Benzil → 5,8-Dibromo-2,3-diphenylquinoxaline

HRID 1869569

Reaction equation

HRID 1869569 reaction equation
[Br:1][C:2]1[C:3]([NH2:10])=[C:4]([NH2:9])[C:5]([Br:8])=[CH:6][CH:7]=1.[C:11]1([C:17]([C:19]([C:21]2[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=2)=O)=O)[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.C([O-])(=O)C.[Na+]>C(O)(=O)C>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Br:8])=[C:4]2[C:3]=1[N:10]=[C:17]([C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)[C:19]([C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1)=[N:9]2

Participants

5

Reactant 3

HCID 8651BenzilHCID 517045Sodium AcetateHCID 118215323,6-Dibromobenzene-1,2-diamine

Product 1

HCID 224759015,8-Dibromo-2,3-diphenylquinoxaline

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

A solution of 5.3 g (20 mmol) of 3,6-dibromo-1,2-phenylenediamine 1,4 g (19 mmol) of benzil 2b, 4.2 g of sodium acetate and 150 ml of glacial acetic acid were refluxed for 4 hours. The precipitate was filtered off, washed with 100 ml of water and recrystallized twice from dioxane. Drying under reduced pressure at 50° C. gave the pure product in the form of colorless crystals, which according to HPLC had a purity of about 99.5%. The yield was 6.45 g (73%).

Workup

  1. filtrationThe precipitate was filtered off
  2. washwashed with 100 ml of water
  3. customrecrystallized twice from dioxane
  4. customDrying under reduced pressure at 50° C.
  5. customgave the pure product in the form of colorless crystals, which

Sources & evidence

ORD record
ord-ceb810b6b59945d5bc77f43ff667cf41
Source dataset
uspto-grants-2009_12
Patent number
US07638594B2

Linked notes

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