Glyoxal → 5,8-Dibromoquinoxaline

HRID 43047

Reaction equation

HRID 43047 reaction equation
[CH:1]([CH:3]=O)=O.[Br:5][C:6]1[CH:11]=[CH:10][C:9]([Br:12])=[C:8]([NH2:13])[C:7]=1[NH2:14]>CCO>[Br:5][C:6]1[CH:11]=[CH:10][C:9]([Br:12])=[C:8]2[C:7]=1[N:14]=[CH:1][CH:3]=[N:13]2

Participants

4

Reactant 2

HCID 7860GlyoxalHCID 118215323,6-Dibromobenzene-1,2-diamine

Product 1

HCID 115147635,8-DibromoquinoxalineYield 79.5%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A 40% aqueous solution of glyoxal (8.8 M, 6.3 mL, 55.1 mmol, 1.3 equiv) was added to a suspension of 3,6-dibromo-benzene-1,2-diamine (Step 1.6) (11.3 g, 42.4 mmol) in EtOH (280 mL). The reaction mixture was heated to reflux for 3 h and allowed to cool to rt overnight. Vacuum filtration of the reaction mixture afforded 9.7 g of the title compound as a yellow solid: APCI-MS: 286.2/288.1/290.1 [M−1]−; tR=4.40 min (System 1).

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureto reflux for 3 h
  3. filtrationVacuum filtration of the reaction mixture

Sources & evidence

ORD record
ord-3752f261596140a6bdbe69df656e39c9
Source dataset
uspto-grants-2013_09
Patent number
US08536175B2

Linked notes

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