Hydrogen Bromide → Hydrogen Bromide

HRID 29737Notes

Reaction equation

HRID 29737 reaction equation
[BrH:1].[CH2:2]([O:9][C@H:10]1[C@H:16]([O:17][CH2:18][C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=2)[C@H:15]([O:25][CH2:26][C:27]2[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=2)[C@H:14]([CH3:33])[O:13][CH:11]1O)[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[N+](C1C=CC(C([O-])=O)=CC=1)([O-])=O>C(Cl)Cl>[BrH:1].[CH2:2]([O:9][C@H:10]1[C@H:16]([O:17][CH2:18][C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=2)[C@H:15]([O:25][CH2:26][C:27]2[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=2)[C@H:14]([CH3:33])[O:13][C@H:11]1[Br:1])[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1

Participants

5

Reactant 2

HCID 260Hydrogen BromideHCID 86592297HCID 86592297, compound2×

Product 2

HCID 260Hydrogen BromideHCID 10962107HCID 10962107, compound

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent3×

Conditions

Temperature
5 °C

Procedure

A saturated solution of HBr in CH2Cl2 (20.0 mL) was prepared by passing anhydrous HBr in CH2Cl2 at 0° C. for 30 min. This solution was added to a cold solution of the α-isomer of the 2,3,4-tri-O-benzylfucopyranose-p-nitrobenzoate (compound 8) (6.5 g, 11 mmol) in CH2Cl2 (150 mL) at 0-5° C., and the mixture was stirred at 5° C. for 30-40 min. The precipitated p-nitrobenzoic acid was filtered off, and the filtrate was successively washed with cold sat. NaHCO3 and water until neutral. The extract was dried (MgSO4) and the solvent removed at RT in vacuo to afford exclusively the α-fucopyranosyl bromide as a highly viscous liquid (5.3 g, yield 95%).

Workup

  1. customat 0° C.
  2. customfor 30 min
  3. filtrationThe precipitated p-nitrobenzoic acid was filtered off
  4. washthe filtrate was successively washed with cold sat. NaHCO3 and water until neutral
  5. dry with materialThe extract was dried (MgSO4)
  6. customthe solvent removed at RT in vacuo

Sources & evidence

ORD record
ord-d357768dab2f44999b2763c07e73d356
Source dataset
uspto-grants-2008_09
Patent number
US07422733B2

Reaction notes

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