2(1H)-Quinoxalinone → 6-Bromo-1,2-dihydroquinoxalin-2-one

HRID 1020732Notes

Reaction equation

HRID 1020732 reaction equation
[NH:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[N:4]=[CH:3][C:2]1=[O:11].[Br:12]Br>S(=O)(=O)(O)O.C(Cl)(Cl)(Cl)Cl.S([O-])([O-])(=O)=O.[Ag+2]>[Br:12][C:7]1[CH:6]=[C:5]2[C:10](=[CH:9][CH:8]=1)[NH:1][C:2](=[O:11])[CH:3]=[N:4]2

Participants

6

Reactant 2

HCID 145262(1H)-QuinoxalinoneHCID 24408Bromine

Product 1

HCID 126863946-Bromo-1,2-dihydroquinoxalin-2-oneYield 40%

Reagents, catalysts & solvents 3

HCID 178418844HCID 178418844, compoundCatalystHCID 1118Sulfuric AcidSolventHCID 5943Carbon TetrachlorideSolvent

Conditions

Temperature
50 °C

Procedure

The quinoxalin-2(1H)-one (14.6 g, 0.1 mol, Aldrich, cat. no. 260517) and silver sulphate (15.6 g, 0.05 mol) were dissolved in conc. Sulfuric acid (100 ml) at 20° C. Bromine (5.2 ml, 0.1 mol) was added and the reaction mixture was stirred vigorously for 24 hours. The reaction mass was then diluted with carbon tetrachloride (100 mL), and this was heated at 50° C. The reaction mass was then filtered and the filtrate was poured into ice cold water and stirred for 30 minutes to obtain a precipitate. The precipitate was filtered and the solid material was dried in vacuo to afford the title product (9.0 g, 40%).

Workup

  1. filtrationThe reaction mass was then filtered
  2. additionthe filtrate was poured into ice cold water
  3. stirringstirred for 30 minutes
  4. customto obtain a precipitate
  5. filtrationThe precipitate was filtered
  6. customthe solid material was dried in vacuo

Sources & evidence

ORD record
ord-aee6e2da2807442db7911757998664ff
Source dataset
uspto-grants-2014_05
Patent number
US08716473B2

Reaction notes

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