) was added to HBr-AcOH (30%) with shaking. The reaction mixture was stirred at room temperature for 2 hours. The resultant reaction mixture was diluted with CHCl3 (50 mL), and the mixture was poured into ice water (15 mL). The chloroform layer was separated into an aqueous layer and a chloroform extraction layer (2×20 mL of CHCl3). The chloroform extraction layer was combined with the chloroform layer, and the mixture was then washed with water and dried over MgSO4, to thereby obtain acetobromo-α-D-glucose (4). The solvent was removed under reduced pressure, and the residue was recrystallized from a mixed solution of AcOEt and n-hexane, to thereby obtain a colorless needles 4 (2.23 g, 85%).

Workup

  1. stirringThe reaction mixture was stirred at room temperature for 2 hours
  2. customThe resultant reaction mixture
  3. customThe chloroform layer was separated into an aqueous layer
  4. extractiona chloroform extraction layer (2×20 mL of CHCl3)
  5. extractionThe chloroform extraction layer
  6. washthe mixture was then washed with water
  7. dry with materialdried over MgSO4
  8. customThe solvent was removed under reduced pressure
  9. customthe residue was recrystallized from a mixed solution of AcOEt and n-hexane

Sources & evidence

ORD record
ord-8f59ea8d38dc4995bf94d0318ae8ba5a
Source dataset
uspto-grants-2014_12
Patent number
US08916526B2

Reaction notes

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