Oxalic acid dihydrate → 6,7-Dibromo-1,4-dihydroquinoxaline-2,3-dione

HRID 54326Notes

Reaction equation

HRID 54326 reaction equation
[Br:1][C:2]1[C:7]([Br:8])=[CH:6][C:5]([NH2:9])=[C:4]([NH2:10])[CH:3]=1.O.O.[C:13](O)(=[O:17])[C:14](O)=[O:15]>Cl>[Br:1][C:2]1[CH:3]=[C:4]2[C:5](=[CH:6][C:7]=1[Br:8])[NH:9][C:14](=[O:15])[C:13](=[O:17])[NH:10]2

Participants

4

Reactant 2

HCID 61373Oxalic acid dihydrateHCID 121969444,5-Dibromobenzene-1,2-diamine

Product 1

HCID 150218356,7-Dibromo-1,4-dihydroquinoxaline-2,3-dioneYield 92%

Reagents, catalysts & solvents 1

HCID 313Hydrochloric AcidSolvent

Conditions

Temperature
125 °C

Procedure

A mixture of 4,5-dibromo-1,2-phenylenediamine (1.862 g, 7.0 mmol) and oxalic acid dihydrate (1.06 g, 8.4 mmol) in 2N HCl (100 mL) was heated at 125° C. for 2 h then allowed to cool to 25° C. The solid was collected by vacuum filtration, washed with water and dried at 40° C. under 1 mmHg for 10 h affording 2.053 g (92%) of the title compound as a light brown powder. 1H NMR (DMSO-d6) 11.995 (s, 2H), 7.361 (s, 2H).

Workup

  1. temperatureto cool to 25° C
  2. filtrationThe solid was collected by vacuum filtration
  3. washwashed with water
  4. customdried at 40° C. under 1 mmHg for 10 h

Sources & evidence

ORD record
ord-6c3c3a404c6946c6be02ab29d466bc3c
Source dataset
uspto-grants-1997_04
Patent number
US05622952

Reaction notes

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