Oxalic Acid → 5,6,7-Trifluoro-1,4-dihydro-2,3-quinoxalinedione

HRID 1857375Notes

Reaction equation

HRID 1857375 reaction equation
[F:1][C:2]1[C:3]([NH2:11])=[C:4]([NH2:10])[CH:5]=[C:6]([F:9])[C:7]=1[F:8].[C:12](O)(=[O:16])[C:13](O)=[O:14]>Cl>[F:1][C:2]1[C:7]([F:8])=[C:6]([F:9])[CH:5]=[C:4]2[C:3]=1[NH:11][C:12](=[O:16])[C:13](=[O:14])[NH:10]2

Participants

4

Reactant 2

HCID 971Oxalic AcidHCID 27739583,4,5-Trifluorobenzene-1,2-diamine

Product 1

HCID 108463705,6,7-Trifluoro-1,4-dihydro-2,3-quinoxalinedioneYield 37%

Reagents, catalysts & solvents 1

HCID 313Hydrochloric AcidSolvent

Procedure

To a brown solution of 3,4,5-trifluoro-1,2-phenylenediamine (285 mg, 1.75 mmol) in aqueous 2N HCl (10 mL) is added oxalic acid (221 mg, 1,75 mmol). The brown mixture is brought to reflux and stirred under N2 overnight. The mixture is filtered to yield 139 mg (37%) of crude title compound. An analytical sample is prepared by dissolving 42 mg of this brown powder in 2.5 mL-boiling ethanol. Upon cooling, brown, rod-like, crystals are formed, which are filtered and dried in vacuo to-yield 15 mg (36%) of pure title compound: 1H NMR (DMSO-d6), 6.91 (m, 1H), 12.02 (s, 1H), 12.19 (s, 1H); analysis calculated for C8H3F3N2O2 : C, 44.46; H, 1.40; N, 12.96. Found: C, 44.42; H, 1.16; N, 12.76.

Workup

  1. temperatureto reflux
  2. filtrationThe mixture is filtered

Sources & evidence

ORD record
ord-081299d0d44e4731ac4301e56c87bcea
Source dataset
uspto-grants-2000_11
Patent number
US06147075

Reaction notes

Loading…