Hydrogen Bromide → 7-bromo-4-(bromoacetyl)-2H-chromen-2-one

HRID 741830

Reaction equation

HRID 741830 reaction equation
[Br:1][C:2]1[CH:11]=[C:10]2[C:5]([C:6]([C:13]([O:15]CC)=[CH2:14])=[CH:7][C:8](=[O:12])[O:9]2)=[CH:4][CH:3]=1.C1C(=O)N([Br:25])C(=O)C1.Br.OS([O-])=O.[Na+]>CC#N.O.C(OCC)(=O)C>[Br:1][C:2]1[CH:11]=[C:10]2[C:5]([C:6]([C:13](=[O:14])[CH2:15][Br:25])=[CH:7][C:8](=[O:12])[O:9]2)=[CH:4][CH:3]=1

Participants

7

Reactant 4

HCID 260Hydrogen BromideHCID 67184N-bromobutanimideHCID 233702047-bromo-4-(1-ethoxyvinyl)-2H-chromen-2-oneHCID 23665763Sodium Bisulfite

Product 1

HCID 233702397-bromo-4-(bromoacetyl)-2H-chromen-2-one

Reagents, catalysts & solvents 2

HCID 8857Ethyl AcetateSolventHCID 18373917Acetonitrile--water (1/1)Solvent

Procedure

To a solution of vinyl ether from Step 1 (1.02 g) in CH3CN:H2O 4:1 (25 mL) were successively added NBS (0.82 g) and concentrated HBr (20 μL). After being stirred at r.t. for 4 h, the reaction mixture was treated with 5% aqueous NaHSO3 (1 mL). Ethyl acetate was then added and the organic phase was washed with saturated aqueous NaHCO3, H2O and brine, dried (MgSO4) and evaporated. Flash chromatography of the residue (silica gel; hexane/EtOAc (85:15)) afforded the title compound as a white solid.

Workup

  1. washthe organic phase was washed with saturated aqueous NaHCO3, H2O and brine
  2. dry with materialdried (MgSO4)
  3. customevaporated

Sources & evidence

ORD record
ord-33c10a59f86a4b8dbee8b2a4e829a096
Source dataset
uspto-grants-1996_09
Patent number
US05552437

Linked notes

Loading…