Potassium Nitrate → 5-Bromo-6-nitro-7-fluoro-1,4-dihydro-2,3-quinoxalinedione

HRID 53745Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 53745
[Br:1][C:2]1[CH:11]=[C:10]([F:12])[CH:9]=[C:8]2[C:3]=1[NH:4][C:5](=[O:14])[C:6](=[O:13])[NH:7]2.[N+:15]([O-])([O-:17])=[O:16].[K+]>OS(O)(=O)=O>[Br:1][C:2]1[C:11]([N+:15]([O-:17])=[O:16])=[C:10]([F:12])[CH:9]=[C:8]2[C:3]=1[NH:4][C:5](=[O:14])[C:6](=[O:13])[NH:7]2

Komponenten

4

Reaktionsbedingungen

Temperatur
0 °C

Versuchsvorschrift

The method of Cheeseman, supra. was adapted. 5-Bromo-7-fluoro-1,4-dihydroquinoxaline-2,3-dione (77 mg, 0.30 mMol) was dissolved in concentrated H2SO4 (1 mL) at 0° C. for 30 min, and KNO3 (35 mg, 0.346 mMol, Baker) was added to this solution. The mixture was stirred at 0° C. for 3 h and then at room temperature for 30 h. The mixture was poured into ice water (10 g) and the precipitate was collected by filtration. The precipitate was dissolved in 1N NaOH (10 mL), then was acidified to pH=2 with 4N HCl to give cream precipitate, which was collected by filtration, and was dried in the air at 50° C. for 4 h affording pure (by NMR) 5-bromo-6-nitro-7-fluoro-1,4-dihydro-2,3-quinoxalinedione (81 mg, 90%), as a white amorphous solid; mp: 320°-25° C. (dec. from 290° C.). IR (KBr, cm-1): 3416, 3071, 2952, 1721, 1609, 1546. NMR (1H, DMSO-d6): δ 7.146 (d, J=10.2 Hz, 1H), 11.432 (s, 1H), 12.340 (s, 1H). HRMS: calcd. for C8H3N3O4BrF (M+) m/z: 302.9290, found: 302.9290.

Aufarbeitung

  1. waitat room temperature for 30 h
  2. filtrationthe precipitate was collected by filtration
  3. dissolutionThe precipitate was dissolved in 1N NaOH (10 mL)
  4. customto give cream precipitate, which
  5. filtrationwas collected by filtration
  6. customwas dried in the air at 50° C. for 4 h

Quellen und Nachweise

ORD-Eintrag
ord-0beecf167572474eb487113e086f6717
Quelldatensatz
uspto-grants-1997_04
Patentnummer
US05620979

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