Diethyl Oxalate → 5,7-Dichloro-1,4-dihydroquinoxaline-2,3-dione

HRID 54299

Reaction equation

HRID 54299 reaction equation
[C:1]([O:8]CC)(=O)[C:2]([O:4]CC)=O.[Cl:11][C:12]1[C:13]([NH2:20])=[C:14]([NH2:19])[CH:15]=[C:16]([Cl:18])[CH:17]=1>>[Cl:11][C:12]1[CH:17]=[C:16]([Cl:18])[CH:15]=[C:14]2[C:13]=1[NH:20][C:2](=[O:4])[C:1](=[O:8])[NH:19]2

Participants

3

Reactant 2

HCID 7268Diethyl OxalateHCID 42768353,5-Dichlorobenzene-1,2-diamine

Product 1

HCID 6502605,7-Dichloro-1,4-dihydroquinoxaline-2,3-dione

Procedure

The title compound (Leeson, P. D. et al., J. Med. Chem 34:1243 (1991)) was prepared using an adaptation of the method of Cheeseman. (Cheeseman, G. W. H. J. Chem. Soc. 1171 (1962)). A mixture of diethyl oxalate (4.12 g, 28.2 mmol) and 3,5-dichloro-1,2-diaminobenzene (500 mg, 2.82 mmol) was heated to reflux under N2 for 6 h. The reaction was allowed to cool to room temperature and the pale yellow shiny solid collected by vacuum filtration and rinsed with EtOH (20 mL) and air dried to give 286 mg (44%). mp 326°-328° C. (dec) Lit 337°-340° C.). 1H NMR (d6 -DMSO) δ7.05 (d, 1H, J=1.8, H-8), 7.32 (d, 1H, J=1.8, H-6), 11.5 (br s, 1H, NH), 12.1 (br s, 1H, NH). EIMS m/e 234 (M+4, 12), 232 (M+2, 67), 230 (M+, bp), 204 (52), 202 (77), 141 (19), 142 (59) EIHRMS calc. for C8H4Cl2N2O2 229.9650, found 229.9646.

Workup

  1. temperaturewas heated
  2. temperatureto reflux under N2 for 6 h
  3. filtrationthe pale yellow shiny solid collected by vacuum filtration
  4. washrinsed with EtOH (20 mL) and air
  5. customdried
  6. customto give 286 mg (44%)
  7. custommp 326°-328° C. (dec) Lit 337°-340° C.

Sources & evidence

ORD record
ord-f542b0f0d597415083dc46f85a3cb260
Source dataset
uspto-grants-1997_04
Patent number
US05622952

Linked notes

Loading…